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Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

The Shape of Averaged Drop Size Distributions  

Science Conference Proceedings (OSTI)

The shape of averaged drop size distributions (DSD) is studied from a large sample of data (892 h) collected at several sites of various latitudes. The results show that neither the hypothesis of an exponential distribution to represent rainfall ...

Henri Sauvageot; Jean-Pierre Lacaux

1995-04-01T23:59:59.000Z

2

Statistical Tools for Drop Size Distributions: Moments and Generalized Gamma  

Science Conference Proceedings (OSTI)

Several problems associated with drop size distributions are treated. For rainfall rate R or radar reflectivity Z high powers of the drop diameters must be taken into account. This paper suggests methods to deal with the relevant moments and to ...

A. N. Aufder Maur

2001-02-01T23:59:59.000Z

3

The Development of Drop Size Distributions in Light Rain  

Science Conference Proceedings (OSTI)

A model of rain development based on the quasi-stochastic coalescence equation and including the sedimentation of drops has been used to study the formation of drop size distributions in conditions of weak updraft. Comparisons with “box model” ...

I. Zawadzki; E. Monteiro; F. Fabry

1994-04-01T23:59:59.000Z

4

Comparison of Polarimetric Radar Drop Size Distribution Retrieval Algorithms  

Science Conference Proceedings (OSTI)

Recently, two physically based algorithms, the “beta” (?) method and the “constrained-gamma” method, have been proposed for retrieving the governing parameters of the gamma drop size distribution (DSD) from polarimetric radar measurements. The ? ...

Edward A. Brandes; Guifu Zhang; J. Vivekanandan

2004-04-01T23:59:59.000Z

5

The Bias in Moment Estimators for Parameters of Drop Size Distribution Functions: Sampling from Exponential Distributions  

Science Conference Proceedings (OSTI)

The moment estimators frequently used to estimate parameters for drop size distribution (DSD) functions being “fitted” to observed raindrop size distributions are biased. Consequently, the fitted functions often do not represent well either the ...

Paul L. Smith; Donna V. Kliche

2005-08-01T23:59:59.000Z

6

Doppler Polarimetric Radar Measurements of the Gamma Drop Size Distribution of Rain  

Science Conference Proceedings (OSTI)

The conversion of radar reflections into rain intensities is dependent upon assumptions regarding the drop size distribution. The gamma drop size distribution contains three unknown parameters; the number of parameters that can be obtained ...

H. W. J. Russchenberg

1993-12-01T23:59:59.000Z

7

Examination of the ?–? Relation Suggested for Drop Size Distribution Parameters  

Science Conference Proceedings (OSTI)

Raindrop size distributions are often assumed to follow a three-parameter gamma distribution. Since rain intensity retrieval from radar observations is an underdetermined problem, there is great interest in finding physical correlations between ...

Dmitri N. Moisseev; V. Chandrasekar

2007-05-01T23:59:59.000Z

8

The Bias and Error in Moment Estimators for Parameters of Drop Size Distribution Functions: Sampling from Gamma Distributions  

Science Conference Proceedings (OSTI)

This paper complements an earlier one that demonstrated the bias in the method-of-moments (MM) estimators frequently used to estimate parameters for drop size distribution (DSD) functions being “fitted” to observed raindrop size distributions. ...

Paul L. Smith; Donna V. Kliche; Roger W. Johnson

2009-10-01T23:59:59.000Z

9

Intercomparison of Instruments used for Measurement of Cloud Drop Concentration and Size Distribution  

Science Conference Proceedings (OSTI)

Measurements of drop concentration and size distribution with the Clague droplet gun and the Forward Scattering Spectrometer Probe in 21 cumulus clouds on five days show no evidence of systematic differences between the two instruments. Though ...

S. C. Mossop

1983-03-01T23:59:59.000Z

10

A Probabilistic View on the Rain Drop Size Distribution Modeling: a Physical Interpretation of Rain Microphysics  

Science Conference Proceedings (OSTI)

The Rain Drop Size Distribution (RDSD) is defined as the relative frequency of raindrops per given diameter in a volume. This paper describes a mathematically-consistent modeling of the RDSD drawing on probability theory. It is shown that this ...

Francisco J. Tapiador; Ziad S. Haddad; Joe Turk

11

Functional Fits to Some Observed Drop Size Distributions and Parameterization of Rain  

Science Conference Proceedings (OSTI)

A data sample of optical spectrometer measurements that were obtained in two tropical cyclones is analyzed. The resultant drop size distributions are normalized and their shape is found to exhibit some curvature-departure from exponentiality. ...

Paul T. Willis

1984-05-01T23:59:59.000Z

12

Modeling the Variability of Drop Size Distributions in Space and Time  

Science Conference Proceedings (OSTI)

The information on the time variability of drop size distributions (DSDs) as seen by a disdrometer is used to illustrate the structure of uncertainty in radar estimates of precipitation. Based on this, a method to generate the space–time ...

Gyu Won Lee; Alan W. Seed; Isztar Zawadzki

2007-06-01T23:59:59.000Z

13

Analysis of Model-Produced Raindrop Size Distributions in the Small-Drop Range  

Science Conference Proceedings (OSTI)

Current models of drop coalescence and breakup generate raindrop size distributions that evolve toward an equilibrium whose form features a pronounced peak in the small-drop range. It has been known for some time that the peak can be attributed ...

Philip S. Brown Jr.

1999-05-01T23:59:59.000Z

14

The Effects of Drop Size Distribution Truncation on Rainfall Integral Parameters and Empirical Relations  

Science Conference Proceedings (OSTI)

A description is given of a method of estimating the effects of truncating the raindrop size distribution (DSD) at lower and upper drop diameters Dmin and Dmax which assumes that the DSD can be approximated by a gamma distribution (including the ...

Carlton W. Ulbrich

1985-06-01T23:59:59.000Z

15

Minimizing Instrumental Broadening of the Drop Size Distribution with the M-Fast-FSSP  

Science Conference Proceedings (OSTI)

A modified version of the Fast-FSSP (the so-called M-Fast-FSSP) is introduced. It allows minimization of the instrumental broadening of measured cloud drop size distributions caused by laser beam inhomogeneities. This is achieved by applying a ...

Sebastian Schmidt; Katrin Lehmann; Manfred Wendisch

2004-12-01T23:59:59.000Z

16

The Simultaneous Measurement of Rainfall Intensity, Drop-Size Distribution, and the Scattering of Visible Light  

Science Conference Proceedings (OSTI)

Field measurements were made of the attenuation of a low-power. He-Ne laser beam over a 272-m path. Concurrently, high-resolution (10 s) measurements of rainfall intensity were obtained at several points along the path and drop-size distributions ...

C. D. Stow; S. G. Bradley; K. Paulson; L. Couper

1991-10-01T23:59:59.000Z

17

The representation of rainfall drop-size distribution and kinetic energy Hydrology and Earth System Sciences, 8(5), 10011007 (2004) EGU  

E-Print Network (OSTI)

The representation of rainfall drop-size distribution and kinetic energy 1001 Hydrology and Earth-size distribution and kinetic energy Neil I. Fox Department of Soil, Environmental and Atmospheric Sciences373 Mc component of drop velocity. Keywords: drop-size distribution, drop kinetic energy, soil erosion Introduction

Paris-Sud XI, Université de

18

Drop Size Distributions Measured by a 2D Video Disdrometer: Comparison with Dual-Polarization Radar Data  

Science Conference Proceedings (OSTI)

An analysis of drop size distributions (DSDs) measured in four very different precipitation regimes is presented and is compared with polarimetric radar measurements. The DSDs are measured by a 2D video disdrometer, which is designed to measure ...

Terry J. Schuur; Alexander V. Ryzhkov; Dusan S. Zrni?; Michael Schönhuber

2001-06-01T23:59:59.000Z

19

Coincident In Situ and W-Band Radar Measurements of Drop Size Distribution in a Marine Stratus Cloud and Drizzle  

Science Conference Proceedings (OSTI)

Investigation of precipitation formation requires measurements of the drop size distribution in a cloud. These measurements have usually been made using ground-based radar systems or aircraft in situ probes. Difficulties encountered in practice ...

J. Galloway; A. Pazmany; J. Mead; R. E. McIntosh; D. Leon; J. French; S. Haimov; R. Kelly; G. Vali

1999-05-01T23:59:59.000Z

20

L-Moment Estimators as Applied to Gamma Drop Size Distributions  

Science Conference Proceedings (OSTI)

The traditional approach with experimental raindrop size data has been to use the method of moments in the fitting procedure to estimate the parameters for the raindrop size distribution function. However, the moment method is known to be biased ...

Donna V. Kliche; Paul L. Smith; Roger W. Johnson

2008-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Sensitivity of 5-cm Wavelength Polarimetric Radar Variables to Raindrop Axial Ratio and Drop Size Distribution  

Science Conference Proceedings (OSTI)

The sensitivity of polarimetric variables at a 5-cm wavelength to raindrop size and axial ratio is examined using T-matrix modeling of the scattering process for gamma raindrop size distributions fitted to tropical rainfall collected at Darwin, ...

T. D. Keenan; L. D. Carey; D. S. Zrni?; P. T. May

2001-03-01T23:59:59.000Z

22

On the Shape–Slope Relation of Drop Size Distributions in Convective Rain  

Science Conference Proceedings (OSTI)

The relation between the slope and shape parameters of the raindrop size distribution parameterized by a gamma distribution is examined. The comparison of results of a simple rain shaft model with an empirical relation based on disdrometer ...

Axel Seifert

2005-07-01T23:59:59.000Z

23

Optimal Determination of Parameters for Gamma-Type Drop Size Distributions Based on Moments  

Science Conference Proceedings (OSTI)

Measured raindrop size distributions are often approximated by analytical functions. The parameters determining such functions are usually derived from measured data. This procedure can suffer from various uncertainties. The most important of ...

Jan Handwerker; Winfried Straub

2011-04-01T23:59:59.000Z

24

Polarimetric Radar Rain Estimation through Retrieval of Drop Size Distribution Using a Bayesian Approach  

Science Conference Proceedings (OSTI)

This study proposes a Bayesian approach to retrieve raindrop size distributions (DSDs) and to estimate rainfall rates from radar reflectivity in horizontal polarization ZH and differential reflectivity ZDR. With this approach, the authors apply a ...

Qing Cao; Guifu Zhang; Edward A. Brandes; Terry J. Schuur

2010-05-01T23:59:59.000Z

25

Effects of Drop-Size-Distribution Truncation on Computer Simulations of Dual-Measurement Radar Methods  

Science Conference Proceedings (OSTI)

An investigation is made of the effects of truncating the raindrop-size distribution at minimum and maximum diameters on the results of computer simulations of dual-measurement radar methods. The dual-measurement methods investigated include ...

Carlton W. Ulbrich

1992-07-01T23:59:59.000Z

26

Characterization of Vertical Velocity and Drop Size Distribution Parameters in Widespread Precipitation at ARM Facilities  

Science Conference Proceedings (OSTI)

Extended, high-resolution measurements of vertical air motion and median volume drop diameter D0 in widespread precipitation from three diverse Atmospheric Radiation Measurement Program (ARM) locations [Lamont, Oklahoma, Southern Great Plains site ...

Scott E. Giangrande; Edward P. Luke; Pavlos Kollias

2012-02-01T23:59:59.000Z

27

Drop-size distribution for crosscurrent breakup of a liquid jet in a convective airstream  

E-Print Network (OSTI)

Experimental investigations have been completed in the study of a simulated fuel injector system implementing an airblast atomization process called a jet in a crossflow as the primary means of fuel atomization. To complete these studies an apparatus has been designed and constructed. A laser diffraction particle analyzer technique is used to spatially measure the spray Sauter-Mean Diameters. The Rosin-Rammler two parameter model is assumed for the droplet size distribution. Injection pressure for the injected liquid, distilled water, is held constant at 10.240 atm for the five different nozzle orifice diameters. A water rotameter is used to vary flowrates from 0.75 to 5.0 GPH and airflow Reynolds numbers are set at 50,000, 60,000, and 70,000 depending on the desired condition. SMD shows an increase in size for an increased distance from the top to the bottom of the test channel which is defined as the Y-Position from the orifice exit. The SMD growth rate decreases for increased water flowrates for a given airflow and orifice injector. For equal air-to-liquid ratios, overall SMD increases as the water flowrate and airflow Reynolds number combinations decrease. Overall SMD decreases for decreased air-to-liquid ratios. SMD decreases as the spray progresses downstream of the orifice exit in the direction of the airflow (X-Position) for a constant Y-Coordinate. A correlation of SMD-to-orifice diameter is determined to be as follows: [

Lyn, Gregory Michael

1994-01-01T23:59:59.000Z

28

An Analysis of Errors in Drop Size Distribution Retrievals and Rain Bulk Parameters with a UHF Wind Profiling Radar and a Two-Dimensional Video Disdrometer  

Science Conference Proceedings (OSTI)

Vertically pointed wind profiling radars can be used to obtain measurements of the underlying drop size distribution (DSD) for a rain event by means of the Doppler velocity spectrum. Precipitation parameters such as rainfall rate, radar ...

Laura Kanofsky; Phillip Chilson

2008-12-01T23:59:59.000Z

29

Doppler Cloud Radar Derived Drop Size Distributions in Liquid Water Stratus Clouds  

Science Conference Proceedings (OSTI)

A cloud particle size retrieval algorithm that uses radar reflectivity factor and Doppler velocity obtained by a 35-GHz Doppler radar and liquid water path estimated from microwave radiometer radiance measurements is developed to infer the size ...

Seiji Kato; Gerald G. Mace; Eugene E. Clothiaux; James C. Liljegren; Richard T. Austin

2001-10-01T23:59:59.000Z

30

First measurement of the small-scale spatial variability of the rain drop size distribution: Results from a crucial experiment and maximum entropy modeling  

E-Print Network (OSTI)

The main challenges of measuring precipitation are related to the spatio-temporal variability of the drop-size distribution, to the uncertainties that condition the modeling of that distribution, and to the instrumental errors present in the in situ estimations. This PhD dissertation proposes advances in all these questions. The relevance of the spatial variability of the drop-size distribution for remote sensing measurements and hydro-meteorology field studies is asserted by analyzing the measurement of a set of disdrometers deployed on a network of 5 squared kilometers. This study comprises the spatial variability of integral rainfall parameters, the ZR relationships, and the variations within the one moment scaling method. The modeling of the drop-size distribution is analyzed by applying the MaxEnt method and comparing it with the methods of moments and the maximum likelihood. The instrumental errors are analyzed with a compressive comparison of sampling and binning uncertainties that affect actual device...

Checa-Garcia, Ramiro

2013-01-01T23:59:59.000Z

31

Comparison of Drop Size Distribution Parameter (D0) and Rain Rate from S-Band Dual-Polarized Ground Radar, TRMM Precipitation Radar (PR), and Combined PR–TMI: Two Events from Kwajalein Atoll  

Science Conference Proceedings (OSTI)

The estimation of the drop size distribution parameter [median volume diameter (D0)] and rain rate (R) from the Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) as well as from combined PR–TRMM Microwave Imager (TMI) algorithms ...

V. N. Bringi; Gwo-Jong Huang; S. Joseph Munchak; Christian D. Kummerow; David A. Marks; David B. Wolff

2012-11-01T23:59:59.000Z

32

Characteristics of the Raindrop Size Distribution and Drop Shape Relation in Typhoon Systems in the Western Pacific from the 2D Video Disdrometer and NCU C-Band Polarimetric Radar  

Science Conference Proceedings (OSTI)

The drop size distribution (DSD) and drop shape relation (DSR) characteristics that were observed by a ground-based 2D video disdrometer and retrieved from a C-band polarimetric radar in the typhoon systems during landfall in the western Pacific, ...

Wei-Yu Chang; Tai-Chi Chen Wang; Pay-Liam Lin

2009-10-01T23:59:59.000Z

33

A new model of cloud drop distribution that simulates the observed drop  

NLE Websites -- All DOE Office Websites (Extended Search)

A new model of cloud drop distribution that simulates the observed drop A new model of cloud drop distribution that simulates the observed drop clustering: effect of clustering on extinction coefficient estimates Knyazikhin, Yuri Boston University Marshak, Alexander NASA Goddard Space Flight Center Larsen, Michael Michigan Technological University Wiscombe, Warren BNL/NASA Goddard Space Flight Center Category: Modeling Cloud droplet size distribution is one of the most fundamental subjects in cloud physics. Understanding of spatial distribution and small-scale fluctuations of cloud droplets is essential for both cloud physics and atmospheric radiation. For cloud physics, it relates to the coalescence growth of raindrops while for radiation, it has a strong impact on a cloud's radiative properties. We have developed new size dependent models

34

What is a Raindrop Size Distribution?  

Science Conference Proceedings (OSTI)

It is commonly understood that the number of drops that one happens to measure as a function of diameter in some sample represents the drop size distribution. However, recent observations show that rain is "patchy" suggesting that such a ...

A. R. Jameson; A. B. Kostinski

2001-06-01T23:59:59.000Z

35

Estimating the Accuracy of Polarimetric Radar–Based Retrievals of Drop-Size Distribution Parameters and Rain Rate: An Application of Error Variance Separation Using Radar-Derived Spatial Correlations  

Science Conference Proceedings (OSTI)

The accuracy of retrieving the two drop size distribution (DSD) parameters, median volume diameter (D0), and normalized intercept parameter (NW), as well as rain rate (R), from polarimetric C-band radar data obtained during a cool-season, long-...

M. Thurai; V. N. Bringi; L. D. Carey; P. Gatlin; E. Schultz; W. A. Petersen

2012-06-01T23:59:59.000Z

36

Use of an Ultrasonic Sodar to Sense Raindrop Size Distributions  

Science Conference Proceedings (OSTI)

The design of a sodar that uses ultrasound to remotely sense drop size distributions in rainfall is described. The Doppler shift is proportional to a drop's terminal velocity and gives a measure of the drop diameter, whereas the intensity of ...

Stuart Bradley; Tracey Webb

2002-08-01T23:59:59.000Z

37

Peaks in Raindrop Size Distributions  

Science Conference Proceedings (OSTI)

The multipeak behavior of raindrop size distributions has been studied. Peaks have been found for distinct drop diameters: 0.7, 1.0, 1.9, and possibly 3.2 mm. The probability is about 65% that at least one of these peaks exists in an observed ...

M. Steiner; A. Waldvogel

1987-10-01T23:59:59.000Z

38

Variational Optimization Method for Calculation of Cloud Drop Growth in an Eulerian Drop-Size Framework  

Science Conference Proceedings (OSTI)

A variational optimization (VO) method that requires specification of only one variable in each bin size for condensation and evaporation calculations in an Eulerian drop-size framework is proposed. The method is tested against the exact solution ...

Qingfu Liu; Yefim L. Kogan; Douglas K. Lilly; Marat P. Khairoutdinov

1997-10-01T23:59:59.000Z

39

ARM - Measurement - Hydrometeor Size Distribution  

NLE Websites -- All DOE Office Websites (Extended Search)

Size Distribution Size Distribution ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Hydrometeor Size Distribution The number of hydrometeors observed in a given size range. Categories Cloud Properties, Atmospheric State Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments LDIS : Laser Disdrometer Datastreams LDIS : Laser Disdrometer Datastreams PARS2 : OTT Parsivel2 Laser Disdrometer VDIS : Video Disdrometer Datastreams VDIS : Video Disdrometer Drop Size Distribution

40

A General Formulation for Raindrop Size Distribution  

Science Conference Proceedings (OSTI)

A general phenomenological formulation for drop size distribution (DSD), written down as a scaling law, is proposed. It accounts for all previous fitted DSDs. As a main implication of the expression proposed, the integral rainfall variables are ...

Daniel Sempere Torres; Josep M. Porrà; Jean-Dominique Creutin

1994-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Raindrop Size Distribution  

Science Conference Proceedings (OSTI)

This paper reviews some of the published results relating to raindrop-size distributions and couples this with some of the authors' results in order to show that the mathematical description of the distribution can be divided into three ...

M. C. Hodson

1986-07-01T23:59:59.000Z

42

Multimodal Raindrop Size Distributions  

Science Conference Proceedings (OSTI)

The raindrop size distributions (DSDs) observed over a short span usually have an erratic shape, with several relative maxima. This multimodal structure is studied from disdrometer data acquired in tropical and midlatitude areas. It is shown that ...

Henri Sauvageot; Manlandon Koffi

2000-08-01T23:59:59.000Z

43

An Evaluation of a Drop Distribution–Based Polarimetric Radar Rainfall Estimator  

Science Conference Proceedings (OSTI)

A method for estimating the governing parameters of gamma drop size distributions (DSDs) and associated rainfall rates from polarimetric radar measurements at the S band is examined. The technique uses radar reflectivity at horizontal ...

Edward A. Brandes; Guifu Zhang; J. Vivekanandan

2003-05-01T23:59:59.000Z

44

Laser capillary spectrophotometric acquisition of bivariate drop size and concentration data for liquid-liquid dispersion  

DOE Patents (OSTI)

A laser capillary spectrophotometric technique measures real time or near real time bivariate drop size and concentration distribution for a reactive liquid-liquid dispersion system. The dispersion is drawn into a precision-bore glass capillary and an appropriate light source is used to distinguish the aqueous phase from slugs of the organic phase at two points along the capillary whose separation is precisely known. The suction velocity is measured, as is the length of each slug from which the drop free diameter is calculated. For each drop, the absorptivity at a given wavelength is related to the molar concentration of a solute of interest, and the concentration of given drops of the organic phase is derived from pulse heights of the detected light. This technique permits on-line monitoring and control of liquid-liquid dispersion processes. 17 figures.

Tavlarides, L.L.; Bae, J.H.

1991-12-24T23:59:59.000Z

45

Modeling Raindrop Size Distribution and Z(R) Relations in the Western Mediterranean Area  

Science Conference Proceedings (OSTI)

This study shows the results of the modeling of drop size distributions (DSD) observed during a 2-yr study in Barcelona. Thirty-second individual sample collections of drop sizes and velocities were measured with an optical disdrometer and ...

Carlos Cerro; Bernat Codina; Joan Bech; Jeroni Lorente

1997-11-01T23:59:59.000Z

46

The Impression to Drop Size Ratio for the Raindrop Foil Impactor  

Science Conference Proceedings (OSTI)

A general calibration equation has been developed for the raindrop foil impactor. From experimental data the impression to drop size ratio is related to a nondimensional impact parameter and to the drop diameter to groove spacing ratio. These ...

R. L. Hobbs

1981-03-01T23:59:59.000Z

47

A Wind Tunnel Investigation of Interactions between Supercooled Precipitation-Size Water Drops  

Science Conference Proceedings (OSTI)

Laboratory experiments were performed to investigate interactions between small (400–900 ?m) precipitation-size drops at temperatures colder than 0°C. The investigation was accomplished by creating a light shower of supercooled drizzle drops in a ...

Robert R. Czys; Jeffrey K. Lew

1999-09-01T23:59:59.000Z

48

Exponential Size Distributions for Snow  

Science Conference Proceedings (OSTI)

Using airborne data from several recent field projects, the authors have taken another look at the properties of exponential ice particle size distributions (PSDs) when the PSDs are broad. Two primary questions are addressed: for what ranges of ...

Andrew J. Heymsfield; Paul Field; Aaron Bansemer

2008-12-01T23:59:59.000Z

49

Parameterizing the Raindrop Size Distribution  

Science Conference Proceedings (OSTI)

This paper addresses the problem of finding a parametric form for the raindrop size distribution (DSD) that 1) is an appropriate model for tropical rainfall, and 2) involves statistically independent parameters. Such a parameterization is derived ...

Ziad S. Haddad; Stephen L. Durden; Eastwood Im

1996-01-01T23:59:59.000Z

50

ARM - Measurement - Particle size distribution  

NLE Websites -- All DOE Office Websites (Extended Search)

size distribution size distribution ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Particle size distribution The number of particles present in any given volume of air within a specified size range. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments AOS : Aerosol Observing System CSPHOT : Cimel Sunphotometer TDMA : Tandem Differential Mobility Analyzer UHSAS : Ultra-High Sensitivity Aerosol Spectrometer Field Campaign Instruments

51

Study of a liquid-gas mixing layer: Shear instability and size of produced drops  

E-Print Network (OSTI)

Study of a liquid-gas mixing layer: Shear instability and size of produced drops Sylvain Marty +++++ Presented by £££££ Abstract We study experimentally the atomization of a liquid sheet by a parallel gas flow creation. We study in particular the regimes at low M (ratio of gas/liquid dynamic pressures), to test

Paris-Sud XI, Université de

52

The Drop-Size Response of the CSIRO Liquid Water Probe  

Science Conference Proceedings (OSTI)

The response of the CSIRO liquid water content (LWC) device to water drops of different sizes has been investigated in a wind tunnel. Two series of experiments were conducted. The first compared the probe-measured LWC of sprays with different ...

C. J. Biter; J. E. Dye; D. Huffman; W. D. King

1987-09-01T23:59:59.000Z

53

The Modification of Joint Size-Charge Distribution in Rain. Part II: Computations Involving Partial Coalescence  

Science Conference Proceedings (OSTI)

Raindrop collisional breakup is included in a model of joint size-charge distribution development. Consistent with experimental observations the model includes a finite filament (joining separating drops) that upon rupture produces charged ...

S. G. Bradley; C. D. Stow

1984-10-01T23:59:59.000Z

54

Wind-Induced Error of Raindrop Size Distribution Measurement Using a Two-Dimensional Video Disdrometer  

Science Conference Proceedings (OSTI)

The authors investigate a disdrometer that provides information on raindrop size distribution, terminal velocity, and shape using video imaging technology. Two video cameras are enclosed in a large box and provide images of the passing drops. The ...

Vladislav Nešpor; Witold F. Krajewski; Anton Kruger

2000-11-01T23:59:59.000Z

55

A Comparison of Techniques to Estimate Vertical Air Motions and Raindrop Size Distributions  

Science Conference Proceedings (OSTI)

Doppler velocity spectra collected at vertical incidence contain information on vertical air motions and drop-size distributions with high spatial and temporal resolution. In the past, the computational interdependence between vertical air ...

Karen L. Sangren; Peter S. Ray; Gene B. Walker

1984-06-01T23:59:59.000Z

56

Errors in Estimating Raindrop Size Distribution Parameters Employing Disdrometer and Simulated Raindrop Spectra  

Science Conference Proceedings (OSTI)

There have been debates and differences of opinion over the validity of using drop size distribution (DSD) models to characterize precipitation microphysics and to retrieve DSD parameters from multiparameter radar measurements. In this paper, ...

Qing Cao; Guifu Zhang

2009-02-01T23:59:59.000Z

57

An Investigation of the Slope–Shape Relation for Gamma Raindrop Size Distribution  

Science Conference Proceedings (OSTI)

The gamma drop size distribution (DSD) has been widely used in the meteorological community for years to model observed DSD. It has been found that the relation between the slope (?) and shape (?) parameters of the gamma DSD can be empirically ...

Yen-Hsyang Chu; Ching-Lun Su

2008-10-01T23:59:59.000Z

58

The Relationship between N0 and ? for Marshall-Palmer Type Raindrop-Size Distributions  

Science Conference Proceedings (OSTI)

For raindrop-size distributions of the form ND = N0e??D, where ND is the number of drops of diameter D per unit volume per unit increment in drop diameter, the parameters N0 and ? cannot be specified independently as functions of rainfall rate R. ...

J. A. Bennett; D. J. Fang; R. C. Boston

1984-05-01T23:59:59.000Z

59

Production mechanisms, number concentration, size distribution...  

NLE Websites -- All DOE Office Websites (Extended Search)

Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002asl2.441 Meeting Report Production mechanisms, number concentration, size distribution, chemical composition, and...

60

Gamma Size Distribution and Stochastic Sampling Errors  

Science Conference Proceedings (OSTI)

A maximum likelihood approach to the application of the gamma size distribution is described and compared with the method of moments approach suggested by Ulbrich. Estimation of distribution parameters based on the maximum likelihood principle ...

Raymond K. W. Wong; Norman Chidambaram

1985-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Gradually Truncated Log-normal distribution- Size distribution of firms  

E-Print Network (OSTI)

Many natural and economical phenomena are described through power law or log-normal distributions. In these cases, probability decreases very slowly with step size compared to normal distribution. Thus it is essential to cut-off these distributions for larger step size. Recently we introduce the gradually truncated power law distribution to successfully describe variation of financial, educational, physical and citation index. In the present work, we introduce gradually truncated log-normal distribution in which we gradually cut-off larger steps due to physical limitation of the system. We applied this distribution successfully to size distribution of USA´s manufactoring firms which is measured through their annual sell. The physical limitation are due to limited market size or shortage of highly competent executives. I.

Hari M. Gupta; José R. Campanha

2008-01-01T23:59:59.000Z

62

Particle size distribution instrument. Topical report 13  

DOE Green Energy (OSTI)

The development of an instrument to measure the concentration of particles in gas is described in this report. An in situ instrument was designed and constructed which sizes individual particles and counts the number of occurrences for several size classes. Although this instrument was designed to detect the size distribution of slag and seed particles generated at an experimental coal-fired magnetohydrodynamic power facility, it can be used as a nonintrusive diagnostic tool for other hostile industrial processes involving the formation and growth of particulates. Two of the techniques developed are extensions of the widely used crossed beam velocimeter, providing simultaneous measurement of the size distribution and velocity of articles.

Okhuysen, W.; Gassaway, J.D.

1995-04-01T23:59:59.000Z

63

Raindrop Size Distribution Measurements in Tropical Cyclones  

Science Conference Proceedings (OSTI)

Characteristics of the raindrop size distribution in seven tropical cyclones have been studied through impact-type disdrometer measurements at three different sites during the 2004–06 Atlantic hurricane seasons. One of the cyclones has been ...

Ali Tokay; Paul G. Bashor; Emad Habib; Takis Kasparis

2008-05-01T23:59:59.000Z

64

Acoustic Sounding of Raindrop Size Distribution  

Science Conference Proceedings (OSTI)

Radars have been successfully used for remote measurements of raindrop size distribution and rain intensity for many years. Over the last two decades, sodars have been increasingly applied to measure the parameters of precipitation. In the ...

Sergei V. Shamanaev

2003-01-01T23:59:59.000Z

65

Crushed Coal Particle Size Distribution Monitoring  

Science Conference Proceedings (OSTI)

This report summarizes an evaluation of different commercially available technologies for on-line monitoring of crushed coal size distribution with a subsequent laboratory test of the most promising system. The technology evaluation focused on image-based approaches for evaluating crushed coal size distribution that would address previous challenges encountered, including depth of field, image scale dependency upon the distance of the sample from the lens, image shadows caused by perimeter lighting, ...

2013-09-11T23:59:59.000Z

66

ARM - Measurement - Cloud particle size distribution  

NLE Websites -- All DOE Office Websites (Extended Search)

size distribution size distribution ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Cloud particle size distribution The number of cloud particles present in any given volume of air within a specified size range, including liquid and ice. Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments WSACR : Scanning ARM Cloud Radar, tuned to W-Band (95GHz) Field Campaign Instruments CPI : Cloud Particle Imager CLDAEROSMICRO : Cloud and Aerosol Microphysical Properties

67

ARM - Measurement - Aerosol particle size distribution  

NLE Websites -- All DOE Office Websites (Extended Search)

particle size distribution particle size distribution ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol particle size distribution The number of aerosol particles present in any given volume of air within a specificied size range Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments SMPS : Scanning mobility particle sizer TDMA : Tandem Differential Mobility Analyzer UHSAS : Ultra-High Sensitivity Aerosol Spectrometer Field Campaign Instruments

68

Measurements of Raindrop Size Distributions over the Pacific Warm Pool and Implications for Z–R Relations  

Science Conference Proceedings (OSTI)

Raindrop images obtained on research flights of the NCAR Electra aircraft in the Tropical Oceans Global Atmosphere Coupled Ocean–Atmosphere Response Experiment (TOGA COARE) are analyzed. The drop size distributions, based on the images obtained ...

Sandra E. Yuter; Robert A. Houze Jr.

1997-07-01T23:59:59.000Z

69

Numerical Investigation of Collision-Induced Breakup of Raindrops. Part II: Parameterizations of Coalescence Efficiencies and Fragment Size Distributions  

Science Conference Proceedings (OSTI)

Results of numerically investigated binary collisions of 32 drop pairs presented in Part I of this study are used to parameterize coalescence efficiencies and size distributions of breakup fragments of large raindrops.

Winfried Straub; Klaus Dieter Beheng; Axel Seifert; Jan Schlottke; Bernhard Weigand

2010-03-01T23:59:59.000Z

70

The Distribution of Cloud Horizontal Sizes  

Science Conference Proceedings (OSTI)

Cloud horizontal size distributions from near-global satellite data, from aircraft, and from a global high-resolution numerical weather prediction model, are presented for the scale range 0.1–8000 km and are shown to be well-represented using a ...

Robert Wood; Paul R. Field

2011-09-01T23:59:59.000Z

71

The Sampling Variations of Hailstone Size Distributions  

Science Conference Proceedings (OSTI)

The use of a shifted gamma size distribution for hailstone samples is proposed. This is shown to provide a better fit than the usual exponential form, using time-resolved Alberta data. It is also concluded that there is a dependence of the shape ...

Raymond K. W. Wong; Norman Chidambaram; Lawrence Cheng; Marianne English

1988-03-01T23:59:59.000Z

72

Lifetime of micrometer-sized drops of oil pressed by buoyancy against a planar interface  

E-Print Network (OSTI)

Emulsion Stability Simulations (ESS) are used to estimate the coalescence time of one drop of hexadecane pressed by buoyancy against a planar water/hexadecane interface. In the present simulations the homophase is represented by a big drop of oil at least 500 times larger than the approaching drop ($1\\,\\mu$m to $10\\,\\mu$m). Both deformable and non-deformable drops are considered along with six different diffusion tensors. In each case van der Waals, electrostatic, steric and buoyancy forces are taken into account. The coalescence times are estimated as the average of 1000 random walks. It is found that the repulsive potential barrier has a significant influence in the results. The experimental data can only be reproduced assuming negligible repulsive barriers, as well as non-deformable drops that move with a combination of Stokes and Taylor tensors as they approach the interface.

Clara Rojas; German Urbina-Villalba; Maximo Garcia-Sucre

2010-01-13T23:59:59.000Z

73

Evaluating Light Rain Drop Size Estimates from Multi-Wavelength Micropulse Lidar Network Profiling  

Science Conference Proceedings (OSTI)

We investigate multi-wavelength retrievals of median equivolumetric drop diameter, D0, suitable for drizzle and light rain, through collocated 355/527 nm Micro Pulse Lidar NETwork (MPLNET) observations collected during precipitation occurring 9 ...

Simone Lolli; Ellsworth J. Welton; James. R. Campbell

74

City Size Distributions For India and China  

E-Print Network (OSTI)

This paper studies the size distributions of urban agglomerations for India and China. We have estimated the scaling exponent for the Zipf's law with the Indian census data for the years of 1981-2001 and the Chinese census data for 1990 and 2000. Along with the biased linear fit estimate, the maximum likelihood estimate for the Pareto and Tsallis q-exponential distribution has been computed. For India, the scaling exponent is in the range of [1.88, 2.06] and for China, it is in the interval [1.82, 2.29]. The goodness-of-fit tests of the estimated distributions are performed using the Kolmogorov-Smirnov statistic.

Gangopadhyay, Kausik

2010-01-01T23:59:59.000Z

75

Statistics of voltage drop in radial distribution circuits: a dynamic programming approach  

E-Print Network (OSTI)

We analyze a power distribution line with high penetration of distributed generation and strong variations of power consumption and generation levels. In the presence of uncertainty the statistical description of the system is required to assess the risks of power outages. In order to find the probability of exceeding the constraints for voltage levels we introduce the probability distribution of maximal voltage drop and propose an algorithm for finding this distribution. The algorithm is based on the assumption of random but statistically independent distribution of loads on buses. Linear complexity in the number of buses is achieved through the dynamic programming technique. We illustrate the performance of the algorithm by analyzing a simple 4-bus system with high variations of load levels.

Turitsyn, Konstantin S

2010-01-01T23:59:59.000Z

76

Drop Shapes and Axis Ratio Distributions: Comparison between 2D Video Disdrometer and Wind-Tunnel Measurements  

Science Conference Proceedings (OSTI)

Comparisons of drop shapes between measurements made using 2D video disdrometer (2DVD) and wind-tunnel experiments are presented. Comparisons are made in terms of the mean drop shapes and the axis ratio distributions. Very close agreement of the ...

M. Thurai; V. N. Bringi; M. Szakáll; S. K. Mitra; K. V. Beard; S. Borrmann

2009-07-01T23:59:59.000Z

77

Determination of the Size and Concentration of Cloud Drops with an FSSP  

Science Conference Proceedings (OSTI)

A detailed size calibration of the Forward Scattering Spectrometer Probe (FSSP) over the size ranges of interest to cloud physics (2–47 ?m), is presented. The calibration includes laboratory tests with glass spheres, Mie scattering calculations ...

Todd A. Cerni

1983-08-01T23:59:59.000Z

78

Parameterizing Size Distribution in Ice Clouds  

SciTech Connect

PARAMETERIZING SIZE DISTRIBUTIONS IN ICE CLOUDS David L. Mitchell and Daniel H. DeSlover ABSTRACT An outstanding problem that contributes considerable uncertainty to Global Climate Model (GCM) predictions of future climate is the characterization of ice particle sizes in cirrus clouds. Recent parameterizations of ice cloud effective diameter differ by a factor of three, which, for overcast conditions, often translate to changes in outgoing longwave radiation (OLR) of 55 W m-2 or more. Much of this uncertainty in cirrus particle sizes is related to the problem of ice particle shattering during in situ sampling of the ice particle size distribution (PSD). Ice particles often shatter into many smaller ice fragments upon collision with the rim of the probe inlet tube. These small ice artifacts are counted as real ice crystals, resulting in anomalously high concentrations of small ice crystals (D < 100 µm) and underestimates of the mean and effective size of the PSD. Half of the cirrus cloud optical depth calculated from these in situ measurements can be due to this shattering phenomenon. Another challenge is the determination of ice and liquid water amounts in mixed phase clouds. Mixed phase clouds in the Arctic contain mostly liquid water, and the presence of ice is important for determining their lifecycle. Colder high clouds between -20 and -36 oC may also be mixed phase but in this case their condensate is mostly ice with low levels of liquid water. Rather than affecting their lifecycle, the presence of liquid dramatically affects the cloud optical properties, which affects cloud-climate feedback processes in GCMs. This project has made advancements in solving both of these problems. Regarding the first problem, PSD in ice clouds are uncertain due to the inability to reliably measure the concentrations of the smallest crystals (D < 100 µm), known as the “small mode”. Rather than using in situ probe measurements aboard aircraft, we employed a treatment of ice cloud optical properties formulated in terms of PSD parameters in combination with remote measurements of thermal radiances to characterize the small mode. This is possible since the absorption efficiency (Qabs) of small mode crystals is larger at 12 µm wavelength relative to 11 µm wavelength due to the process of wave resonance or photon tunneling more active at 12 µm. This makes the 12/11 µm absorption optical depth ratio (or equivalently the 12/11 µm Qabs ratio) a means for detecting the relative concentration of small ice particles in cirrus. Using this principle, this project tested and developed PSD schemes that can help characterize cirrus clouds at each of the three ARM sites: SGP, NSA and TWP. This was the main effort of this project. These PSD schemes and ice sedimentation velocities predicted from them have been used to test the new cirrus microphysics parameterization in the GCM known as the Community Climate Systems Model (CCSM) as part of an ongoing collaboration with NCAR. Regarding the second problem, we developed and did preliminary testing on a passive thermal method for retrieving the total water path (TWP) of Arctic mixed phase clouds where TWPs are often in the range of 20 to 130 g m-2 (difficult for microwave radiometers to accurately measure). We also developed a new radar method for retrieving the cloud ice water content (IWC), which can be vertically integrated to yield the ice water path (IWP). These techniques were combined to determine the IWP and liquid water path (LWP) in Arctic clouds, and hence the fraction of ice and liquid water. We have tested this approach using a case study from the ARM field campaign called M-PACE (Mixed-Phase Arctic Cloud Experiment). This research led to a new satellite remote sensing method that appears promising for detecting low levels of liquid water in high clouds typically between -20 and -36 oC. We hope to develop this method in future research.

DeSlover, Daniel; Mitchell, David L.

2009-09-25T23:59:59.000Z

79

Pore size distribution and accessible pore size distribution in bituminous coals  

Science Conference Proceedings (OSTI)

The porosity and pore size distribution of coals determine many of their properties, from gas release to their behavior on carbonization, and yet most methods of determining pore size distribution can only examine a restricted size range. Even then, only accessible pores can be investigated with these methods. Small-angle neutron scattering (SANS) and ultra small-angle neutron scattering (USANS) are increasingly used to characterize the size distribution of all of the pores non-destructively. Here we have used USANS/SANS to examine 24 well-characterized bituminous and subbituminous coals: three from the eastern US, two from Poland, one from New Zealand and the rest from the Sydney and Bowen Basins in Eastern Australia, and determined the relationships of the scattering intensity corresponding to different pore sizes with other coal properties. The range of pore radii examinable with these techniques is 2.5 nm to 7 {micro}m. We confirm that there is a wide range of pore sizes in coal. The pore size distribution was found to be strongly affected by both rank and type (expressed as either hydrogen or vitrinite content) in the size range 250 nm to 7 {micro}m and 5 to 10 nm, but weakly in intermediate regions. The results suggest that different mechanisms control coal porosity on different scales. Contrast-matching USANS and SANS were also used to determine the size distribution of the fraction of the pores in these coals that are inaccessible to deuterated methane, CD{sub 4}, at ambient temperature. In some coals most of the small ({approx} 10 nm) pores were found to be inaccessible to CD{sub 4} on the time scale of the measurement ({approx} 30 min - 16 h). This inaccessibility suggests that in these coals a considerable fraction of inherent methane may be trapped for extended periods of time, thus reducing the effectiveness of methane release from (or sorption by) these coals. Although the number of small pores was less in higher rank coals, the fraction of total pores that was inaccessible was not rank dependent. In the Australian coals, at the 10 nm to 50 nm size scales the pores in inertinites appeared to be completely accessible to CD{sub 4}, whereas the pores in the vitrinite were about 75% inaccessible. Unlike the results for total porosity that showed no regional effects on relationships between porosity and coal properties, clear regional differences in the relationships between fraction of closed porosity and coal properties were found. The 10 to 50 nm-sized pores of inertinites of the US and Polish coals examined appeared less accessible to methane than those of the inertinites of Australian coals. This difference in pore accessibility in inertinites may explain why empirical relationships between fluidity and coking properties developed using Carboniferous coals do not apply to Australian coals.

Sakurovs, Richard [ORNL; He, Lilin [ORNL; Melnichenko, Yuri B [ORNL; Radlinski, Andrzej Pawell [ORNL; Blach, Tomasz P [ORNL

2012-01-01T23:59:59.000Z

80

Drop Size Separation in Numerically Simulated Convective Clouds and Its Effect on Warm Rain Formation  

Science Conference Proceedings (OSTI)

It is shown that, as a result of the flow diffluence at the upper levels of the cloud, droplets of different sizes move along different trajectories. The small droplets with negligible fall velocities will have higher probability of being carried ...

Yefim L. Kogan

1993-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Particle Size Distribution Model for Leaching Kinetics of Alumina  

Science Conference Proceedings (OSTI)

Presentation Title, Particle Size Distribution Model for Leaching Kinetics of Alumina. Author(s), Li Bao, Ting-an Zhang, Weimin Long, Anh V Nguyen, Guozhi Lv, ...

82

Influence of Powder Particle Size Distribution and Pressure on the ...  

Science Conference Proceedings (OSTI)

during HIP were determined as a function of applied pressure, temperature and initial powder particle size distribution for the nickel base superalloy. RENE 95.

83

Measuring the Raindrop Size Distribution, ARM's Efforts at Darwin...  

NLE Websites -- All DOE Office Websites (Extended Search)

Measuring the Raindrop Size Distribution, ARM's Efforts at Darwin and SGP Bartholomew, Mary Jane Brookhaven National Laboratory Category: Instruments ARM has purchased two impact...

84

Evolution of droplet size distribution and autoconversion parameteriza...  

NLE Websites -- All DOE Office Websites (Extended Search)

Evolution of droplet size distribution and autoconversion parameterization in turbulent clouds McGraw, Robert Brookhaven National Laboratory Liu, Yangang Brookhaven National...

85

Size-independent vs. size-dependent policies in scheduling heavy-tailed distributions  

E-Print Network (OSTI)

We study the problem of scheduling jobs on a two-machine distributed server, where the job size distribution is heavy-tailed. We focus on two distributions, for which we prove that the performance of the optimal size-independent ...

Nham, John (John T.)

2008-01-01T23:59:59.000Z

86

Bounds on distance distributions in codes of known size  

Science Conference Proceedings (OSTI)

We treat the problem of bounding components of the possible distance distributions of codes given the knowledge of their size and possibly minimum distance. Using the Beckner inequality from harmonic analysis, we derive upper bounds on distance distribution ...

A. E. Ashikhmin; G. D. Cohen; M. Krivelevich; S. N. Litsyn

2005-01-01T23:59:59.000Z

87

Obtaining a bimodal grain size distribution via thermal means  

Science Conference Proceedings (OSTI)

Presentation Title, Obtaining a bimodal grain size distribution via thermal means ... manipulating thermal history, a family of bimodal grain size distributions may be formed. ... Mild Carbon Steel Quenche in Coconut Water, Fresh urine, Nigerian unadultrated up-wine, ... Multi-scale modeling of phase transformations in steels.

88

Productivity and Firm Size Distribution: Evidence from India's Organized and Unorganized Manufacturing Sectors  

E-Print Network (OSTI)

Size Distribution - Credit, Electricity, and Labor Reg-Change in Employment Size Distribution Electricity SurplusChange in Employment Size Distribution Electricity Surplus

Nataraj, Shanthi

2010-01-01T23:59:59.000Z

89

An Aggregate Model for the Particle Size Distribution in Saturn's Rings  

E-Print Network (OSTI)

Saturn's rings are known to consist of a large number of water ice particles. They form a flat disk, as the result of an interplay of angular momentum conservation and the steady loss of energy in dissipative particle collisions. For particles in the size range from a few centimeters to about a few meters a power law distribution of radii r^(-q), with q = 3, is implied by the light scattering properties of the rings. In contrast, for larger sizes the distribution drops steeply with increasing r. It has been suggested that this size distribution may arise from a balance between aggregation and fragmentation of ring particles, but to date neither the power-law dependence, nor the upper size-cutoff have been explained or quantified within a unique theory. Here we present a new kinetic model for the collisional evolution of the size distribution and show that the exponent q is expected to be constrained to the interval 2.75 < q < 3.5. An exponential cutoff towards larger particle sizes establishes naturally...

Brilliantov, Nikolai; Hayakawa, Hisao; Bodrova, Anna; Spahn, Frank; Schmidt, Juergen

2013-01-01T23:59:59.000Z

90

Optimal selection and sizing of distributed energy resources for distributed power systems  

Science Conference Proceedings (OSTI)

Optimal selection and sizing of distributed energy resources is an important research problem in the development of distributed power systems. This paper presents a methodology for optimal selection and sizing of distributed energy resources in integrated microgrids using the evolutionary strategy. Integrated microgrid is an innovative architecture in distributed power systems

Thillainathan Logenthiran; Dipti Srinivasan

2012-01-01T23:59:59.000Z

91

INITIAL PLANETESIMAL SIZES AND THE SIZE DISTRIBUTION OF SMALL KUIPER BELT OBJECTS  

SciTech Connect

The Kuiper Belt is a remnant from the early solar system and its size distribution contains many important constraints that can be used to test models of planet formation and collisional evolution. We show, by comparing observations with theoretical models, that the observed Kuiper Belt size distribution is well matched by coagulation models, which start with an initial planetesimal population with radii of about 1 km, and subsequent collisional evolution. We find that the observed size distribution above R {approx} 30 km is primordial, i.e., it has not been modified by collisional evolution over the age of the solar system, and that the size distribution below R {approx} 30 km has been modified by collisions and that its slope is well matched by collisional evolution models that use published strength laws. We investigate in detail the resulting size distribution of bodies ranging from 0.01 km to 30 km and find that its slope changes several times as a function of radius before approaching the expected value for an equilibrium collisional cascade of material strength dominated bodies for R {approx}< 0.1 km. Compared to a single power-law size distribution that would span the whole range from 0.01 km to 30 km, we find in general a strong deficit of bodies around R {approx} 10 km and a strong excess of bodies around 2 km in radius. This deficit and excess of bodies are caused by the planetesimal size distribution left over from the runaway growth phase, which left most of the initial mass in small planetesimals while only a small fraction of the total mass is converted into large protoplanets. This excess mass in small planetesimals leaves a permanent signature in the size distribution of small bodies that is not erased after 4.5 Gyr of collisional evolution. Observations of the small Kuiper Belt Object (KBO) size distribution can therefore test if large KBOs grew as a result of runaway growth and constrained the initial planetesimal sizes. We find that results from recent KBO occultation surveys and the observed KBO size distribution can be best matched by an initial planetesimal population that contained about equal mass per logarithmic mass bin in bodies ranging from 0.4 km to 4 km in radius. We further find that we cannot match the observed KBO size distribution if most of the planetesimal mass was contained in bodies that were 10 km in radius or larger simply because their resulting size distribution cannot be sufficiently depleted over 4.5 Gyr to match observations.

Schlichting, Hilke E. [UCLA, Department of Earth and Space Science, 595 Charles E. Young Drive East, Los Angeles, CA 90095 (United States); Fuentes, Cesar I.; Trilling, David E., E-mail: hilke@ucla.edu [Department of Physics and Astronomy, Northern Arizona University, P.O. Box 6010, Flagstaff, AZ 86011 (United States)

2013-08-01T23:59:59.000Z

92

Delayed Frost Growth on Jumping-Drop Superhydrophobic Surfaces  

Science Conference Proceedings (OSTI)

Self-propelled jumping drops are continuously removed from a condensing superhydrophobic surface to enable a micrometric steady-state drop size. Here, we report that subcooled condensate on a chilled superhydrophobic surface are able to repeatedly jump off the surface before heterogeneous ice nucleation occurs. Frost still forms on the superhydrophobic surface due to ice nucleation at neighboring edge defects, which eventually spreads over the entire surface via an inter-drop frost wave. The growth of this inter-drop frost front is shown to be up to three times slower on the superhydrophobic surface compared to a control hydrophobic surface, due to the jumping-drop effect dynamically minimizing the average drop size and surface coverage of the condensate. A simple scaling model is developed to relate the success and speed of inter-drop ice bridging to the drop size distribution. While other reports of condensation frosting on superhydrophobic surfaces have focused exclusively on liquid-solid ice nucleation for isolated drops, these findings reveal that the growth of frost is an inter-drop phenomenon that is strongly coupled to the wettability and drop size distribution of the surface. A jumping-drop superhydrophobic condenser was found to be superior to a conventional dropwise condenser in two respects: preventing heterogeneous ice nucleation by continuously removing subcooled condensate, and delaying frost growth by minimizing the success of interdrop ice bridge formation.

Boreyko, Jonathan B [ORNL; Collier, Pat [ORNL

2013-01-01T23:59:59.000Z

93

Cloud Droplet Size Distributions in Low-Level Stratiform Clouds  

Science Conference Proceedings (OSTI)

A database of stratus cloud droplet (diameter <50 ?m) size distribution parameters, derived from in situ data reported in the existing literature, was created, facilitating intercomparison among datasets and quantifying typical values and their ...

Natasha L. Miles; Johannes Verlinde; Eugene E. Clothiaux

2000-01-01T23:59:59.000Z

94

Raindrop Size Distributions and the Radar Bright Band  

Science Conference Proceedings (OSTI)

The relationship between raindrop size distribution, measured with a disdrometer, and a radar parameter of the melting-layer bright band is investigated. The data, obtained in July 1993 in Switzerland, cover 120 h of precipitation. A good ...

A. Huggel; W. Schmid; A. Waldvogel

1996-10-01T23:59:59.000Z

95

The Measurement of Bubble-Size Distributions by Acoustical Backscatter  

Science Conference Proceedings (OSTI)

A multifrequency acoustical-backscatter technique is described for determining the size distribution of bubbles with radii between 8 and 130 µm. The method makes use of the resonance in the microbubbles and operates at six frequencies ranging ...

Svein Vagle; David M. Farmer

1992-10-01T23:59:59.000Z

96

Hailstone Size Distributions and Their Relationship to Storm Thermodynamics  

Science Conference Proceedings (OSTI)

From ten storms, 184 time-resolved hailstone samples have been collected at the ground in Alberta. For each of the samples collected, hailstone size and concentration were determined and a truncated exponential distribution was fitted to the ...

L. Cheng; M. English; R. Wong

1985-10-01T23:59:59.000Z

97

Statistical Characteristics of Raindrop Size Distribution in Southwest Monsoon Season  

Science Conference Proceedings (OSTI)

Raindrop size distribution (DSD) parameters are retrieved from dual-frequency (UHF and VHF) wind profiler measurements made at Gadanki, India, in a summer monsoon season. The convoluted UHF spectra are first corrected for vertical air motion and ...

N. V. P. Kirankumar; T. Narayana Rao; B. Radhakrishna; D. Narayana Rao

2008-02-01T23:59:59.000Z

98

Measurement of Raindrop Size Distributions Using a Small Doppler Radar  

Science Conference Proceedings (OSTI)

A small X-band bistatic Doppler radar originally developed for use in automated weather stations as a Precipitation Occurrence Sensor System (POSS) can also measure real time raindrop size distributions. In contrast to large-scale pulsed Doppler ...

Brian E. Sheppard

1990-04-01T23:59:59.000Z

99

Some Factors Affecting the Size Distributions of Oceanic Bubbles  

Science Conference Proceedings (OSTI)

The effects of water temperature, dissolved gas saturation levels, and particulate concentrations on the size distribution of subsurface bubbles are investigated using numerical models. The input of bubbles, either at a constant rate in a “steady-...

S. A. Thorpe; P. Bowyer; D. K. Woolf

1992-04-01T23:59:59.000Z

100

Raindrop Size Distribution and Radar Parameters at Cape Verde  

Science Conference Proceedings (OSTI)

Precipitation measurement using passive or active microwaves from space- or ground-based radar involves hypotheses about the raindrop size distribution (DSD). A universal knowledge of DSD characteristics is needed. A 4-yr dataset collected with a ...

Armand Nzeukou; Henri Sauvageot; Abe Delfin Ochou; Cheikh Mouhamed Fadel Kebe

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Orientation Angle Distributions of Drops after an 80-m Fall Using a 2D Video Disdrometer  

Science Conference Proceedings (OSTI)

This note reports on the use of a 2D video disdrometer to estimate the orientation of drops (>2 mm) that were generated artificially and allowed to fall 80 m from a bridge with no obstruction and under calm conditions. This experimental setup ...

Gwo-Jong Huang; V. N. Bringi; M. Thurai

2008-09-01T23:59:59.000Z

102

Optimal Siting and Sizing of Distributed Energy Resources  

NLE Websites -- All DOE Office Websites (Extended Search)

Optimal Siting and Sizing of Distributed Energy Resources Optimal Siting and Sizing of Distributed Energy Resources Speaker(s): Johan Driesen Date: February 15, 2007 - 12:00pm Location: 90-3122 Seminar Host/Point of Contact: Chris Marnay Ongoing changes in the operation of distribution grids call for a new way to plan grid modifications. This presentation gives an overview of possible methods of long-term planning for the deployment of Distributed Energy Resources (distributed generation, storage and controllable loads) in a given grid. The placement and sizing of the units have to be considered, making this a complex optimization problem with discrete and continuous variables. In the optimization problem, multiple objectives are often conflicting, e.g. minimal grid losses, maximal use of the resources and voltage stability. An evolutionary algorithm (genetic algorithms) is used

103

Comparison of Raindrop Size Distribution Measurements by Collocated Disdrometers  

Science Conference Proceedings (OSTI)

An impact-type Joss–Waldvogel disdrometer (JWD), a two-dimensional video disdrometer (2DVD), and a laser optical OTT Particle Size and Velocity (PARSIVEL) disdrometer (PD) were used to measure the raindrop size distribution (DSD) over a 6-month ...

Ali Tokay; Walter A. Petersen; Patrick Gatlin; Matthew Wingo

2013-08-01T23:59:59.000Z

104

Methods to determine the size distribution of airborne rhinovirus  

NLE Websites -- All DOE Office Websites (Extended Search)

Methods to determine the size distribution of airborne rhinovirus Methods to determine the size distribution of airborne rhinovirus Title Methods to determine the size distribution of airborne rhinovirus Publication Type Report Year of Publication 2004 Authors Russell, Marion L., Regine Goth-Goldstein, Michael G. Apte, and William J. Fisk Publisher Lawrence Berkeley National Laboratory Abstract About 50% of viral-induced respiratory illnesses are caused by the human rhinovirus (HRV). Prior research has demonstrated that rhinovirus infections can be transmitted via person-to-person contact and via inhalation of infectious aerosols. Measurements of the concentrations and sizes of bioaerosols are critical for research on building characteristics, aerosol transport, and mitigation measures. To detect airborne HRV, we developed a quantitative reverse transcription-coupled polymerase chain reaction (RT-PCR) assay and verified that this assay detects HRV in nasal lavage samples. A quantitation standard was used to determine the assay detection limit of 5 fg of HRV RNA with a linear range over 10,000-fold. This assay was used to quantify the size distribution of an artificially-produced HRV aerosol captured with an Andersen six-stage cascade impactor. In future studies, we hope to use the methods developed here to characterize the size distribution of naturally occurring viral-aerosols

105

Method for measuring the size distribution of airborne rhinovirus  

NLE Websites -- All DOE Office Websites (Extended Search)

Method for measuring the size distribution of airborne rhinovirus Method for measuring the size distribution of airborne rhinovirus Title Method for measuring the size distribution of airborne rhinovirus Publication Type Conference Proceedings Year of Publication 2002 Authors Russell, Marion L., Regine Goth-Goldstein, Michael G. Apte, and William J. Fisk Conference Name Proceedings of the Indoor Air 2002 Conference, Monterey, CA Volume 1 Pagination 40-45 Publisher Indoor Air 2002, Santa Cruz, CA Abstract About 50% of viral-induced respiratory illnesses are caused by the human rhinovirus (HRV). Measurements of the concentrations and sizes of bioaerosols are critical for research on building characteristics, aerosol transport, and mitigation measures. We developed a quantitative reverse transcription-coupled polymerase chain reaction (RT-PCR) assay for HRV and verified that this assay detects HRV in nasal lavage samples. A quantitation standard was used to determine a detection limit of 5 fg of HRV RNA with a linear range over 1000-fold. To measure the size distribution of HRV aerosols, volunteers with a head cold spent two hours in a ventilated research chamber. Airborne particles from the chamber were collected using an Andersen Six-Stage Cascade Impactor. Each stage of the impactor was analyzed by quantitative RT-PCR for HRV. For the first two volunteers with confirmed HRV infection, but with mild symptoms, we were unable to detect HRV on any stage of the impactor

106

Rain Attenuation of Radar Echoes Considering Finite-Range Resolution and Using Drop Size Distributions  

Science Conference Proceedings (OSTI)

The classical rain attenuation correction scheme of Hitschfeld and Bordan (HIBO) and the newer iterative approach by Hildebrand (HL) are reconsidered. Although the motivation for the HL algorithm was an extension into ranges, where HIBO tends to ...

Gerhard Peters; Bernd Fischer; Marco Clemens

2010-05-01T23:59:59.000Z

107

Drop-Size Distributions in Thunderstorms Measured by Optical Disdrometers during VORTEX2  

Science Conference Proceedings (OSTI)

When studying the influence of microphysics on the near-surface buoyancy tendency in convective thunderstorms, in situ measurements of microphysics near the surface are essential and those are currently not provided by most weather radars. In this ...

Katja Friedrich; Evan A. Kalina; Forrest J. Masters; Carlos R. Lopez

2013-04-01T23:59:59.000Z

108

Nucleation Scavenging of Smoke Particles and Simulated Drop Size Distributions over Large Biomass Fires  

Science Conference Proceedings (OSTI)

A prescribed burn experiment was conducted in Hardiman Township, Ontario, Canada in August 1987. The fire was of adequate intensity to force the formation of a cumulus cloud, and much of the smoke passed through this cloud. The smoke plume and ...

Catherine C. Chuang; Yoyce E. Penner; Leslie L. Edwards

1992-07-01T23:59:59.000Z

109

Acoustical Rainfall Analysis: Rainfall Drop Size Distribution Using the Underwater Sound Field  

Science Conference Proceedings (OSTI)

Rainfall estimation is difficult, especially in oceanic regions where land-based techniques are unavailable. Fortunately, rain produces a loud and unique sound underwater that can be used to detect and quantify rainfall. Laboratory studies of the ...

Jeffrey A. Nystuen

1996-02-01T23:59:59.000Z

110

Free energy and size distributions of micelles in solution  

Science Conference Proceedings (OSTI)

This paper presents a new derivation of the free energy of micellar solutions. From this free energy a micelle size distribution can be calculated. By using a density functional model for the bulk contribution to the free energy and a simple approximation for the micelle (proper) contribution

P. S. Christopher; David W. Oxtoby

2003-01-01T23:59:59.000Z

111

Aerosol Size Distributions from Genetic Inversion of Polar Nephelometer Data  

Science Conference Proceedings (OSTI)

It is shown that genetic inversions can be used to recover lognormal aerosol size distributions from multiangle optical scattering cross-section data measured by a polar nephelometer at a wavelength of 0.532 ?m. The inversions can also be used to ...

B. R. Lienert; J. N. Porter; S. K. Sharma

2003-10-01T23:59:59.000Z

112

Particle-Size-Distribution of Nevada Test Site Soils  

SciTech Connect

The amount of each size particle in a given soil is called the particle-size distribution (PSD), and the way it feels to the touch is called the soil texture. Sand, silt, and clay are the three particle sizes of mineral material found in soils. Sand is the largest sized particle and it feels gritty; silt is medium sized and it feels floury; and clay is the smallest and if feels sticky. Knowing the particle-size distribution of a soil sample helps to understand many soil properties such as how much water, heat, and nutrients the soil will hold, how fast water and heat will move through the soil, and what kind of structure, bulk density and consistence the soil will have. Furthermore, the native particle-size distribution of the soil in the vicinity of ground zero of a nuclear detonation plays a major role in nuclear fallout. For soils that have a high-sand content, the near-range fallout will be relatively high and the far-range fallout will be relatively light. Whereas, for soils that have a high-silt and high-clay content, the near-range fallout will be significantly lower and the far-range fallout will be significantly higher. As part of a program funded by the Defense Threat Reduction Agency (DTRA), the Lawrence Livermore National Laboratory (LLNL) has recently measured the PSDs from the various major areas at the Nevada Test Site where atmospheric detonations and/or nuclear weapon safety tests were performed back in the 50s and 60s. The purpose of this report is to document those results.

Spriggs, G; Ray-Maitra, A

2007-09-17T23:59:59.000Z

113

Influence of Particle Size Distribution on Random Close Packing  

E-Print Network (OSTI)

The densest amorphous packing of rigid particles is known as random close packing. It has long been appreciated that higher densities are achieved by using collections of particles with a variety of sizes. The variety of sizes is often quantified by the polydispersity of the particle size distribution: the standard deviation of the radius divided by the mean radius. Several prior studies quantified the increase of the packing density as a function of polydispersity. Of course, a particle size distribution is also characterized by its skewness, kurtosis, and higher moments, but the influence of these parameters has not been carefully quantified before. In this work, we numerically generate many packings with different particle radii distributions, varying polydispersity and skewness independently of one another. We find two significant results. First, the skewness can have a significant effect on the packing density and in some cases can have a larger effect than polydispersity. Second, the packing fraction is relatively insensitive to the value of the kurtosis. We present a simple empirical formula for the value of the random close packing density as a function of polydispersity and skewness.

Kenneth W. Desmond; Eric R. Weeks

2013-03-19T23:59:59.000Z

114

Time Evolution of the Mutual Fund Size Distribution  

E-Print Network (OSTI)

We investigate the process of mutual fund growth both empirically and theoretically. The size of large mutual funds has a heavy tailed distribution that has been conjectured to be a power law; we investigate the data more carefully and show that it is better described by a log normal. To explain this we develop a stochastic growth model based on multiplicative growth, creation and annihilation. Under the simplifying assumption that these processes do not depend on fund size we obtain a time-dependent analytic solution of the model. The distribution evolves from a log normal into a power law only over long time scales, suggesting that log-normality comes about because the industry is still young and in a transient state due to its rapid growth in recent years. We make the model more realistic by taking into account size dependent effects, in particular the decay in the rates of diffusion and drift with increasing fund size. The resulting model is in good quantitative agreement with the data. Surprisingly, it a...

Schwarzkopf, Yonathan

2008-01-01T23:59:59.000Z

115

SIZE DISTRIBUTIONS OF SOLAR FLARES AND SOLAR ENERGETIC PARTICLE EVENTS  

Science Conference Proceedings (OSTI)

We suggest that the flatter size distribution of solar energetic proton (SEP) events relative to that of flare soft X-ray (SXR) events is primarily due to the fact that SEP flares are an energetic subset of all flares. Flares associated with gradual SEP events are characteristically accompanied by fast ({>=}1000 km s{sup -1}) coronal mass ejections (CMEs) that drive coronal/interplanetary shock waves. For the 1996-2005 interval, the slopes ({alpha} values) of power-law size distributions of the peak 1-8 A fluxes of SXR flares associated with (a) >10 MeV SEP events (with peak fluxes {>=}1 pr cm{sup -2} s{sup -1} sr{sup -1}) and (b) fast CMEs were {approx}1.3-1.4 compared to {approx}1.2 for the peak proton fluxes of >10 MeV SEP events and {approx}2 for the peak 1-8 A fluxes of all SXR flares. The difference of {approx}0.15 between the slopes of the distributions of SEP events and SEP SXR flares is consistent with the observed variation of SEP event peak flux with SXR peak flux.

Cliver, E. W. [Space Vehicles Directorate, Air Force Research Laboratory, Sunspot, NM 88349 (United States); Ling, A. G. [Atmospheric Environmental Research, Lexington, MA 02421 (United States); Belov, A. [IZMIRAN, Troitsk, Moscow Region 142190 (Russian Federation); Yashiro, S. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

2012-09-10T23:59:59.000Z

116

Distance-Scaled Water Concentrations versus Mass-Median Drop Size, Temperature, and Altitude in Supercooled Clouds  

Science Conference Proceedings (OSTI)

About 28 000 nautical miles (n mi) of select in-flight measurements of liquid water content (LWC), droplet sizes, temperature, and other variables in supercooled clouds from a variety of research projects over portions of North America, Europe, ...

Richard K. Jeck

2008-07-01T23:59:59.000Z

117

Microsoft PowerPoint - ARM2007LetterSize.ppt  

NLE Websites -- All DOE Office Websites (Extended Search)

Remote sensing microphysical retrieval and cloud microphysics parameterizations rely on a knowledge of the shape of cloud drop size distributions (DSD). These are often...

118

The Spectral Energy Distribution of HH30 IRS: Constraining The Circumstellar Dust Size Distribution  

E-Print Network (OSTI)

We present spectral energy distribution (SED) models for the edge-on classical T Tauri star HH30 IRS that indicate dust grains have grown to larger than 50 microns within its circumstellar disk. The disk geometry and inclination are known from previous modeling of multiwavelength Hubble Space Telescope images and we use the SED to constrain the dust size distribution. Model spectra are shown for different circumstellar dust models: a standard ISM mixture and larger grain models. As compared to ISM grains, the larger dust grain models have a shallower wavelength dependent opacity. Models with the larger dust grains provide a good match to the currently available data, but mid and far-IR observations are required to more tightly constrain the dust size distribution. The accretion luminosity in our models is L_accdistributions that are simple power-law extensions (i.e., no exponential cutoff) yield acceptable fits to the optical/near-IR but too much emission at mm wavelengths and require larger disk masses. Such a simple size distribution would not be expected in an environment such as the disk of HH30 IRS, particularly over such a large range in grain sizes. However, its ability to adequately characterize the grain populations may be determined from more complete observational sampling of the SED in the mid to far-IR.

Kenneth Wood; Michael J. Wolff; J. E. Bjorkman; Barbara Whitney

2001-09-04T23:59:59.000Z

119

Measurements of Gas Bubble Size Distributions in Flowing Liquid Mercury  

Science Conference Proceedings (OSTI)

ABSTRACT Pressure waves created in liquid mercury pulsed spallation targets have been shown to induce cavitation damage on the target container. One way to mitigate such damage would be to absorb the pressure pulse energy into a dispersed population of small bubbles, however, measuring such a population in mercury is difficult since it is opaque and the mercury is involved in a turbulent flow. Ultrasonic measurements have been attempted on these types of flows, but the flow noise can interfere with the measurement, and the results are unverifiable and often unrealistic. Recently, a flow loop was built and operated at Oak Ridge National Labarotory to assess the capability of various bubbler designs to deliver an adequate population of bubbles to mitigate cavitation damage. The invented diagnostic technique involves flowing the mercury with entrained gas bubbles in a steady state through a horizontal piping section with a glass-window observation port located on the top. The mercury flow is then suddenly stopped and the bubbles are allowed to settle on the glass due to buoyancy. Using a bright-field illumination and a high-speed camera, the arriving bubbles are detected and counted, and then the images can be processed to determine the bubble populations. After using this technique to collect data on each bubbler, bubble size distributions were built for the purpose of quantifying bubbler performance, allowing the selection of the best bubbler options. This paper presents the novel procedure, photographic technique, sample visual results and some example bubble size distributions. The best bubbler options were subsequently used in proton beam irradiation tests performed at the Los Alamos National Laboratory. The cavitation damage results from the irradiated test plates in contact with the mercury are available for correlation with the bubble populations. The most effective mitigating population can now be designed into prototypical geometries for implementation into an actual SNS target.

Wendel, Mark W [ORNL; Riemer, Bernie [ORNL; Abdou, Ashraf A [ORNL

2012-01-01T23:59:59.000Z

120

Estimation of Gamma Raindrop Size Distribution Parameters: Statistical Fluctuations and Estimation Errors  

Science Conference Proceedings (OSTI)

The gamma distribution is often used to characterize raindrop size distributions (DSDs). However, the estimation of measured raindrop distributions suffers from the shortcomings of statistical sampling errors, which become increasingly ...

Cécile Mallet; Laurent Barthes

2009-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

EFFECTS OF SAMPLE SIZE ON CHARACTERIZATION OF WOOD-PARTICLE LENGTH DISTRIBUTION  

E-Print Network (OSTI)

EFFECTS OF SAMPLE SIZE ON CHARACTERIZATION OF WOOD-PARTICLE LENGTH DISTRIBUTION Quang V. Cao of sample size on fitting length distribution of wood particles used for manufacturing wood-based composites moments and the ability of the sample distributions to characterize the population represented

122

Collision, Coalescence and Breakup of Raindrops. Part I: Experimentally Established Coalescence Efficiencies and Fragment Size Distributions in Breakup  

Science Conference Proceedings (OSTI)

The collision, coalescence and breakup of single raindrop pairs were studied at terminal velocities and laboratory pressure (100 kPa) in 761 collision experiments (out of 14 000 attempts). Six size combinations were used with drop pair diameters ...

T. B. Low; Roland List

1982-07-01T23:59:59.000Z

123

On the size distribution of Atlantic tropical cyclones  

E-Print Network (OSTI)

The size of a tropical cyclone is known to vary considerably across storms, though little is understood about the environmental and internal factors that modulate it. Making use of newly available extended tropical cyclone ...

Emanuel, Kerry Andrew

124

High-Resolution Measurement of Size Distributions of Asian Dust Using a Coulter Multisizer  

Science Conference Proceedings (OSTI)

A Coulter Multisizer, which is based on the electrical sensing zone (ESZ) or the Coulter principle, was used to measure the size distribution of Asian dust. Coulter Multisizer analysis provides high-resolution size measurements of water-insoluble ...

Hiroshi Kobayashi; Kimio Arao; Toshiyuki Murayama; Kengo Iokibe; Ryuji Koga; Masataka Shiobara

2007-02-01T23:59:59.000Z

125

The Sensitivity of Microwave Remote Sensing Observations of Precipitation to Ice Particle Size Distributions  

Science Conference Proceedings (OSTI)

This study investigates the effect of variable size distribution and density of precipitation ice particles on microwave brightness temperatures. For this purpose, a set of self-consistent relationships among rain rate, size parameters of an ...

Ralf Bennartz; Grant W. Petty

2001-03-01T23:59:59.000Z

126

Size Distribution of Coastal Aerosols: Effects of Local Sources and Sinks  

Science Conference Proceedings (OSTI)

Using aerosol optical depth as a function of wavelength obtained from ground-based multiwavelength radiometer observations, columnar size-distribution functions of aerosols have been derived. It has been found that the nature of the derived size-...

K. Krishna Moorthy; Prabha R. Nair; B. V. Krishna Murthy

1991-06-01T23:59:59.000Z

127

On the Form of Stationary Size Distributions Established by Coagulation and Sedimentation  

Science Conference Proceedings (OSTI)

In stationary solutions of the equations for nucleation, coagulation and sedimentation, the concentration of large particles falls off more strongly than any power of particle size. The tails of stationary size distributions established by these ...

Warren H. White

1983-07-01T23:59:59.000Z

128

Distributions of Raindrop Sizes and Fall Velocities in a Semiarid Plateau Climate: Convective versus Stratiform Rains  

Science Conference Proceedings (OSTI)

Joint size and fall velocity distributions of raindrops were measured with a Particle Size and Velocity (PARSIVEL) precipitation particle disdrometer in a field experiment conducted during July and August 2007 at a semiarid continental site ...

Shengjie Niu; Xingcan Jia; Jianren Sang; Xiaoli Liu; Chunsong Lu; Yangang Liu

2010-04-01T23:59:59.000Z

129

A New Mechanism of Droplet Size Distribution Broadening during Diffusional Growth  

Science Conference Proceedings (OSTI)

A new mechanism has been developed for size distribution broadening toward large droplet sizes. This mechanism may explain the rapid formation of large cloud droplets, which may subsequently trigger precipitation formation through the collision–...

Alexei Korolev; Mark Pinsky; Alex Khain

2013-07-01T23:59:59.000Z

130

Natural Variations in the Analytical Form of the Raindrop Size Distribution  

Science Conference Proceedings (OSTI)

Empirical analyses are shown to imply variation in the shape or analytical form of the raindrop size distribution consistent with that observed experimentally and predicted theoretically. These natural variations in distribution shape are ...

Carlton W. Ulbrich

1983-10-01T23:59:59.000Z

131

Measurements of Aerosol Size Distributions in the Lower Troposphere over Northern Europe  

Science Conference Proceedings (OSTI)

Airborne measurements of particle size distributions were made at several altitudes within and above the mixing layer at sites near Ahlhorn and Meppen (West Germany), Rodby (Denmark), and Bruz (France). The distributions were measured over the ...

Bruce W. Fitch; Ted S. Cress

1981-10-01T23:59:59.000Z

132

The Modified Gamma Size Distribution Applied to Inhomogeneous and Nonspherical Particles: Key Relationships and Conversions  

Science Conference Proceedings (OSTI)

The four-parameter modified gamma distribution (MGD) is the most general mathematically convenient model for size distributions of particle types ranging from aerosols and cloud droplets or ice particles to liquid and frozen precipitation. The ...

Grant W. Petty; Wei Huang

2011-07-01T23:59:59.000Z

133

Size Distributions and Dynamical Properties of Shallow Cumulus Clouds from Aircraft Observations and Satellite Data  

Science Conference Proceedings (OSTI)

In this paper aircraft observations of shallow cumulus over Florida during the Small Cumulus Microphysics Study (SCMS) are analyzed. Size distributions of cloud fraction, mass flux, and in-cloud buoyancy flux are derived. These distributions ...

Stefaan M. A. Rodts; Peter G. Duynkerke; Harm J. J. Jonker

2003-08-01T23:59:59.000Z

134

Retrieval of Raindrop Size Distribution from Simulated Dual-Frequency Radar Measurements  

Science Conference Proceedings (OSTI)

Observations of raindrop size distributions (DSDs) have validated the use of three-parameter distribution functions in representing the observed spectra. However, dual-frequency radar measurements are limited to retrieving two independent ...

S. Joseph Munchak; Ali Tokay

2008-01-01T23:59:59.000Z

135

Diagnosing the Intercept Parameter for Exponential Raindrop Size Distribution Based on Video Disdrometer Observations: Model Development  

Science Conference Proceedings (OSTI)

The exponential distribution N(D) = N0 exp(??D) with a fixed intercept parameter N0 is most commonly used to represent raindrop size distribution (DSD) in rainfall estimation and in single-moment bulk microphysics parameterization schemes. ...

Guifu Zhang; Ming Xue; Qing Cao; Daniel Dawson

2008-11-01T23:59:59.000Z

136

GA based energy loss minimization approach for optimal sizing & placement of distributed generation  

Science Conference Proceedings (OSTI)

Distributed Generators (DG) provide the lowest cost solution to handle low voltage or overload problems. In conjunction with such problems, a technique of energy saving is introduced by placement of distributed generation (DG) in distribution systems. ... Keywords: Distributed generation (DG), energy saving, genetic algorithms (GA), optimal sizing and placement

Deependra Singh; Devender Singh; K. S. Verma

2008-04-01T23:59:59.000Z

137

Experimental Characterization of BORAL® Pore Size and Volume Distributions  

Science Conference Proceedings (OSTI)

This study has measured pore size and pore volume of six different production batches of BORAL. The study included production lots that are known for being either blister prone or blister resistant under simulated canister wetting/vacuum drying conditions, or known to form edge blisters while in the spent-fuel pool. Additional production lots for which blister performance is unknown also were tested. Blisters in the cladding of BORAL, if large enough, can deform stainless steel walls in storage racks and...

2010-12-10T23:59:59.000Z

138

Sieveless particle size distribution analysis of particulate materials through computer vision  

Science Conference Proceedings (OSTI)

This paper explores the inconsistency of ''length-based separation'' by mechanical sieving of particulate materials with standard sieves, which is the standard method of particle size distribution (PSD) analysis. We observed inconsistencies of length-based ... Keywords: Biomass sieve analysis, Dimension, Image processing, ImageJ plugin, Particle size distribution, Physical property

C. Igathinathane; L. O. Pordesimo; E. P. Columbus; W. D. Batchelor; S. Sokhansanj

2009-05-01T23:59:59.000Z

139

Aerosol size distribution using Lidar data and a typical Lidar assembly  

Science Conference Proceedings (OSTI)

An algorithm is developed and detailed in this paper which determines atmospheric aerosol parameters such as backscatter and extinction coefficients, aerosol optical thickness, and the aerosol size distribution. The algorithm uses the power profile data ... Keywords: LIDAR system, aerosol optical depth, aerosol size distribution, remote sensing

Hamed Parsiani; Javier Mèndez

2008-11-01T23:59:59.000Z

140

Ant Colony System-Based Algorithm for Optimal Multi-stage Planning of Distribution Transformer Sizing  

Science Conference Proceedings (OSTI)

This paper proposes a stochastic optimization method, based on ant colony optimization, for the optimal choice of transformer sizes to be installed in a distribution network. This method is properly introduced to the solution of the optimal transformer ... Keywords: Ant Colony Optimization, Distribution Network Planning, Energy Loss Cost, Optimal Transformer Sizing, Thermal Loading, Transformers

Eleftherios I. Amoiralis; Pavlos S. Georgilakis; Marina A. Tsili; Antonios G. Kladas

2008-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Journal of Molecular Catalysis A: Chemical 228 (2005) 299307 Complementary methods for cluster size distribution measurements  

E-Print Network (OSTI)

size distribution measurements: supported platinum nanoclusters in methane reforming catalysts J.V. All rights reserved. Keywords: Cluster size; SAXS; XAFS; HRTEM; Methane reforming 1. Introduction cluster size strongly influences the reactivity of surfaces for C H bond activation during CH4 steam

Iglesia, Enrique

142

What is the upper size limit for cosmopolitan distribution in free-living microorganisms?  

E-Print Network (OSTI)

What is the upper size limit for cosmopolitan distribution in free-living microorganisms? ABSTRACT distance apart) is used to try and answer the question `What is the upper size limit for cosmopolitan to 230 lm while the largest cosmopolitan species was 135 lm in size. Comparison of the testate

Brown, Richard

143

Statistics of Drop Size Distribution Parameters and Rain Rates for Stratiform and Convective Precipitation during the North Australian Wet Season  

Science Conference Proceedings (OSTI)

C-band polarimetric radar measurements spanning two wet seasons are used to study the effects of the large-scale environment on the statistical properties of stratiform and convective rainfall around Darwin, Australia. The rainfall physical ...

Guillaume Penide; Vickal V. Kumar; Alain Protat; Peter T. May

2013-09-01T23:59:59.000Z

144

Combined Use of the Radar and Radiometer of TRMM to Estimate the Influence of Drop Size Distribution on Rain Retrievals  

Science Conference Proceedings (OSTI)

A combination of passive microwave and radar observations from the Tropical Rainfall Measuring Mission (TRMM) satellite is used to investigate the consistency between the two sensors. Rather than relying on some absolute “truth” to verify ...

Nicolas Viltard; Christian Kummerow; William S. Olson; Ye Hong

2000-12-01T23:59:59.000Z

145

CPOL Radar-Derived Drop Size Distribution Statistics of Stratiform and Convective Rain for Two Regimes in Darwin, Australia  

Science Conference Proceedings (OSTI)

This note builds on prior technique development related to the classification of rain types utilizing C-band polarimetric (CPOL) radar measurements. While the prior work was preliminary and limited in scope, the authors elaborate here on the ...

M. Thurai; V. N. Bringi; P. T. May

2010-05-01T23:59:59.000Z

146

Siting and sizing of distributed generation units using GA and OPF  

Science Conference Proceedings (OSTI)

This paper deals with the important task of finding the optimal siting and sizing of Distributed Generation (DG) units for a given distribution network so that the cost of active and reactive power generation can be minimized. The optimization technique ... Keywords: distributed generation, genetic alghorithm(GA), optimal power flow(OPF)

M. Hosseini Aliabadi; M. Mardaneh; B. Behbahan

2008-01-01T23:59:59.000Z

147

Physicochemical Characterization of Capstone Depleted Uranium Aerosols II: Particle Size Distributions as a Function of Time  

SciTech Connect

The Capstone Depleted Uranium (DU) Aerosol Study, which generated and characterized aerosols containing depleted uranium from perforation of armored vehicles with large-caliber DU penetrators, incorporated a sampling protocol to evaluated particle size distributions. Aerosol particle size distribution is an important parameter that influences aerosol transport and deposition processes as well as the dosimetry of the inhaled particles. These aerosols were collected on cascade impactor substrates using a pre-established time sequence following the firing event to analyze the uranium concentration and particle size of the aerosols as a function of time. The impactor substrates were analyzed using beta spectrometry, and the derived uranium content of each served as input to the evaluation of particle size distributions. Activity median aerodynamic diameters (AMADs) of the particle size distributions were evaluated using unimodal and bimodal models. The particle size data from the impactor measurements was quite variable. Most size distributions measured in the test based on activity had bimodal size distributions with a small particle size mode in the range of between 0.2 and 1.2 um and a large size mode between 2 and 15 um. In general, the evolution of particle size over time showed an overall decrease of average particle size from AMADs of 5 to 10 um shortly after perforation to around 1 um at the end of the 2-hr sampling period. The AMADs generally decreased over time because of settling. Additionally, the median diameter of the larger size mode decreased with time. These results were used to estimate the dosimetry of inhaled DU particles.

Cheng, Yung-Sung; Kenoyer, Judson L.; Guilmette, Raymond A.; Parkhurst, MaryAnn

2009-03-01T23:59:59.000Z

148

Dust Grain-Size Distributions From MRN to MEM  

E-Print Network (OSTI)

Employing the Maximum Entropy Method algorithm, we fit interstellar extinction measurements which span the wavelength range 0.125-3 micron. We present a uniform set of MEM model fits, all using the same grain materials, optical constants and abundance constraints. In addition, we are taking advantage of improved UV and IR data and better estimates of the gas-to-dust ratio. The model fits cover the entire range of extinction properties that have been seen in the Galaxy and the Magellanic Clouds. The grain models employed for this presentation are the simplistic homogeneous spheres models (i.e., Mathis, Rumpl, & Nordsieck 1977) with two (graphite, silicate) or three (graphite, silicate, amorphous carbon) components. Though such usage is only a first step, the results do provide interesting insight into the use of grain size as a diagnostic of dust environment. We find that the SMC Bar extinction curve cannot be fit using carbon grains alone. This is a challenge to the recent observational result indicating little silicon depletion in the SMC.

Geoffrey C. Clayton; Michael J. Wolff; Ulysses J. Sofia; K. D. Gordon; K. A. Misselt

2003-01-24T23:59:59.000Z

149

The dune size distribution and scaling relations of barchan dune fields  

E-Print Network (OSTI)

Barchan dunes emerge as a collective phenomena involving the generation of thousands of them in so called barchan dune fields. By measuring the size and position of dunes in Moroccan barchan dune fields, we find that these dunes tend to distribute uniformly in space and follow an unique size distribution function. We introduce an analyticalmean-field approach to show that this empirical size distribution emerges from the interplay of dune collisions and sand flux balance, the two simplest mechanisms for size selection. The analytical model also predicts a scaling relation between the fundamental macroscopic properties characterizing a dune field, namely the inter-dune spacing and the first and second moments of the dune size distribution.

Orencio Durán; Veit Schwämmle; Pedro G. Lind; Hans J. Herrmann

2007-01-16T23:59:59.000Z

150

Retrieval of Raindrop Size Distributions Using Two Doppler Wind Profilers: Model Sensitivity Testing  

Science Conference Proceedings (OSTI)

The behavior of precipitation is of great importance in obtaining a better understanding of heat transport estimates and global processes in the atmosphere. This paper discusses improvements in an earlier raindrop size distribution model that ...

W. B. Maguire II; S. K. Avery

1994-12-01T23:59:59.000Z

151

Variability of Raindrop Size Distributions in a Squall Line and Implications for Radar Rainfall Estimation  

Science Conference Proceedings (OSTI)

The intrastorm variability of raindrop size distributions as a source of uncertainty in single-parameter and dual-parameter radar rainfall estimates is studied using time series analyses of disdrometer observations. Two rain-rate (R) estimators ...

Remko Uijlenhoet; Matthias Steiner; James A. Smith

2003-02-01T23:59:59.000Z

152

Relationships between the Raindrop Size Distribution and Properties of the Environment and Clouds Inferred from TRMM  

Science Conference Proceedings (OSTI)

Raindrop size distribution (DSD) retrievals from two years of data gathered by the Tropical Rainfall Measuring Mission (TRMM) satellite and processed with a combined radar–radiometer algorithm over the oceans equatorward of 35° are examined for ...

S. Joseph Munchak; Christian D. Kummerow; Gregory Elsaesser

2012-04-01T23:59:59.000Z

153

A Generalized Systems Theory for the Effect of Varying Fluctuations on Cloud Droplet Size Distributions  

Science Conference Proceedings (OSTI)

A systems theory has previously been developed by Liu and Hallett to interpret droplet size distributions in turbulent clouds by utilizing ideas from statistical physics and information theory. The present paper generalizes that systems theory to ...

Yangang Liu; Peter H. Daum; John Hallett

2002-07-01T23:59:59.000Z

154

A Preliminary Analysis of Spatial Variability of Raindrop Size Distributions during Stratiform Rain Events  

Science Conference Proceedings (OSTI)

The spatial variability of raindrop size distributions (DSDs) and precipitation fields is investigated utilizing disdrometric measurements from the four Precipitation Occurrence Sensor Systems (POSS) and radar reflectivity fields from S-band dual-...

Choong Ke Lee; Gyu Won Lee; Isztar Zawadzki; Kyung-Eak Kim

2009-02-01T23:59:59.000Z

155

Progress on Predicting the Breadth of Droplet Size Distributions Observed in Small Cumuli  

Science Conference Proceedings (OSTI)

A modeling framework representing variations in droplet growth by condensation, resulting from different saturation histories experienced as a result of entrainment and mixing, is used to predict the breadth of droplet size distributions observed ...

Jennifer L. Bewley; Sonia Lasher-Trapp

2011-12-01T23:59:59.000Z

156

Improvements of Droplet Size Distribution Measurements with the Fast-FSSP (Forward Scattering Spectrometer Probe)  

Science Conference Proceedings (OSTI)

The basics of single particle measurements are discussed and illustrated with measurements of the droplet size distribution with an optical spectrometer, the Forward Scattering Spectrometer Probe (FSSP), and its improved version, the Fast-FSSP. ...

Jean-Louis Brenguier; Thierry Bourrianne; Afraniode Araujo Coelho; Jacques Isbert; Robert Peytavi; Dominique Trevarin; Perry Weschler

1998-10-01T23:59:59.000Z

157

Air Entrainment Processes and Bubble Size Distributions in the Surf Zone  

Science Conference Proceedings (OSTI)

A new optical instrument was deployed in the surf zone in a trial experiment to measure bubble size distributions and visualize air entrainment and bubble formation mechanisms within breaking surf. Images of bubbles and the evolving air–water ...

Grant B. Deane; M. Dale Stokes

1999-07-01T23:59:59.000Z

158

Raindrop Size Distribution and Radar Parameters in Coastal Tropical Rain Systems of Northeastern Brazil  

Science Conference Proceedings (OSTI)

A dataset on raindrop size distribution (DSD) gathered in a coastal site of the Alagoas state in northeastern Brazil is used to analyze some differences between continental and maritime rainfall parameters. The dataset is divided into two subsets. ...

Ricardo Sarmento Tenório; Marcia Cristina da Silva Moraes; Henri Sauvageot

2012-11-01T23:59:59.000Z

159

Wavenumber Analysis of Azimuthally Distributed Data: Assessing Maximum Allowable Gap Size  

Science Conference Proceedings (OSTI)

Performing wavenumber decomposition on azimuthally distributed data such as those in tropical cyclones can be challenging when data gaps exist in the signal. In the literature, ad hoc approaches are found to determine maximum gap size beyond which ...

Sylvie Lorsolo; Altu? Aksoy

2012-06-01T23:59:59.000Z

160

A Free-Flooding Acoustical Resonator for Measurement of Bubble Size Distributions  

Science Conference Proceedings (OSTI)

An instrument for the measurement of bubble size distributions is described. The sensing element exploits the free-flooding resonator design of Medwin with modifications to overcome the limitations in the original implementation, especially those ...

David M. Farmer; Svein Vagle; A. Donald Booth

1998-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

The Use of Direct Observations over the Aerosol Particle Size Distribution for Inverting Lidar Data  

Science Conference Proceedings (OSTI)

The work is concerned with the inversion of horizontal lidar data into the aerosol particle size distribution (APSD). The aerosol is assumed to consist of spherical particles of continental and oceanic origin. The particular refraction index is ...

Kusiel S. Shifrin; Ilia G. Zolotov

2003-10-01T23:59:59.000Z

162

Dust negative ion acoustic shock waves considering dust size distribution effect  

Science Conference Proceedings (OSTI)

A multi-ion dusty plasma containing hot isothermal electrons, ions (light positive ions and heavy negative ions), and extremely and negatively charged dust grains is studied in the present paper. The dust negative ion acoustic shock waves have been investigated by employing the reductive perturbation method. How the dust size distribution affects the height and the thickness of the nonlinear shock wave is studied. It is noted that the different dust size distribution has different shock wave form and different moving speed.

Ma Yirong; Wang Canglong; Zhang Jianrong; Sun Jianan; Duan Wenshan [College of Physics and Electronic Engineering and Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Northwest Normal University, Lanzhou 730070, China and Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Yang Lei [College of Physics and Electronic Engineering and Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Northwest Normal University, Lanzhou 730070 (China) and Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Department of Physics, Lanzhou University, Lanzhou 730000 (China)

2012-11-15T23:59:59.000Z

163

The Shape–Slope Relation in Observed Gamma Raindrop Size Distributions: Statistical Error or Useful Information?  

Science Conference Proceedings (OSTI)

The three-parameter gamma distribution n(D) = N0Dµ exp(–?D) is often used to characterize a raindrop size distribution (DSD). The parameters µ and ? correspond to the shape and slope of the DSD. If µ and ? are related to one another, as recent ...

Guifu Zhang; J. Vivekanandan; Edward A. Brandes; Robert Meneghini; Toshiaki Kozu

2003-08-01T23:59:59.000Z

164

The E ect of Heavy-Tailed Job Size Distributions on Computer System Design.  

E-Print Network (OSTI)

The E ect of Heavy-Tailed Job Size Distributions on Computer System Design. Mor Harchol-Balter Laboratory for Computer Science MIT, NE43-340 Cambridge, MA 02139 harchol@theory.lcs.mit.edu Abstract Heavy physical phenomena to sociological phenomena. Recently heavy-tailed distributions have been discovered

Harchol-Balter, Mor

165

A POSSIBLE DIVOT IN THE SIZE DISTRIBUTION OF THE KUIPER BELT'S SCATTERING OBJECTS  

Science Conference Proceedings (OSTI)

Via joint analysis of a calibrated telescopic survey, which found scattering Kuiper Belt objects, and models of their expected orbital distribution, we explore the scattering-object (SO) size distribution. Although for D > 100 km the number of objects quickly rise as diameters decrease, we find a relative lack of smaller objects, ruling out a single power law at greater than 99% confidence. After studying traditional ''knees'' in the size distribution, we explore other formulations and find that, surprisingly, our analysis is consistent with a very sudden decrease (a divot) in the number distribution as diameters decrease below 100 km, which then rises again as a power law. Motivated by other dynamically hot populations and the Centaurs, we argue for a divot size distribution where the number of smaller objects rises again as expected via collisional equilibrium. Extrapolation yields enough kilometer-scale SOs to supply the nearby Jupiter-family comets. Our interpretation is that this divot feature is a preserved relic of the size distribution made by planetesimal formation, now ''frozen in'' to portions of the Kuiper Belt sharing a ''hot'' orbital inclination distribution, explaining several puzzles in Kuiper Belt science. Additionally, we show that to match today's SO inclination distribution, the supply source that was scattered outward must have already been vertically heated to the of order 10 Degree-Sign .

Shankman, C.; Gladman, B. J. [Department of Physics and Astronomy, University of British Columbia, 6224 Agriculture Road, Vancouver, BC V6T 1Z1 (Canada); Kaib, N. [Department of Physics and Astronomy, Queens University (Canada); Kavelaars, J. J. [National Research Council of Canada, Victoria, BC V9E 2E7 (Canada); Petit, J. M. [Institut UTINAM, CNRS-Universite de Franche-Comte, Besancon (France)

2013-02-10T23:59:59.000Z

166

Measurements of Aerosol Charge and Size Distribution for Graphite, Gold, Palladium, and Silver Nanoparticles  

Science Conference Proceedings (OSTI)

The role of charge on aerosol evolution and hence the nuclear source term has been an issue of interest, and there is a need for both experimental techniques and modeling for quantifying this role. Our focus here is on further exploration of a tandem differential mobility analyzer (TDMA) technique to simultaneously measure both the size and charge (positive, negative and neutral) dependent aerosol distributions. We have generated graphite, gold, silver, and palladium nanoparticles (aerosol) using a spark generator. We measure the electrical mobility-size distributions for these aerosols using a TDMA, and from these data we deduce the full charge-size distributions. We observe asymmetry in the particle size distributions for negative and positive charges. This asymmetry could have a bearing on the dynamics of charged aerosols, indicating that the assumption of symmetry for size distributions of negatively and positively charged particles in source term simulations may not be always appropriate. Also, the experimental technique should find applications in measurements of aerosol rate processes that are affected by both particle charge and size (e.g. coagulation, deposition, resuspension), and hence in modeling and simulation of the nuclear source term.

Simones, Matthew P.; Gutti, Veera R.; Meyer, Ryan M.; Loyalka, Sudarshan K.

2011-11-01T23:59:59.000Z

167

Particle size distributions of ground corn and DDGS from dry grind processing  

E-Print Network (OSTI)

ABSTRACT. Ethanol production has increased in the past decade as a result of growth in the dry grind industry. In the dry grind process, the first step is grinding of corn. The particle size of the resulting ground corn can affect the fermentation process and the particle size of dried distillers ’ grains with solubles (DDGS), a coproduct of dry grind processing. Few data are available that characterize particle size distributions of ground corn or DDGS. The objective was to determine particle size distributions of ground corn and DDGS. Samples of ground corn and DDGS were obtained from nine dry grind plants; particle size distribution, geometric mean diameter (dgw) and geometric standard deviation (Sgw) were determined. The dgw of ground corn and of DDGS were not different among processing plants. The overall mean dgw of ground corn was not different from that of DDGS. Most of the ground corn (80 g/100 g) and DDGS (70 g/100 g) were recovered in the three largest particle size categories. The particle size distributions of ground corn were not correlated (r Corn, DDGS, Distillers dried grains with solubles, Ethanol. Corn is processed into ethanol by one of two major processes: dry grinding or wet milling. Wet milling is more complex than dry grinding because fiber and germ components are separated; this requires considerable equipment and capital. In the dry grind process,

K. D. Rausch; R. L. Belyea; M. R. Ellersieck; V. Singh; D. B. Johnston; M. E. Tumbleson

2005-01-01T23:59:59.000Z

168

Grain size distributions and photo-electric heating in ionized media  

E-Print Network (OSTI)

Ever since the pioneering study of Spitzer, it has been widely recognized that grains play an important role in the heating and cooling of photo-ionized environments. A detailed code is necessary to model grains in a photo-ionized medium. In this paper we will use the spectral synthesis code Cloudy for this purpose. The grain model of this code has recently undergone a comprehensive upgrade. Part of this is the newly developed hybrid grain charge model, which will be described in detail. This model allows discrete charge states of very small grains to be modelled accurately while simultaneously avoiding the overhead of fully resolving the charge distribution of large grains, thus making the model both accurate and computationally efficient. A comprehensive comparison with the fully resolved charge state models of Weingartner & Draine (2001) shows that the agreement is very satisfactory for realistic size distributions. The effect of the grain size distribution on the line emission from photo-ionized regions is studied by taking standard models for an H II region and a planetary nebula and adding a dust component to the models with varying grain size distributions. A comparison of the models shows that varying the size distribution has a dramatic effect on the emitted spectrum, and affects the ionization balance as well. These results clearly demonstrate that the grain size distribution is an important parameter in photo-ionization models.

P. A. M. van Hoof; J. C. Weingartner; P. G. Martin; K. Volk; G. J. Ferland

2004-02-16T23:59:59.000Z

169

Standard Test Method for Particle Size Distribution of Alumina or Quartz Powders by Electrical Sensing Zone Technique  

E-Print Network (OSTI)

Standard Test Method for Particle Size Distribution of Alumina or Quartz Powders by Electrical Sensing Zone Technique

American Society for Testing and Materials. Philadelphia

1992-01-01T23:59:59.000Z

170

EVOLUTION OF SIZE DISTRIBUTION OF ICY GRAINS BY SUBLIMATION AND CONDENSATION  

SciTech Connect

In the outer part of a protoplanetary disk, dust grains consist of silicate core covered by an ice mantle. A temporal heating event in the disk results in sublimation of the ice mantle. After the end of the heating event, as the temperature decreases, H{sub 2}O molecules recondense on the surface of the dust grain. Ultimately, the dust grain is covered by an ice mantle. Because the equilibrium vapor pressure on the grain surface decreases with the grain size, a large grain grows faster than a small grain. As a result, the size of an icy dust grain changes as a result of the heating event. The change in size also affects the mechanical properties of the dust aggregates formed by the icy grains. In this paper, we investigated the evolution of the size distribution of icy dust grains during sublimation and condensation. We found that the size evolution of icy grains can be divided into two stages. In the first stage, the icy grains grow through condensation of H{sub 2}O molecules. In the second stage, the size of grains changes further as H{sub 2}O molecules are transferred between icy grains while the surrounding gas condenses. The size distribution of the icy dust grains becomes bimodal, with a small number of relatively large grains and many small grains without an icy mantle. Possible effects of the size change on the evolution of icy dust aggregates are discussed.

Kuroiwa, Takuto; Sirono, Sin-iti [Earth and Environmental Sciences, Graduate School of Environmental Studies, Nagoya University, Nagoya 464-8601 (Japan)

2011-09-20T23:59:59.000Z

171

Finite Size Effects on the Real-Space Pair Distribution Function of Nanoparticles  

SciTech Connect

The pair distribution function (PDF) method is a powerful approach for the analysis of the structure of nanoparticles. An important approximation used in nanoparticle PDF simulations is the incorporation of a form factor describing nanoparticle size and shape. The precise effect of the form factor on the PDF is determined by both particle shape and structure if these characteristics are both anisotropic and correlated. The correct incorporation of finite size effects is important for distinguishing and quantifying the structural consequences of small particle size in nanomaterials.

Gilbert, Benjamin

2008-10-01T23:59:59.000Z

172

Interfacial energy effects and the evolution of pore size distributions during quartz precipitation in sandstone  

E-Print Network (OSTI)

Interfacial energy effects and the evolution of pore size distributions during quartz precipitation-scale to nanometer scale pores, interfacial energy (surface energy) effects can also become important. Interfacial energy typically increases the solubility of very small crystals growing in tiny pores, and when

Simon, Emmanuel

173

Description of sprays using joint hyperbolic distribution in particle size and velocity  

SciTech Connect

The joint probability density functions of droplet size and velocity have been represented in sprays by the two-dimensional hyperbolic distribution. A distribution is provided, and a procedure to compute its eight parameters outlined. Analytical expressions for certain statistical quantities, such as mean diameters, momentum, kinetic energy etc., applicable under certain restrictions, are obtained. The computations for a water spray issuing from a Danfoss 60{degrees} solid cone oil-burner nozzle demonstrate not only that the hyperbolic distribution provides an excellent approximation for the joint size and velocity distributions for the measurements taken along the entire length of the spray axis, but also that such representation presents a clear insight into the physics of the motion and the related size formation. The computations reveal a developing region, with areas dominated by breakup or coalescence of droplets, followed by a developed state with little change in droplet size but continuously decreasing velocity. It is concluded that this novel approach is well suited to the description of sprays.

Bhatia, J.C.; Durst, F. (LSTM-Erlangen, Lehrstuhl fur Stromungsmechanik, Universitat Erlangen-Nurnberg, 8520 Erlangen (DE))

1990-09-01T23:59:59.000Z

174

Influence of the Subgrid Variability of the Raindrop Size Distribution on Radar Rainfall Estimators  

Science Conference Proceedings (OSTI)

This work aims at quantifying the variability of the parameters of the power laws used for rain-rate estimation from radar data, on the basis of raindrop size distribution measurements over a typical weather radar pixel. Power laws between the ...

Joël Jaffrain; Alexis Berne

2012-04-01T23:59:59.000Z

175

An Experimental Study of Small-Scale Variability of Raindrop Size Distribution  

Science Conference Proceedings (OSTI)

An experimental study of small-scale variability of raindrop size distributions (DSDs) has been carried out at Wallops Island, Virginia. Three Joss–Waldvogel disdrometers were operated at a distance of 0.65, 1.05, and 1.70 km in a nearly straight ...

Ali Tokay; Paul G. Bashor

2010-11-01T23:59:59.000Z

176

The Dependence of Cirrus Cloud-Property Retrievals on Size-Distribution  

NLE Websites -- All DOE Office Websites (Extended Search)

The Dependence of Cirrus Cloud-Property Retrievals on Size-Distribution The Dependence of Cirrus Cloud-Property Retrievals on Size-Distribution Shape d'Entremont, Robert Atmospheric and Environmental Research, Inc. Mitchell, David Desert Research Institute Category: Cloud Properties Our project has focused on using satellite- and ground-based passive thermal infrared radiance observations to retrieve cirrus cloud properties, most importantly ice water path (IWP), effective particle size (Deff), and visible extinction optical thickness (tau). During this past year we began comparing our cirrus retrieval results with aircraft observations at the ARM CART site, and we are participating in a summary intercomparison study with other retrieval algorithms as a member of the high-clouds working group. Our passive-infrared retrieval scheme, based on different wavelength

177

The Occurrence of Particle Size Distribution Bimodality in Midlatitude Cirrus as Inferred from Ground-Based Remote Sensing Data  

Science Conference Proceedings (OSTI)

Data collected in midlatitude cirrus clouds by instruments on jet aircraft typically show particle size distributions that have distinct distribution modes in both the 10–30-?m maximum dimension (D) size range and the 200–300-?m D size range or ...

Yang Zhao; Gerald G. Mace; Jennifer M. Comstock

2011-06-01T23:59:59.000Z

178

COLOR DEPENDENCE IN THE SIZE DISTRIBUTION OF MAIN BELT ASTEROIDS REVISITED  

SciTech Connect

The size distribution of the asteroid belt is examined with 16956 main belt asteroids detected in data taken from the Canada-France-Hawaii Telescope Legacy Survey in two filters (g' and r'). The cumulative H (absolute magnitude) distribution is examined in both filters, and both match well to simple power laws down to H = 17, with slopes in rough agreement with those reported the literature. This implies that disruptive collisions between asteroids are gravitationally dominated down to at least this size, and probably sub-kilometer scales. The slopes of these distributions appear shallower in the outer belt than the inner belt, and the g' distributions appear slightly steeper than the r'. The slope shallowing in the outer belt may reflect a real compositional difference: the inner asteroid belt has been suggested to consist mostly of stony and/or metallic S-type asteroids, whereas carbonaceous C-types are thought to be more prevalent further from the Sun. No waves are seen in the size distribution above H = 15. Since waves are expected to be produced at the transition from gravitationally-dominated to internal strength-dominated collisions, their absence here may imply that the transition occurs at sub-kilometer scales, much smaller than the H = 17 (diameter {approx} 1.6 km) cutoff of this study.

August, Tyler M.; Wiegert, Paul A., E-mail: tx_august@laurentian.ca [Department of Physics and Astronomy, The University of Western Ontario, London, ON N6A 3K7 (Canada)

2013-06-15T23:59:59.000Z

179

Effects of Nanoparticle Geometry and Size Distribution on Diffusion Impedance of Battery Electrodes  

E-Print Network (OSTI)

The short diffusion lengths in insertion battery nanoparticles render the capacitive behavior of bounded diffusion, which is rarely observable with conventional larger particles, now accessible to impedance measurements. Coupled with improved geometrical characterization, this presents an opportunity to measure solid diffusion more accurately than the traditional approach of fitting Warburg circuit elements, by properly taking into account the particle geometry and size distribution. We revisit bounded diffusion impedance models and incorporate them into an overall impedance model for different electrode configurations. The theoretical models are then applied to experimental data of a silicon nanowire electrode to show the effects of including the actual nanowire geometry and radius distribution in interpreting the impedance data. From these results, we show that it is essential to account for the particle shape and size distribution to correctly interpret impedance data for battery electrodes. Conversely, it...

Song, J

2012-01-01T23:59:59.000Z

180

Grain size distributions and photo-electric heating in ionised media  

E-Print Network (OSTI)

Ever since the pioneering study of Spitzer, it has been widely recognised that grains play an important role in the heating and cooling of photo-ionised environments. A detailed code is necessary to model grains in a photo-ionised medium. In this paper we will use the spectral synthesis code Cloudy for this purpose. The grain model of this code has recently undergone a comprehensive upgrade. Part of this is the newly developed hybrid grain charge model, which will be described in detail. This model allows discrete charge states of very small grains to be modelled accurately while simultaneously avoiding the overhead of fully resolving the charge distribution of large grains, thus making the model both accurate and computationally efficient. A comprehensive comparison with the fully resolved charge state models of Weingartner & Draine (2001) shows that the agreement is very satisfactory for realistic size distributions. The effect of the grain size distribution on the line emission from photo-ionised regio...

Van Hoof, P A M; Martin, P G; Volk, K; Ferland, G J

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Mass Conservation Considerations in Analytic Representation of Raindrop Fragment Distributions  

Science Conference Proceedings (OSTI)

Model formulation of drop breakup requires a set of analytic functions to describe the size distribution of water fragments that result from the collision of two raindrops of arbitrary diameter. The set of fragment distribution functions derived ...

Philip S. Brown Jr.

1997-06-01T23:59:59.000Z

182

Characteristics of inhalable particulate matter concentration and size distribution from power plants in China  

Science Conference Proceedings (OSTI)

The collection efficiency of particulate emission control devices (PECDs), particulate matter (PM) emissions, and PM size distribution were determined experimentally at the inlet and outlet of PECDs at five coal-fired power plants. Different boilers, coals, and PECDs are used in these power plants. Measurement in situ was performed by an electrical low-pressure impactor with a sampling system, which consisted of an isokinetic sampler probe, precut cyclone, and two- stage dilution system with a sample line to the instruments. The size distribution was measured over a range from 0.03 to 10 {mu}m. Before and after all of the PECDs, the particle number size distributions display a bimodal distribution. The PM2.5 fraction emitted to atmosphere includes a significant amount of the mass from the coarse particle mode. The controlled and uncontrolled emission factors of total PM, inhalable PM (PM10), and fine PM (PM2.5) were obtained. Electrostatic precipitator (ESP) and baghouse total collection efficiencies are 96.38 99.89% and 99.94%, respectively. The minimum collection efficiency of the ESP and the baghouse both appear in the particle size range of 0.1 1 0 {mu}m. In this size range, ESP and baghouse collection efficiencies are 85.79 98.6% and 99.54%. Real- time measurement shows that the mass and number concentration of PM10 will be greatly affected by the operating conditions of the PECDs. The number of emitted particles increases with increasing boiler load level because of higher combustion temperature. During test run periods, the data reproducibility is satisfactory. 19 refs., 11 figs., 6 tabs.

Honghong Yi; Jiming Hao; Lei Duan; Xinghua Li; Xingming Guo [Tsinghua University, Beijing (China). Department of Environmental Science and Engineering

2006-09-15T23:59:59.000Z

183

Scale-free Universal Spectrum for Atmospheric Aerosol Size Distribution for Davos, Mauna Loa and Izana  

E-Print Network (OSTI)

Atmospheric flows exhibit fractal fluctuations and inverse power law form for power spectra indicating an eddy continuum structure for the selfsimilar fluctuations. A general systems theory for fractal fluctuations developed by the author is based on the simple visualisation that large eddies form by space-time integration of enclosed turbulent eddies, a concept analogous to Kinetic Theory of Gases in Classical Statistical Physics. The ordered growth of atmospheric eddy continuum is in dynamical equilibrium and is associated with Maximum Entropy Production. The model predicts universal (scale-free) inverse power law form for fractal fluctuations expressed in terms of the golden mean. Atmospheric particulates are held in suspension in the fractal fluctuations of vertical wind velocity. The mass or radius (size) distribution for homogeneous suspended atmospheric particulates is expressed as a universal scale-independent function of the golden mean, the total number concentration and the mean volume radius. Model predicted spectrum is in agreement (within two standard deviations on either side of the mean) with total averaged radius size spectra for the AERONET (aerosol inversions) stations Davos and Mauna Loa for the year 2010 and Izana for the year 2009 daily averages. The general systems theory model for aerosol size distribution is scale free and is derived directly from atmospheric eddy dynamical concepts. At present empirical models such as the log normal distribution with arbitrary constants for the size distribution of atmospheric suspended particulates are used for quantitative estimation of earth-atmosphere radiation budget related to climate warming/cooling trends. The universal aerosol size spectrum will have applications in computations of radiation balance of earth-atmosphere system in climate models.

A. M. Selvam

2011-11-14T23:59:59.000Z

184

The Role of Ice Particle Shapes and Size Distributions in the Single Scattering Properties of Cirrus Clouds  

Science Conference Proceedings (OSTI)

The roles of ice particle size distributions (SDs) and particle shapes in cirrus cloud solar radiative transfer are investigated by analyzing SDs obtained from optical array probe measurements (particle sizes larger than 20–40 ?m) during ...

Andreas Macke; Peter N. Francis; Greg M. McFarquhar; Stefan Kinne

1998-09-01T23:59:59.000Z

185

Field Observations of In-Cloud Nucleation and the Modification of Atmospheric Aerosol Size Distributions after Cloud Evaporation  

Science Conference Proceedings (OSTI)

The authors measured aerosol and droplet size distributions in the range from 0.1 to 50 µm, concentrations and sizes of precipitation particles, concentrations of condensation nuclei, and state parameters in and in the vicinity of a towering ...

A. J. Alkezweeny

1995-12-01T23:59:59.000Z

186

Ion-Drop Interaction During Drop Evaporation  

Science Conference Proceedings (OSTI)

As a basic experiment in warm cloud electrification, evaporating large drops were studied as they floated in an ion-rich environment in a vertical wind tunnel. The drops were found to acquire a positive charge during their evaporation, a result ...

Tsutomu Takahashi; Tatsuo Endoh

1983-02-01T23:59:59.000Z

187

Pore and throat size distributions measured from synchrotron X-ray tomographic images of Fontainebleau sandstones  

E-Print Network (OSTI)

The three-dimensional geometry and connectivity of pore space controls the hydraulic transport behavior of crustal rocks. We report on direct measurement of flow-relevant geometrical properties of the void space in a suite of 4 samples of Fontainebleau sandstone ranging from 7.5% to 22% porosity. The measurements are obtained from computer analysis of three dimensional, synchrotron X-ray computed microtomographic images. We present measured distributions of coordination number, channel length, throat size and pore volume, and of correlations between throat-size/pore-volume and nearest neighbor pore-volume/pore volume determined for these samples. We also present quantitative characterization of the distributions measured. The effects of finite sample volume are investigated. The accuracy of the numerical algorithms employed is investigated using a simulated image of hexagonal closed packed spheres.

W. Brent Lindquist; Arun Venkatarangan; John Dunsmuir; Teng-fong Wong

1999-01-01T23:59:59.000Z

188

Particle size distribution of airborne plutonium near a chemical separations facility  

Science Conference Proceedings (OSTI)

Particulate matter containing Pu-238 and Pu-239,240 emitted from a stack at the Savannah River Plant was collected and fractionated by size with cascade impactors. Two impactor measurements were made at a distance of 200 meters from the H-Area stack and a third was at a distance of 420 meters. Annual collections were made for three years. The Pu-238 and Pu 239,240 concentrations were determined for each of the size fractions. The fractions collected at 200 m from the 62 m stack showed a biphasic curve for both Pu-238 and Pu-239,240. The highest concentration for both Pu-238 and Pu-239,240 were found in the <0.49 ..mu..m fraction, with the secondary peak occurring in the fractions greater than 3.0 ..mu..m. At 420 meters from the stack, the size distribution curves for Pu-238 and Pu-239,240 were not biphasic; only one peak appeared and that was for the fraction less than 0.49 ..mu..m. The doses to different organs from plutonium inhalation were calculated for the particle size distributions obtained in this study. The maximum potential 50-year dose commitment to the bone, the critical organ, for one year continuous exposure was 13 mrem for Pu-238 and 0.44 mrem for Pu-239,240 at 200 meters from the H-Area stack.

Gay, D.D.; Watts, J.R.

1981-12-01T23:59:59.000Z

189

Measured Collection Efficiencies for Cloud Drops  

Science Conference Proceedings (OSTI)

The collection efficiency has been measured for 15 size pairs of relatively uncharged drops in over 400 experimental runs. The results indicate that collection efficiencies fall in a narrow range of 0.60 to 0.70 even though the collector drop was ...

K. V. Beard; Harry T. Ochs III

1983-01-01T23:59:59.000Z

190

Models for Unsaturated Hydraulic Conductivity Based on Truncated Lognormal Pore-size Distributions  

E-Print Network (OSTI)

We develop a closed-form three-parameter model for unsaturated hydraulic conductivity associated with a three-parameter lognormal model of moisture retention, which is based on lognormal grainsize distribution. The derivation of the model is made possible by a slight modification to the theory of Mualem. We extend the three-parameter lognormal distribution to a four-parameter model that also truncates the pore size distribution at a minimum pore radius. We then develop the corresponding four-parameter model for moisture retention and the associated closed-form expression for unsaturated hydraulic conductivity. The four-parameter model is fitted to experimental data, similar to the models of Kosugi and van Genuchten. The proposed four-parameter model retains the physical basis of Kosugi's model, while improving fit to observed data especially when simultaneously fitting pressure-saturation and pressure-conductivity data.

Malama, Bwalya

2013-01-01T23:59:59.000Z

191

Temporal Variations of Aerosol Optical Parameters Resulting from the Aging of a Model Aerosol Number Size Distribution  

Science Conference Proceedings (OSTI)

Aerosol number size distributions are subject to aging, i.e., to temporal variations. The aging of a Junge number size distribution due to a multitude of processes was modeled by Junge and Abel. The pertinent changes with time of aerosol optical ...

J. Freund

1984-04-01T23:59:59.000Z

192

Influence of charging process and size distribution of dust grain on the electric conductivity of dusty plasma  

Science Conference Proceedings (OSTI)

The effects of dust size distribution and charging process of dust grains on the complex electric conductivity of dusty plasmas have been investigated in the present paper. Comparisons are made between real dusty plasma in which there are many different dust grain species and the mono-sized dusty plasma (MDP) in which there is only one kind of dust grain whose size is the average dust size. In some cases the complex electric conductivity of real dusty plasma is larger than that of MDP, while in other cases it is smaller than that of MDP, it depends on the dust size distribution function.

Duan Jizheng; Wang Canglong; Zhang Jianrong; Ma Shengqian; Hong Xueren; Sun Jianan [College of Physics and Electronic Engineering and Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Northwest Normal University, Lanzhou 730070 (China) and Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Duan Wenshan [College of Physics and Electronic Engineering and Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Northwest Normal University, Lanzhou 730070 (China) and Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Yang Lei [College of Physics and Electronic Engineering and Joint Laboratory of Atomic and Molecular Physics of NWNU and IMP CAS, Northwest Normal University, Lanzhou 730070 (China) and Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Department of Physics, Lanzhou University, Lanzhou 730000 (China)

2012-08-15T23:59:59.000Z

193

Continuum representation of a continuous size distribution of particles engaged in rapid granular flow  

Science Conference Proceedings (OSTI)

Natural and industrial granular flows often consist of several particle sizes, approximately forming a continuous particle size distribution (PSD). Continuous PSDs are ubiquitous, though existing kinetic-theory-based, hydrodynamic models for rapid granular flows are limited to a discrete number of species. The objective of this work is twofold: (i) to determine the number of discrete species required to accurately approximate a continuous PSD and (ii) to validate these results via a comparison with molecular dynamics (MD) simulations of continuous PSDs. With regard to the former, several analytic (Gaussian and lognormal) and experimental (coal and lunar soil simulants) distributions are investigated. Transport coefficients (pressure, shear viscosity, etc.) of the granular mixture given by the polydisperse theory of Garz´o et al. [“Enskog theory for polydisperse granular mixtures. I. Navier-Stokes order transport,” Phys. Rev. E 76, 031303 (2007);“Enskog theory for polydisperse granular mixtures. I. Navier-Stokes order transport,” 76, 031304 (2007)] are compared using an increasing number of species s to approximate the given PSD. These discrete approximations are determined by matching the first 2s moments of the approximation and the given continuous distribution. Relatively few species are required to approximate moderately wide distributions (Gaussian, lognormal), whereas even wider distributions (coal and lunar soil simulants) require a larger number of species. Regarding the second objective, a comparison between MD simulations and kinetictheory predictions for a simple shear flow of both Gaussian and lognormal PSDs reveal essentially no loss of accuracy stemming from the polydisperse theory itself (as compared to theories for monodisperse systems) or from the discrete approximations of continuous PSDs used in the polydisperse theory. C #2; 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4744987

Murray, J.A.; Benyahia, S.; Metzger, P.; Hrenya, C.M.

2012-01-01T23:59:59.000Z

194

Multiscale modeling of the influence of Fe content in a Al-Si-Cu alloy on the size distribution of intermetallic phases and micropores  

Science Conference Proceedings (OSTI)

A multiscale model was developed to simulate the formation of Fe-rich intermetallics and pores in quaternary Al-Si-Cu-Fe alloys. At the microscale, the multicomponent diffusion equations were solved for multiphase (liquid-solid-gas) materials via a finite difference framework to predict microstructure formation. A fast and robust decentered plate algorithm was developed to simulate the strong anisotropy of the solid/liquid interfacial energy for the Fe-rich intermetallic phase. The growth of porosity was controlled by local pressure drop due to solidification and interactions with surrounding solid phases, in addition to hydrogen diffusion. The microscale model was implemented as a subroutine in a commercial finite element package, producing a coupled multiscale model. This allows the influence of varying casting conditions on the Fe-rich intermetallics, the pores, and their interactions to be predicted. Synchrotron x-ray tomography experiments were performed to validate the model by comparing the three-dimensional morphology and size distribution of Fe-rich intermetallics as a function of Fe content. Large platelike Fe-rich {beta} intermetallics were successfully simulated by the multiscale model and their influence on pore size distribution in shape castings was predicted as a function of casting conditions.

Wang Junsheng; Lee, Peter D. [Department of Materials, Imperial College London, South Kensington Campus, Prince Consort Road, London SW7 2AZ (United Kingdom); Li Mei; Allison, John [Materials Research and Advanced Engineering Department, Ford Research Laboratory, Dearborn, Michigan 48121-2053 (United States)

2010-03-15T23:59:59.000Z

195

SURFACE AREA, VOLUME, MASS, AND DENSITY DISTRIBUTIONS FOR SIZED BOMASS PARTICLES  

DOE Green Energy (OSTI)

This semi-annual technical progress report describes work performed at Morehouse College under DOE Grant No. DE-FC26-04NT42130 during the period July 01, 2004 to December 31, 2004 which covers the first six months of the project. Presently work is in progress to characterize surface area, volume, mass, and density distributions for sized biomass particles. During this reporting period, supply requests were processed and supplies including biomass test particles (hardwood sawdust AI14546) in the size range of 100-200 microns were obtained from a cofiring pilot plant research facility owned by Southern Company, Birmingham, AL. Morehouse has completed setting up of the gravimetric technique measurement system in the heat transfer laboratory, department of physics and dual degree engineering, Morehouse College. Simultaneously, REM, our subcontractor, has completed setting up of the electrodynamic balance (EDB) measurement system to characterize shape and mass for individual biomass particles. Testing of the gravimetric system, and calibration of the cameras and imaging systems using known sizes of polystyrene particles are in progress.

Ramanathan Sampath

2004-05-01T23:59:59.000Z

196

Sea-Salt Size Distributions from Breaking Waves: Implications for Marine Aerosol Production and Optical Extinction Measurements during SEAS  

Science Conference Proceedings (OSTI)

The authors' participation in the Shoreline Environment Aerosol Study (SEAS) involved measurements focused on the coastal aerosol size distribution and related optical measurements, including aerosol light scattering, visibility, and remote ...

A. Clarke; V. Kapustin; S. Howell; K. Moore; B. Lienert; S. Masonis; T. Anderson; D. Covert

2003-10-01T23:59:59.000Z

197

The grain size distribution and the detection of abnormal grain growth of austenite in an eutectoid steel containing niobium  

SciTech Connect

The abnormal grain growth of austenite was studied in a commercial steel of composition (wt%): 0.70 C, 1.36 Mn, 0.72 Si, 0.015 P, 0.027 S and 0.03 Nb. Specimens were thermocycled at various conditions and then grain size distribution determined. The grain size distribution shape did not change during normal grain growth but this distribution widened and flattened during the abnormal grain growth. The initial smaller mean size of carbonitrides and/or the highest homogeneity of niobium carbonitride size distribution of the samples submitted to thermal cycles, in comparison with the normalized samples, increased the abnormal grain growth temperature from 1,373 K to 1,473 K.

Bruno, J.C. (Instituto Militar de Engenharia, Rio de Janeiro (Brazil). Dept. de Engenharia Mecanica e de Materiais); Rios, P.R. (Pontificia Univ. Catolica do Rio de Janeiro (Brazil). Dept. de Ciencia dos Materiais e Metalurgia)

1995-02-15T23:59:59.000Z

198

Quantification of the Small-Scale Spatial Structure of the Raindrop Size Distribution from a Network of Disdrometers  

Science Conference Proceedings (OSTI)

The spatial structure of the raindrop size distribution (DSD) conveys crucial information for reliable quantitative estimation of rainfall using remote sensing techniques. To investigate this question, a network of 16 optical disdrometers has been ...

Joël Jaffrain; Alexis Berne

2012-05-01T23:59:59.000Z

199

Observations of Saharan Aerosols: Results of ECLATS Field Experiment. Part I: Optical Thicknesses and Aerosol Size Distributions  

Science Conference Proceedings (OSTI)

A series of ground-based and airborne observations of desert aerosols, the ECLATS experiment was carried out in December 1980 in the vicinity of Niamey (Niger). This paper deals with aerosol optical thicknesses and size distributions derived from ...

Y. Fouquart; B. Bonnel; M. Chaoui Roquai; R. Santer; A. Cerf

1987-01-01T23:59:59.000Z

200

The Modification of Joint Size–Charge Distribution in Rain. Part I: Computations which Exclude Partial Coalescence  

Science Conference Proceedings (OSTI)

The effect of individual charge-modifying processes is tested by following the development joint distributions of raindrop size and charge through a fall depth of 1 km beneath a weakly electrified warm cloud. Evaporation, ion capture and ...

S. G. Bradley; C. D. Stow

1984-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Improved Normalization of the Size Distribution of Atmospheric Particles Retrieved from Aureole Measurements Using the Diffraction Approximation  

Science Conference Proceedings (OSTI)

This paper describes an improvement in the diffraction approximation used to retrieve the size distribution of atmospheric particles from solar aureole radiance measurements. Normalization using total optical thickness based on measurement of the ...

J. G. DeVore

2011-08-01T23:59:59.000Z

202

SURFACE AREA, VOLUME, MASS, AND DENSITY DISTRIBUTIONS FOR SIZED BIOMASS PARTICLES  

DOE Green Energy (OSTI)

This semi-annual technical progress report describes work performed at Morehouse College under DOE Grant No. DE-FC26-04NT42130 during the period July 01, 2005 to December 31, 2005 which covers the third six months of the project. Presently work is in progress to characterize surface area, volume, mass, and density distributions for sized biomass particles. During this reporting period, Morehouse continued to obtain additional mean mass measurements for biomass particles employing the gravimetric technique measurement system that was set up in the last reporting period. Simultaneously, REM, our subcontractor, has obtained raw data for surface area, volume, and drag coefficient to mass ratio (C{sub d}/m) information for several biomass particles employing the electrodynamic balance (EDB) measurement system that was calibrated in the last reporting period. Preliminary results of the mean mass and the shape data obtained are reported here, and more data collection is in progress.

Ramanathan Sampath

2006-01-01T23:59:59.000Z

203

SURFACE AREA, VOLUME, MASS, AND DENSITY DISTRIBUTIONS FOR SIZED BIOMASS PARTICLES  

DOE Green Energy (OSTI)

This semi-annual technical progress report describes work performed at Morehouse College under DOE Grant No. DE-FC26-04NT42130 during the period January 01, 2006 to June 30, 2006 which covers the fourth six months of the project. Presently work is in progress to characterize surface area, volume, mass, and density distributions for sized biomass particles. During this reporting period, Morehouse completed obtaining additional mean mass measurements for biomass particles employing the gravimetric technique measurement system that was set up in a previous reporting period. Simultaneously, REM, our subcontractor, has completed obtaining raw data for surface area, volume, and drag coefficient to mass ratio (Cd/m) information for 9 more biomass particles employing the electrodynamic balance (EDB) measurement system that was calibrated before in this project. Results of the mean mass data obtained to date are reported here, and analysis of the raw data collected by REM is in progress.

Ramanathan Sampath

2006-06-30T23:59:59.000Z

204

The sizes and powers of some stochastic dominance tests: A Monte Carlo study for correlated and heteroskedastic distributions  

Science Conference Proceedings (OSTI)

Testing for stochastic dominance among distributions is an important issue in the study of asset management, income inequality, and market efficiency. This paper conducts Monte Carlo simulations to examine the sizes and powers of several commonly used ... Keywords: C12, Correlated distributions, D31, G11, Grid points, Heteroskedasticity, Stochastic dominance

Hooi-Hooi Lean; Wing-Keung Wong; Xibin Zhang

2008-10-01T23:59:59.000Z

205

A General Systems Theory for Atmospheric Flows and Atmospheric Aerosol Size Distribution  

E-Print Network (OSTI)

Atmospheric flows exhibit selfsimilar fractal spacetime fluctuations manifested as the fractal geometry to global cloud cover pattern and inverse power law form for power spectra of meteorological parameters such as windspeed, temperature, rainfall etc. Inverse power law form for power spectra indicate long-range spacetime correlations or non-local connections and is a signature of selforganised criticality generic to dynamical systems in nature such as river flows, population dynamics, heart beat patterns etc. The author has developed a general systems theory which predicts the observed selforganised criticality as a signature of quantumlike chaos in dynamical systems. The model predictions are (i) The fractal fluctuations can be resolved into an overall logarithmic spiral trajectory with the quasiperiodic Penrose tiling pattern for the internal structure. (ii) The probability distribution represents the power (variance) spectrum for fractal fluctuations and follows universal inverse power law form incorporating the golden mean. Such a result that the additive amplitudes of eddies when squared represent probability distribution is observed in the subatomic dynamics of quantum systems such as the electron or photon. Therefore the irregular or unpredictable fractal fluctuations exhibit quantumlike chaos. (iii) Atmospheric aerosols are held in suspension by the vertical velocity distribution (spectrum). The atmospheric aerosol size spectrum is derived in terms of the universal inverse power law characterizing atmospheric eddy energy spectrum. Model predicted spectrum is in agreement with the following two experimentally determined atmospheric aerosol data sets, (i) SAFARI 2000 CV-580 Aerosol Data, Dry Season 2000 (CARG) (ii) World Data Centre Aerosols data sets for the three stations Ny {\\AA}lesund, Pallas and Hohenpeissenberg.

A. M. Selvam

2009-08-17T23:59:59.000Z

206

Lifetime of oil drops pressed by buoyancy against a planar interface: Large drops  

E-Print Network (OSTI)

In a previous report [10] it was shown that emulsion stability simulations are able to reproduce the lifetime of micrometer-size drops of hexadecane pressed by buoyancy against a planar water-hexadecane interface. It was confirmed that small drops (rioil stabilized with bovine serum albumin. The potential obtained is then employed to study the lifetime of deformable drops in the range 10 \\leq ri \\leq 1000 {\\mu}m. It is established that the average lifetime of these drops can be adequately replicated using the model of truncated spheres. However, the results depend sensibly on the expressions of the initial distance of deformation and the maximum film radius used in the calculations. The set of equations adequate for large drops is not satisfactory for medium-size drops (10 \\leq ri \\leq 100 {\\mu}m), and vice versa. In the case of large particles, the increase in the interfacial area as a consequence of the deformation of the drops generates a very large repulsive barrier which opposes coalescence. Nevertheless, the buoyancy force prevails. As a consequence, it is the hydrodynamic tensor of the drops which determine the characteristic behavior of the lifetime as a function of the particle size. While the average values of the coalescence time of the drops can be justified by the mechanism of film thinning, the scattering of the experimental data of large drops cannot be rationalized using the methodology previously described. A possible explanation of this phenomenon required elaborate simulations which combine deformable drops, capillary waves, repulsive interaction forces, and a time-dependent surfactant adsorption.

Clara Rojas; Máximo García-Sucre; Germán Urbina-Villalba

2010-12-15T23:59:59.000Z

207

Surface Area, Volume, Mass, and Density Distributions for Sized Biomass Particles  

DOE Green Energy (OSTI)

This final technical report describes work performed at Morehouse College under DOE Grant No. DE-FC26-04NT42130 during the period July 01, 2004 to June 30, 2007 which covers the entire performance period of the project. 25 individual biomass particles (hardwood sawdust AI14546 in the size range of 100-200 microns) were levitated in an electrodynamic balance (EDB) and their external surface area, volume, and drag coefficient/mass (C{sub d}/m) ratios were characterized applying highly specialized video based and high-speed diode array imaging systems. Analysis methods were employed using shape and drag information to calculate mass and density distributions for these particles. Results of these measurements and analyses were validated by independent mass measurements using a particle weighing and counting technique. Similar information for 28 PSOC 1451D bituminous coal particles was retrieved from a previously published work. Using these two information, density correlations for coal/biomass blends were developed. These correlations can be used to estimate the density of the blend knowing either the volume fraction or the mass fraction of coal in the blend. The density correlations presented here will be useful in predicting the burning rate of coal/biomass blends in cofiring combustors. Finally, a discussion on technological impacts and economic projections of burning biomass with coal in US power plants is presented.

Ramanathan Sampath

2007-06-30T23:59:59.000Z

208

Sources of Errors in Rainfall Measurements by Polarimetric Radar: Variability of Drop Size Distributions, Observational Noise, and Variation of Relationships between R and Polarimetric Parameters  

Science Conference Proceedings (OSTI)

Using a set of long-term disdrometric data and of actual radar measurements from the McGill S-band operational polarimetric radar, several sources of errors in rain measurement with polarimetric radar are explored in order to investigate their ...

Gyu Won Lee

2006-08-01T23:59:59.000Z

209

Statistics of Drop Size Distribution parameters and rain rates for Stratiform and Convective precipitation during the North-Australian wet season  

Science Conference Proceedings (OSTI)

C-band polarimetric radar measurements spanning two wet seasons are used to study the effects of the large-scale environment on the statistical properties of stratiform and convective rainfall around Darwin, Australia. The rainfall physical ...

Guillaume Penide; Vickal V. Kumar; Alain Protat; Peter T. May

210

Impacts of Venturi Turbulent Mixing on the Size Distributions of Sodium Chloride and Dioctyl-Phthalate Aerosols  

DOE Green Energy (OSTI)

Internal combustion engines are a major source of airborne particulate matter (PM). The size of the engine PM is in the sub-micrometer range. The number of engine particles per unit volume is high, normally in the range of 10{sup 12} to 10{sup 14}. To measure the size distribution of the engine particles dilution of an aerosol sample is required. A diluter utilizing a venturi ejector mixing technique is commercially available and tested. The purpose of this investigation was to determine if turbulence created by the ejector in the mini-dilutor changes the size of particles passing through it. The results of the NaCl aerosol experiments show no discernible difference in the geometric mean diameter and geometric standard deviation of particles passing through the ejector. Similar results were found for the DOP particles. The ratio of the total number concentrations before and after the ejector indicates that a dilution ratio of approximately 20 applies equally for DOP and NaCl particles. This indicates the dilution capability of the ejector is not affected by the particle composition. The statistical analysis results of the first and second moments of a distribution indicate that the ejector may not change the major parameters (e.g., the geometric mean diameter and geometric standard deviation) characterizing the size distributions of NaCl and DOP particles. However, when the skewness was examined, it indicates that the ejector modifies the particle size distribution significantly. The ejector could change the skewness of the distribution in an unpredictable and inconsistent manner. Furthermore, when the variability of particle counts in individual size ranges as a result of the ejector is examined, one finds that the variability is greater for DOP particles in the size range of 40-150 nm than for NaCl particles in the size range of 30 to 350 nm. The numbers or particle counts in this size region are high enough that the Poisson counting errors are small (<10%) compared with the tail regions. This result shows that the ejector device could have a higher bin-to-bin counting uncertainty for ''soft'' particles such as DOP than for a solid dry particle like NaCl. The results suggest that it may be difficult to precisely characterize the size distribution of particles ejected from the mini-dilution system if the particle is not solid.

Cheng, M-D.

2000-08-23T23:59:59.000Z

211

Impacts of Venturi Turbulent Mixing on the Size Distribution of Sodium Chloride and Dioctyl-Phthalate Aerosols  

DOE Green Energy (OSTI)

Internal combustion engines are a major source of airborne particulate matter (PM). The size of the engine PM is in the sub-micrometer range. The number of engine particles per unit volume is high, normally in the range of 10{sup 12} to 10{sup 14}. To measure the size distribution of the engine particles dilution of an aerosol sample is required. A diluter utilizing a venturi ejector mixing technique is commercially available and tested. The purpose of this investigation was to determine if turbulence created by the ejector in the mini-dilutor changes the size of particles passing through it.

Cheng, M.-D.; Wainman, T.; Storey, J.

2000-08-01T23:59:59.000Z

212

Residual carbon from pulverized coal fired boilers 1: Size distribution and combustion reactivity  

Science Conference Proceedings (OSTI)

The amount of residual, or unburned, carbon in fly ash is an important concern in the design and operation of pulverized coal-fired boilers. Char oxidation is the slowest step in the coal combustion process, and the rate at which this heterogeneous reaction-proceeds has an important effect on the degree of carbon burnout. There is an extensive literature on char combustion kinetics based on data in the early and intermediate stages of carbon conversion. A critical fundamental question is whether the small fraction of the fuel carbon that passes unreacted through a boiler is representative of the char during the main portion of the combustion process. This article addresses that question through a detailed characterization of eight carbon-containing fly ash samples acquired from commercial-scale combustion systems. The fly ash characterization included measurement-of joint carbon/size distribution and determination.of the combustion reactivity of the residual carbon. To minimize mineral matter interactions in the reactivity tests, the technique of incipient fluidization was developed for separation of carbon-rich extracts from the inorganic portion of the fly ash. Reactivity measurements were made at 1400--1800 K to represent conditions in pulverized coal fired boilers. Measurements were also made at 700--1100 K to. minimize transport effects and isolate the influence of char chemistry and microstructure. In both temperature regimes, the residual carbon extracts. were significantly less reactive than chars extracted from a laboratory-scale laminar flow reactor in the early-to-intermediate stages of combustion. It is concluded that the boiler environment deactivates chars, making high carbon burnout more difficult to achieve than is predicted by existing char combustion kinetic models that were developed from data on the laboratory chars. Finally, the results are used to discuss potential char deactivation mechanisms, both thermal and oxidative, in coal-fired boilers.

Hurt, R.H. [Sandia National Labs., Livermore, CA (United States); Gibbins, J.R. [Imperial Coll. of Science, Technology and Medicine, London (United Kingdom). Dept. of Mechanical Engineering

1994-08-01T23:59:59.000Z

213

The Relation between the Area-Average Rain Rate and the Rain Cell Size Distribution Parameters  

Science Conference Proceedings (OSTI)

A review of the literature on the rain cell diameter distribution (RCDD) is first presented. It shows that RCDD, for a given rain-rate threshold ?, is accurately described by an exponential distribution with an exponential parameter ? weakly ...

Henri Sauvageot; Frédéric Mesnard; Ricardo S. Tenório

1999-01-01T23:59:59.000Z

214

Aerosol Particle Size Distribution (0.1–1.0 ?m) during the Chinooks of 1979 over Calgary, Canada  

Science Conference Proceedings (OSTI)

During the winter months of 1979, an Active Scattering Aerosol Spectrometer was operated in down-town Calgary to measure the effect of chinooks on the aerosol particle size distribution in the range 0.1–1.0 ?m. An Aerovironment Acoustic Sounder ...

C. V. Mathai; A. W. Harrison; T. Mathews

1980-05-01T23:59:59.000Z

215

Sieveless particle size distribution analysis of particulate materials through computer vision  

DOE Green Energy (OSTI)

This paper explores the inconsistency of length-based separation by mechanical sieving of particulate materials with standard sieves, which is the standard method of particle size distribution (PSD) analysis. We observed inconsistencies of length-based separation of particles using standard sieves with manual measurements, which showed deviations of 17 22 times. In addition, we have demonstrated the falling through effect of particles cannot be avoided irrespective of the wall thickness of the sieve. We proposed and utilized a computer vision with image processing as an alternative approach; wherein a user-coded Java ImageJ plugin was developed to evaluate PSD based on length of particles. A regular flatbed scanner acquired digital images of particulate material. The plugin determines particles lengths from Feret's diameter and width from pixel-march method, or minor axis, or the minimum dimension of bounding rectangle utilizing the digital images after assessing the particles area and shape (convex or nonconvex). The plugin also included the determination of several significant dimensions and PSD parameters. Test samples utilized were ground biomass obtained from the first thinning and mature stand of southern pine forest residues, oak hard wood, switchgrass, elephant grass, giant miscanthus, wheat straw, as well as Basmati rice. A sieveless PSD analysis method utilized the true separation of all particles into groups based on their distinct length (419 639 particles based on samples studied), with each group truly represented by their exact length. This approach ensured length-based separation without the inconsistencies observed with mechanical sieving. Image based sieve simulation (developed separately) indicated a significant effect (P < 0.05) on number of sieves used in PSD analysis, especially with non-uniform material such as ground biomass, and more than 50 equally spaced sieves were required to match the sieveless all distinct particles PSD analysis. Results substantiate that mechanical sieving, owing to handling limitations and inconsistent length-based separation of particles, is inadequate in determining the PSD of non-uniform particulate samples. The developed computer vision sieveless PSD analysis approach has the potential to replace the standard mechanical sieving. The plugin can be readily extended to model (e.g., Rosin Rammler) the PSD of materials, and mass-based analysis, while providing several advantages such as accuracy, speed, low cost, automated analysis, and reproducible results.

Igathinathane, C. [Mississippi State University (MSU); Pordesimo, L. O. [Mississippi State University (MSU); Columbus, Eugene P [ORNL; Batchelor, William D [ORNL; Sokhansanj, Shahabaddine [ORNL

2009-05-01T23:59:59.000Z

216

Modifying Char Dustcake Pressure Drop Using Particulate Additives  

DOE Green Energy (OSTI)

Coal gasification produces residual particles of coal char, coal ash, and sorbent that are suspended in the fuel gas stream exiting the gasifier. In most cases, these particles (referred to, hereafter, simply as char) must be removed from the stream prior to sending the gas to a turbine, fuel cell, or other downstream device. Currently, the most common approach to cleaning the gas stream at high temperature and pressure is by filtering the particulate with a porous ceramic or metal filter. However, because these dusts frequently have small size distributions, irregular morphology, and high specific surface areas, they can have very high gas flow resistance resulting in hot-gas filter system operating problems. Typical of gasification chars, the hot-gas filter dustcakes produced at the Power Systems Development Facility (PSDF) during recent coal gasification tests have had very high flow resistance (Martin et al, 2002). The filter system has been able to successfully operate, but pressure drops have been high and filter cleaning must occur very frequently. In anticipation of this problem, a study was conducted to investigate ways of reducing dustcake pressure drop. This paper will discuss the efficacy of adding low-flow-resistance particulate matter to the high-flow-resistance char dustcake to reduce dustcake pressure drop. The study had two parts: a laboratory screening study and confirming field measurements at the PSDF.

Landham, C.; Dahlin, R.S.; Martin, R.A.; Guan, X.

2002-09-19T23:59:59.000Z

217

A Three Parameter Representation of the Shape and Size Distributions of Hailstones—A Case Study  

Science Conference Proceedings (OSTI)

The characteristics of shapes and sizes of a sample of 679 hailstones, collected on 22 June 1976 during a hailstorm at Grover, Colorado, were analyzed using a three-parameter formula developed by us previously. These parameters are a, the ...

Pao K. Wang; Thomas J. Greenwald; Jianlu Wang

1987-04-01T23:59:59.000Z

218

Impact of Precipitation on Aerosol Spectral Optical Depth and Retrieved Size Distributions: A Case Study  

Science Conference Proceedings (OSTI)

A case study is presented on the impact of two isolated, strong thundershowers during a prevailing dry, sunny season on the spectral optical depths and inferred columnar size characteristics of atmospheric aerosols at a tropical station. Results ...

Auromeet Saha; K. Krishna Moorthy

2004-06-01T23:59:59.000Z

219

Effects of Variable Droplet Growth Histories on Droplet Size Distributions. Part I: Theory  

Science Conference Proceedings (OSTI)

A theoretical framework is developed that permits estimation of the effects of fluctuating supersaturation on the development of cloud droplet size spectra. The studies focus on the role of turbulent fluctuations in vertical wind and in the ...

William A. Cooper

1989-05-01T23:59:59.000Z

220

A Study of Cirrus Ice Particle Size Distribution Using TC4 Observations  

Science Conference Proceedings (OSTI)

An analysis of two days of in situ observations of ice particle size spectra, in convectively generated cirrus, obtained during NASA’s Tropical Composition, Cloud, and Climate Coupling (TC4) mission is presented. The observed spectra are examined ...

Lin Tian; Gerald M. Heymsfield; Lihua Li; Andrew J. Heymsfield; Aaron Bansemer; Cynthia H. Twohy; Ramesh C. Srivastava

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Method and apparatus for controlled size distribution of gel microspheres formed from aqueous dispersions  

DOE Patents (OSTI)

The present invention is directed to a method and apparatus for making a population of dense, closely size-controlled microspheres by sol-gel procedures wherein said microspheres are characterized by a significant percentage of said population being within a predetermined, relatively narrow size range. Microsphere populations thus provided are useful in vibratory-packed processes for nuclear fuels to be irradiated in LWR- and FBR-type nuclear reactors.

Ryon, Allen D. (Oak Ridge, TN); Haas, Paul A. (Knoxville, TN); Vavruska, John S. (Santa Fe, NM)

1984-01-01T23:59:59.000Z

222

Optimal Placement and Sizing of Distributed Generator Units using Genetic Optimization  

E-Print Network (OSTI)

and electricity in the distribution grid. A group of DG units can form a virtual power plant, being centrally of distributed generation units in a residential distri- bution grid. Power losses are minimized while grid topology with pro- duction and residential load data based on measurements. Different scenarios

223

KNIFE MILL COMMINUTION ENERGY ANALYSIS OF SWITCHGRASS, WHEAT STRAW, AND CORN STOVER AND CHARACTERIZATION OF PARTICLE SIZE DISTRIBUTIONS  

Science Conference Proceedings (OSTI)

Biomass preprocessing and pretreatment technologies such as size reduction and chemical preconditioning are aimed at reducing the cost of ethanol production from lignocellulosic biomass. Size reduction is an energy-intensive biomass preprocessing unit operation. In this study, switchgrass, wheat straw, and corn stover were chopped in an instrumented knife mill to evaluate size reduction energy and corresponding particle size distribution as determined with a standard forage sieve analyzer. Direct mechanical power inputs were determined using a dedicated data acquisition system for knife mill screen openings from 12.7 to 50.8 mm, rotor speeds between 250 and 500 rpm, and mass feed rates from 1 to 11 kg/min. A speed of 250 rpm gave optimum performance of the mill. Optimum feed rates for 25.4 mm screen and 250 rpm were 7.6, 5.8, and 4.5 kg/min for switchgrass, wheat straw, and corn stover, respectively. Total specific energy (MJ/Mg) was defined as the size reduction energy required to operate the knife mill plus that imparted to the biomass. Effective specific energy was defined as the energy imparted to the biomass. For these conditions, total specific energies were 27.3, 37.9, and 31.9 MJ/Mg and effective specific energies were 10.1, 15.5, and 3.2 MJ/Mg for switchgrass, wheat straw, and corn stover, respectively. These results demonstrated that biomass selection affects the size reduction energy, even for biomass with similar features. Second-order polynomial equations for the total specific energy requirement fitted well (R2 > 0.95) as a function of knife mill screen size, mass feed rate, and speed for biomass materials tested. The Rosin-Rammler equation fitted the cumulative undersize mass of switchgrass, wheat straw, and corn stover chop passed through ASABE sieves with high R2 (>0.983). Knife mill chopping of switchgrass, wheat straw, and corn stover resulted in particle size distributions classified as 'well-graded strongly fine-skewed mesokurtic', 'well-graded fine-skewed mesokurtic', and 'well-graded fine-skewed mesokurtic', respectively, for small knife mill screen sizes (12.7 to 25.4 mm) and distributions classified as 'well-graded fine-skewed mesokurtic', 'well-graded strongly fine-skewed mesokurtic', and 'well-graded fine-skewed mesokurtic', respectively, for the large screen size (50.8 mm). Total and effective specific energy values per unit size reduction of wheat straw were greater compared to those for switchgrass. Corn stover resulted in reduced total and effective specific energy per unit size reduction compared to wheat straw for the same operating conditions, but higher total specific energy per unit size reduction and lesser effective specific energy per unit size reduction compared to switchgrass. Data on minimized total specific energy with corresponding particle spectra will be useful for preparing feed material with a knife mill for subsequent grinding with finer size reduction devices.

Bitra, V.S.P. [University of Tennessee, Knoxville (UTK); Womac, A.R. [University of Tennessee, Knoxville (UTK); Sokhansanj, Shahabaddine [ORNL; Igathinathane, C. [North Dakota State University

2010-01-01T23:59:59.000Z

224

Refractive Index and Size Distribution of Aerosols as Estimated from Light Scattering Measurements  

Science Conference Proceedings (OSTI)

Angular distributions of the intensity of light scattered by airborne particles were measured for both parallel and perpendicularly polarized components. A precision polar nephelometer was constructed for use of this study. The data were analyzed ...

Masayuki Tanaka; Tamio Takamura; Teruyuki Nakajima

1983-07-01T23:59:59.000Z

225

Marine particle dynamics : sinking velocities, size distributions, fluxes, and microbial degradation rates  

E-Print Network (OSTI)

The sinking flux of particulate matter into the ocean interior is an oceanographic phenomenon that fuels much of the metabolic demand of the subsurface ocean and affects the distribution of carbon and other elements ...

McDonnell, Andrew M. P

2011-01-01T23:59:59.000Z

226

Laboratory Measurements of Particle Capture by Evaporating Cloud Drops  

Science Conference Proceedings (OSTI)

The capture efficiencies of evaporating cloud drops (56–93 ?m radius) for particles of manganese hypophosphite (0.58–3.2 ?m radius) were obtained experimentally. In each experimental run, a large number of widely spaced uniform size drops fell ...

K. H. Leong; K. V. Beard; Harry T. Ochs III

1982-05-01T23:59:59.000Z

227

Method and apparatus for controlled size distribution of gel microspheres formed from aqueous dispersions. [Patent application  

DOE Patents (OSTI)

The present invention is directed to a method and apparatus for making a population of dense, closely size-controlled microspheres by sol-gel procedures wherein said microspheres are characterized by a significant percentage of said population being within a predetermined, relatively narrow size range. This is accomplished by subjecting aqueous dispersions of a sol, within a water-immiscible organic liquid to a turbulent flow. Microsphere populations thus provided are useful in vibratory-packed processes for nuclear fuels to be irradiated in LWR- and FBR-type nuclear reactors.

Ryon, A.D.; Haas, P.A.; Vavruska, J.S.

1982-01-19T23:59:59.000Z

228

Control of emulsion drop production in flow focusing microfluidics  

E-Print Network (OSTI)

Generating droplets using flow-focusing microfluidics in multiphase flows has reached its limit that it cannot generate submicrometer droplets in size. Flow focusing geometry together with an electric field has been used to make smaller droplets in microchannels. The droplet size was controllable by the flow rate ratio as well as the electric field. The droplets size decreased as the voltage increased. A Taylor cone was formed to generate very fine droplets which were less than 1m? in diameter. The tip made smaller droplets due to the tangential force by the electric field. A small inner flow rate and high electric field were required to form a stable Taylor cone in a DC electric field. The droplet size, however, was not stable at a small water flow rate because the flow rate was not as accuate as required. When I used a modified syringe pump with more accurate flow rate control, I was able to obtain a stable set of data. A small change in droplet size occurred at low voltage. The drop size changed dramatically, when the voltage was high enough. I also observed how an AC electric field affects the droplet size. The droplet size was not solely determined by the voltage. This is because of the imbalance of the supplied flow rate and the emitted flow rate. I also found that the droplet size is related to the tip position of the dispersed phase. The droplet size decreased as the tip stretched more. Typically, the microfluidic device generated monodispese droplets in narrow size distribution. It also generated a bigger droplet followed by a smaller one consecutively at low flow rate ratio of inner and outer fluid flow ()265.0/09.0??oiQQ. To understand this instability of drop formation, a numerical calculation was conducted. The simulation results showed inside of the tip still pointed downstream after it generated a big droplet. Then, the tip generated another smaller droplet while the tip was stretched. Finally, the tip moved back and began a new cycle.

Kim, Haejune

2007-08-01T23:59:59.000Z

229

A New Look into the Treatment of Small-Scale Drop Variability...  

NLE Websites -- All DOE Office Websites (Extended Search)

entropy and thus convey minimum information about drop distribution variation in space (Ash 1965). The use of such distributions in the radiative transfer equation, therefore,...

230

Quantitative size-dependent structure and strain determination of CdSe nanoparticles using atomic pair distribution function analysis  

E-Print Network (OSTI)

The size-dependent structure of CdSe nanoparticles, with diameters ranging from 2 to 4 nm, has been studied using the atomic pair distribution function (PDF) method. The core structure of the measured CdSe nanoparticles can be described in terms of the wurtzite atomic structure with extensive stacking faults. The density of faults in the nanoparticles ~50% . The diameter of the core region was extracted directly from the PDF data and is in good agreement with the diameter obtained from standard characterization methods suggesting that there is little surface amorphous region. A compressive strain was measured in the Cd-Se bond length that increases with decreasing particle size being 0.5% with respect to bulk CdSe for the 2 nm diameter particles. This study demonstrates the size-dependent quantitative structural information that can be obtained even from very small nanoparticles using the PDF approach.

A. S. Masadeh; E. Bozin; C. L. Farrow; G. Paglia; P. Juhas; A. Karkamkar; M. G. Kanatzidis; S. J. L. Billinge

2007-04-10T23:59:59.000Z

231

An Inversion Problem on Inferring the Size Distribution of Precipitation Areas from Raingage Measurements  

Science Conference Proceedings (OSTI)

Given a long, continuous record of rain rate measured at a point on the ground, it is straightforward to select a threshold value of rate and note the duration of each event in which the threshold is exceeded. The distribution of durations for ...

M. K. Yau; R. R. Rogers

1984-02-01T23:59:59.000Z

232

Quantitative discrimination between geological materials with variable density contrast by high resolution X-ray computed tomography: An example using amygdule size-distribution in ancient lava flows  

Science Conference Proceedings (OSTI)

The bubble-size distribution in 2.7 billion year old lava flows can be used as a proof of concept illustrating a new set of techniques for measuring volumes of geological materials with variable density contrasts using high-resolution X-ray computed ... Keywords: Amygdules, Bootstrap resampling, Bubble-size distribution, Central limit theorem, Dynamic thresholding, X-ray tomography

Sanjoy M. Som, James W. Hagadorn, Weston A. Thelen, Alan R. Gillespie, David C. Catling, Roger Buick

2013-04-01T23:59:59.000Z

233

Critical error rate of quantum-key-distribution protocols versus the size and dimensionality of the quantum alphabet  

SciTech Connect

A quantum-information analysis of how the size and dimensionality of the quantum alphabet affect the critical error rate of the quantum-key-distribution (QKD) protocols is given on an example of two QKD protocols--the six-state and {infinity}-state (i.e., a protocol with continuous alphabet) ones. In the case of a two-dimensional Hilbert space, it is shown that, under certain assumptions, increasing the number of letters in the quantum alphabet up to infinity slightly increases the critical error rate. Increasing additionally the dimensionality of the Hilbert space leads to a further increase in the critical error rate.

Sych, Denis V.; Grishanin, Boris A.; Zadkov, Victor N. [International Laser Center and Faculty of Physics, M.V. Lomonosov Moscow State University, 119899 Moscow (Russian Federation)

2004-11-01T23:59:59.000Z

234

Catalytic reforming catalyst with modified pore size distribution and a process using the same  

Science Conference Proceedings (OSTI)

This patent describes a catalytic reforming process for conversion of a naptha hydrocarbon at reforming conditions using a catalyst comprising at least one catalytic metal and alumina. The improvement comprises using a catalyst having the following properties in combination: a surface area above about 250 M/sup 2//gram of catalyst; a pore volume above about 0.44 cc/gram of catalyst in pores having diameters of from about 30 angstroms to about 38,000 angstroms; and a pore volume distribution wherein about 70 percent or less of the pore volume is in pores having diameters of from about 30 angstroms to about 400 angstroms. About 30 percent or more pore volume is in pores having diameters of from about 400 angstroms to about 38,000 angstroms.

Unmuth, E.E.; Fleming, B.A.

1987-05-12T23:59:59.000Z

235

First drop dissimilarity in drop-on-demand inkjet devices  

SciTech Connect

As inkjet printing technology is increasingly applied in a broader array of applications, careful characterization of its method of use is critical due to its inherent sensitivity. A common operational mode in inkjet technology known as drop-on-demand ejection is used as a way to deliver a controlled quantity of material to a precise location on a target. This method of operation allows ejection of individual or a sequence (burst) of drops based on a timed trigger event. This work presents an examination of sequences of drops as they are ejected, indicating a number of phenomena that must be considered when designing a drop-on-demand inkjet system. These phenomena appear to be driven by differences between the first ejected drop in a burst and those that follow it and result in a break-down of the linear relationship expected between driving amplitude and drop mass. This first drop, as quantified by high-speed videography and subsequent image analysis, can be different in morphology, trajectory, velocity, and volume from subsequent drops within a burst. These findings were confirmed orthogonally by both volume and mass measurement techniques which allowed quantitation down to single drops.

Famili, Amin; Palkar, Saurabh A.; Baldy, William J. Jr. [Cordis Corporation, a Johnson and Johnson Company, Welsh and McKean Roads, Spring House, Pennsylvania 19477 (United States)

2011-01-15T23:59:59.000Z

236

The Impact of Oil Consumption Mechanisms on Diesel Exhaust Particle Size Distributions and Detailed Exhaust Chemical Composition  

DOE Green Energy (OSTI)

Detailed exhaust emission data have been taken from a Cummins N-14 single cylinder research engine in which the oil consumption was varied by different engine modifications. Low sulfur fuel was used, and oil consumption was varied by modifying the intake valve stem seals, the exhaust valve stem seals, the oil control ring and combinations of these modifications. Detailed measurements of exhaust gas particle size distributions and chemical composition were made for the various oil consumption configurations for a range of engine loads and speeds. The particulate mass was measured with TEOM and traditional gravimetric filter methods. Filter data for EC/OC, sulfates and trace metals have been taken and analyzed. The trace metals in the particulate mass serve as the basis for assessing oil consumption at the different operating conditions. The data indicate that the oil consumption for the steady state testing done here was approximately an order of magnitude below oil consumption values cited in the literature. We did measure changes in the details of the chemical composition of the particulate for the different engine operating conditions, but it did not correlate with changes in the oil consumption. Furthermore, the data indicate that the particle size distribution is not strongly impacted by low level oil consumption variations observed in this work.

Stetter, J; Forster, N; Ghandhi, J; Foster, D

2003-08-24T23:59:59.000Z

237

Electrical Mobility Spectrometer Using a Diethylene Glycol Condensation Particle Counter for Measurement of Aerosol Size Distributions Down to 1 nm  

Science Conference Proceedings (OSTI)

We report a new scanning mobility particle spectrometer (SMPS) for measuring number size distributions of particles down to {approx}1 nm mobility diameter. This SMPS includes an aerosol charger, a TSI 3085 nano differential mobility analyzer (nanoDMA), an ultrafine condensation particle counter (UCPC) using diethylene glycol (DEG) as the working fluid, and a conventional butanol CPC (the 'booster') to detect the small droplets leaving the DEG UCPC. The response of the DEG UCPC to negatively charged sodium chloride particles with mobility diameters ranging from 1-6 nm was measured. The sensitivity of the DEG UCPC to particle composition was also studied by comparing its response to positively charged 1.47 and 1.70 nm tetra-alkyl ammonium ions, sodium chloride, and silver particles. A high resolution differential mobility analyzer was used to generate the test particles. These results show that the response of this UCPC to sub-2 nm particles is sensitive to particle composition. The applicability of the new SMPS for atmospheric measurement was demonstrated during the Nucleation and Cloud Condensation Nuclei (NCCN) field campaign (Atlanta, Georgia, summer 2009). We operated the instrument at saturator and condenser temperatures that allowed the efficient detection of sodium chloride particles but not of air ions having the same mobility. We found that particles as small as 1 nm were detected during nucleation events but not at other times. Factors affecting size distribution measurements, including aerosol charging in the 1-10 nm size range, are discussed. For the charger used in this study, bipolar charging was found to be more effective for sub-2 nm particles than unipolar charging. No ion induced nucleation inside the charger was observed during the NCCN campaign.

Jiang, J.; Kuang, C.; Chen, M.; Attoui, M.; McMurry, P. H.

2011-02-01T23:59:59.000Z

238

Fundamental Drop Dynamics and Mass Transfer Experiments to Support Solvent Extraction Modeling Efforts  

SciTech Connect

In support of the Nuclear Energy Advanced Modeling Simulation Safeguards and Separations (NEAMS SafeSep) program, the Idaho National Laboratory (INL) worked in collaboration with Los Alamos National Laboratory (LANL) to further a modeling effort designed to predict mass transfer behavior for selected metal species between individual dispersed drops and a continuous phase in a two phase liquid-liquid extraction (LLE) system. The purpose of the model is to understand the fundamental processes of mass transfer that occur at the drop interface. This fundamental understanding can be extended to support modeling of larger LLE equipment such as mixer settlers, pulse columns, and centrifugal contactors. The work performed at the INL involved gathering the necessary experimental data to support the modeling effort. A custom experimental apparatus was designed and built for performing drop contact experiments to measure mass transfer coefficients as a function of contact time. A high speed digital camera was used in conjunction with the apparatus to measure size, shape, and velocity of the drops. In addition to drop data, the physical properties of the experimental fluids were measured to be used as input data for the model. Physical properties measurements included density, viscosity, surface tension and interfacial tension. Additionally, self diffusion coefficients for the selected metal species in each experimental solution were measured, and the distribution coefficient for the metal partitioning between phases was determined. At the completion of this work, the INL has determined the mass transfer coefficient and a velocity profile for drops rising by buoyancy through a continuous medium under a specific set of experimental conditions. Additionally, a complete set of experimentally determined fluid properties has been obtained. All data will be provided to LANL to support the modeling effort.

Kristi Christensen; Veronica Rutledge; Troy Garn

2011-09-01T23:59:59.000Z

239

Chemoembolization Decreases Drop-Off Risk of Hepatocellular Carcinoma Patients on the Liver Transplant List  

Science Conference Proceedings (OSTI)

Introduction: The drop-off risk for patients awaiting liver transplantation for hepatocellular carcinoma (HCC) is 22%. Transplant liver availability is expected to worsen, resulting in longer waiting times and increased drop-off rates. Our aim was to determine whether chemoembolization can decrease this risk. Patients and Methods: Eighty-seven consecutive HCC patients listed for liver transplant (Milan criteria) underwent statistical comparability adjustments using the propensity score (Wilcoxon, Fisher's, and chi-square tests). Forty-three nonchemoembolization patients and 22 chemoembolization patients were comparable for Child-Pugh and Model for End-Stage Liver Disease scores, tumor size and number, alpha fetoprotein (AFP) levels, and cause of cirrhosis. We calculated the risk of dropping off the transplant list by assigning a transplant time to those who dropped off (equal probability with patients who were on the list longer than the patient in question). The significance level was obtained by calculating the simulation distribution of the difference compared with the permutations of chemoembolization versus nonchemoembolization assignment of the patients. Kaplan-Meier estimators (log-rank test) were used to determine survival rates. Results: Median follow-up was 187 {+-} 110 weeks (range 38 to 435, date of diagnosis). The chemoembolization group had an 80% drop-off risk decrease (15% nonchemoembolization versus 3% chemoembolization, p = 0.04). Although survival was better for the chemoembolization group, it did not reach statistical significance. Two-year survival for the nonchemoembolization and chemoembolization group was 57.3% {+-} 7.1% and 76.0% {+-} 7.9%, respectively (p = 0.078). Conclusions: Chemoembolization appears to result in a significant decrease in the risk of dropping off liver transplant list for patients with HCC and results in a tendency toward longer survival.

Frangakis, Constantine [Johns Hopkins University, Department of Biostatistics, Bloomberg School of Public Health (United States); Geschwind, Jean-Francois; Kim, Daniel [Johns Hopkins University, Department of Vascular and Interventional Radiology (United States); Chen, Yong [Johns Hopkins University, Department of Biostatistics, Bloomberg School of Public Health (United States); Koteish, Ayman [Johns Hopkins University, Department of Transplant Hepatology (United States); Hong, Kelvin; Liapi, Eleni; Georgiades, Christos S., E-mail: g_christos@hotmail.com [Johns Hopkins University, Department of Vascular and Interventional Radiology (United States)

2011-12-15T23:59:59.000Z

240

Aerosol Size Distribution, Particle Concentration, and Optical Property Variability near Caribbean Trade Cumulus Clouds: Isolating Effects of Vertical Transport and Cloud Processing from Humidification Using Aircraft Measurements  

Science Conference Proceedings (OSTI)

This paper examines the effect of trade wind cumulus clouds on aerosol properties in the near-cloud environment using data from the Rain in Cumulus over the Ocean (RICO) campaign. Aerosol size distributions, particle concentrations, and optical ...

Robert M. Rauber; Guangyu Zhao; Larry Di Girolamo; Marilé Colón-Robles

2013-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Diurnal Variations and Modulation by Easterly Waves of the Size Distribution of Convective Cloud Clusters over West Africa and the Atlantic Ocean  

Science Conference Proceedings (OSTI)

Using Metecosat satellite data in the atmospheric infrared window, the authors study short time-scale fluctuations of the size distribution of tropical convective cloud clusters for July to September 1989. A cluster at a given brightness-...

L. A. Toledo Machado; J-Ph Duvel; M. Desbois

1993-01-01T23:59:59.000Z

242

Determining Size Distributions and Composition of Particles Suspended in Water: A New SEM–EDS Protocol with Validation and Comparison to Other Methods  

Science Conference Proceedings (OSTI)

Knowledge of particle size distributions (PSDs) in seawater is important for understanding several facets of marine science, such as the behavior of light scattering in seawater, phytoplankton dynamics, and biogeochemical cycling. Here, a method ...

Heather Groundwater; Michael S. Twardowski; Heidi M. Dierssen; Antoine Sciandra; Scott A. Freeman

2012-03-01T23:59:59.000Z

243

Particles in the Lower Troposphere over the High Plains of the United States. Part I: Size Distributions, Elemental Compositions and Morphologies  

Science Conference Proceedings (OSTI)

Airborne measurements are presented of particle size distributions obtained during spring and summer at various locations in the High Plains of the United States. Two main particle modes are apparent: an accumulation mode between particle ...

Peter V. Hobbs; David A. Bowdle; Lawrence F. Radke

1985-12-01T23:59:59.000Z

244

Estimation of N*0 for the Two-Scale Gamma Raindrop Size Distribution Model and Its Statistical Properties at Several Locations in Asia  

Science Conference Proceedings (OSTI)

An automatic estimation method is developed to detect stepwise changes in the amplitude parameter of the normalized raindrop size distribution (DSD) N*0. To estimate N*0, it is also assumed that the variation of three DSD parameters follows the ...

Toshiaki Kozu; Kazuhiro Masuzawa; Toyoshi Shimomai; Nobuhisa Kashiwagi

2010-04-01T23:59:59.000Z

245

Comparison of Raindrop Size Distribution Measurements by a Joss-Waldvogel Disdrometer, a PMS 2DG Spectrometer, and a POSS Doppler Radar  

Science Conference Proceedings (OSTI)

Three techniques for the measurement of raindrop size distributions are compared using data from a Joss-Waldvogel disdrometer (JWD), a Particle Measuring Systems 2DG spectrometer (PMS), and an Atmospheric Environment Service (AES) Precipitation ...

B. E. Sheppard; P. I. Joe

1994-08-01T23:59:59.000Z

246

Hydrated and Dried Aerosol-Size-Distribution Measurements from the Particle Measuring Systems FSSP-300 Probe and the Deiced PCASP-100X Probe  

Science Conference Proceedings (OSTI)

Comparisons of particle-size distributions measured by Particle Measuring Systems FSSP-300 and PCASP-100X probes through a range of relative humidities reveal that the deiced PCASP-100X probe dries hydrated submicron aerosols before measurement. ...

J. Walter Strapp; W. R. Leaitch; P. S. K. Liu

1992-10-01T23:59:59.000Z

247

Leakage diagnostics, sealant longevity, sizing and technologytransfer in residential thermal distribution systems: Part II.Residential thermal Distribution Systesm, Phase VI FinalReport  

SciTech Connect

This report builds on and extends our previous efforts as described in "Leakage Diagnostics, Sealant Longevity, Sizing and Technology Transfer in Residential Thermal Distribution Systems- CIEE Residential Thermal Distribution Systems Phase V Final Report, October 1997". New developments include defining combined duct and equipment efficiencies in a concept called "Tons At the Register" and on performance issues related to field use of the aerosol sealant technology. Some of the key results discussed in this report include: o Register, boot and air handler cabinet leakage can often represent a significant fraction of the total duct leakage in new construction. Because of the large range of pressures in duct systems an accurate characterization may require separating these components through improved leakage testing. o Conventional duct tape failed our accelerated longevity testing and is not, therefore, considered generally acceptable for use in sealing duct systems. Many other tapes and sealing approaches are available and practical and have passed our longevity tests. o Simulations of summer temperature pull-down time have shown that duct system improvements can be combined with equipment downsizing to save first cost, energy consumption, and peak power and still provide equivalent or superior comfort. o Air conditioner name plate capacity ratings alone are a poor indicator of how much cooling will actually be delivered to the conditioned space. Duct system efficiency can have as large an impact on performance as variations in SEER. o Mechanical duct cleaning techniques do not have an adverse impact on the ducts sealed with the Aerosol sealant. The material typically used in Aerosol sealing techniques does not appear to present a health or safety hazard. Results from this study were used by the California Energy Commission in the formation of the current Energy Efficiency Standards for Low-Rise Residential Buildings (CEC, (1998)), often referred to as Title 24. Current information on ducts and thermal distribution research can be found at http://ducts.lbl.gov

Buchanan, C.; Modera, M.; Sherman, M.; Siegel, J.; Walker, I.; Wang, D.

1998-12-01T23:59:59.000Z

248

Pressure Drops Due to Silica Scaling  

DOE Green Energy (OSTI)

Experience with reinjection returns in many geothermal fields has prompted a move towards injecting waste fluids at some distance from the production field. This means that often, reinjection pipelines cover very long distances. If the waste water in the pipelines is supersaturated with respect to amorphous silica, then the deposition of silica in these pipelines is almost certain. Although the deposit may be of negligible thickness, the inner surface characteristics of the pipe will be different to those of clean mild steel. During a silica scaling experiment. geothermal brine was passed through a series of pipes of different sizes and over a period of three weeks, silica scale formed on the inner surface. The pressure drop along a distance of approximately 5m was measured by a water manometer in all test pipe sections. Significant pressure drop was observed during this time and can be correlated with the increase in the friction factor of the pipe walls due to silica scaling.

Brown, K.L.; Freeston, D.H.; Dimas, Z.O.; Slatter, A.

1995-01-01T23:59:59.000Z

249

Diesel prices see slight drop  

U.S. Energy Information Administration (EIA) Indexed Site

Diesel prices see slight drop The U.S. average retail price for on-highway diesel fuel fell slightly to 3.91 a gallon on Monday. That's down 6-tenths of a penny from a week ago,...

250

Ultrasonic characterization of single drops of liquids  

DOE Patents (OSTI)

Ultrasonic characterization of single drops of liquids is disclosed. The present invention includes the use of two closely spaced transducers, or one transducer and a closely spaced reflector plate, to form an interferometer suitable for ultrasonic characterization of droplet-size and smaller samples without the need for a container. The droplet is held between the interferometer elements, whose distance apart may be adjusted, by surface tension. The surfaces of the interferometer elements may be readily cleansed by a stream of solvent followed by purified air when it is desired to change samples. A single drop of liquid is sufficient for high-quality measurement. Examples of samples which may be investigated using the apparatus and method of the present invention include biological specimens (tear drops; blood and other body fluid samples; samples from tumors, tissues, and organs; secretions from tissues and organs; snake and bee venom, etc.) for diagnostic evaluation, samples in forensic investigations, and detection of drugs in small quantities. 5 figs.

Sinha, D.N.

1998-04-14T23:59:59.000Z

251

Optimal Siting and Sizing of Solar Photovoltaic Distributed Generation to Minimize Loss, Present Value of Future Asset Upgrades and Peak Demand Costs on a Real Distribution Feeder.  

E-Print Network (OSTI)

??The increasing penetration of distributed generation (DG) in power distribution systems presents technical and economic benefits as well as integration challenges to utility engineers. Governments… (more)

Mukerji, Meghana

2011-01-01T23:59:59.000Z

252

Aerosol concentration and size distribution measured below, in, and above cloud from the DOE G-1 during VOCALS-REx  

SciTech Connect

During the VOCALS Regional Experiment, the DOE G-1 aircraft was used to sample a varying aerosol environment pertinent to properties of stratocumulus clouds over a longitude band extending 800 km west from the Chilean coast at Arica. Trace gas and aerosol measurements are presented as a function of longitude, altitude, and dew point in this study. Spatial distributions are consistent with an upper atmospheric source for O{sub 3} and South American coastal sources for marine boundary layer (MBL) CO and aerosol, most of which is acidic sulfate in agreement with the dominant pollution source being SO{sub 2} from Cu smelters and power plants. Pollutant layers in the free troposphere (FT) can be a result of emissions to the north in Peru or long range transport from the west. At a given altitude in the FT (up to 3 km), dew point varies by 40 C with dry air descending from the upper atmospheric and moist air having a BL contribution. Ascent of BL air to a cold high altitude results in the condensation and precipitation removal of all but a few percent of BL water along with aerosol that served as CCN. Thus, aerosol volume decreases with dew point in the FT. Aerosol size spectra have a bimodal structure in the MBL and an intermediate diameter unimodal distribution in the FT. Comparing cloud droplet number concentration (CDNC) and pre-cloud aerosol (Dp > 100 nm) gives a linear relation up to a number concentration of {approx}150 cm{sup -3}, followed by a less than proportional increase in CDNC at higher aerosol number concentration. A number balance between below cloud aerosol and cloud droplets indicates that {approx}25% of aerosol in the PCASP size range are interstitial (not activated). One hundred and two constant altitude cloud transects were identified and used to determine properties of interstitial aerosol. One transect is examined in detail as a case study. Approximately 25 to 50% of aerosol with D{sub p} > 110 nm were not activated, the difference between the two approaches possibly representing shattered cloud droplets or unknown artifact. CDNC and interstitial aerosol were anti-correlated in all cloud transects, consistent with the occurrence of dry in-cloud areas due to entrainment or circulation mixing.

Kleinman, L.I.; Daum, P. H.; Lee, Y.-N.; Lewis, E. R.; Sedlacek III, A. J.; Senum, G. I.; Springston, S. R.; Wang, J.; Hubbe, J.; Jayne, J.; Min, Q.; Yum, S. S.; Allen, G.

2011-06-21T23:59:59.000Z

253

Stationary liquid drops in Lorentz-Minkowski space  

E-Print Network (OSTI)

This paper analyzes the configurations of shapes that shows a spacelike liquid drop in Minkowski space deposited over a spacelike plane $\\Pi$. We assume the presence of a uniform gravity field directed toward $\\Pi$ and that the volume of the drop is prescribed. Our interest are the liquid drops that are critical points of the energy of the corresponding mechanical system and we will say then that the liquid drop is stationary. In such case, the liquid-air interface is determined by the condition that the mean curvature is a linear function of distance from $\\Pi$ and that the drop makes a constant hyperbolic angle of contact with the plate $\\Pi$. As first result, we shall prove that the liquid drop must be rotational symmetric with respect to an axis orthogonal to $\\Pi$. Then we prove the existence and uniqueness of symmetric solutions for a given angle of contact with $\\Pi$. Finally, we shall study the shapes that a liquid drop can adopt in terms of its size. So, we shall derive estimates of its height, volume and area of the wetted surface on $\\Pi$.

Rafael Lopez

2005-01-12T23:59:59.000Z

254

The Occurrence of Particle Size Distribution Bimodality in Midlatitude Cirrus as Inferred from Ground-Based Remote Sensing Data  

SciTech Connect

To better understand the role of small particles in the microphysical processes and the radiative properties of cirrus, the reliability of historical in-situ data must be understood. Recent studies call into question the validity of that data because of shattering of large crystals on probe and aircraft surfaces thereby artificially amplifying the concentration of crystals smaller than approximately 50 ?m. We contend that the general character of the in-situ measurements must be consistent, in a broad sense, with statistics derived from long-term remote sensing data. To examine this consistency, an algorithm using Doppler radar moments and Raman lidar extinction is developed to retrieve a bimodal particle size distribution and its uncertainty. Using case studies and statistics compiled over one year we show that the existence of high concentrations (> 1 cm-3 ) of small (sub 50 ?m) particles in cirrus are not consistent with any reasonable interpretation of the remote sensing data. We conclude that the high concentrations of small particles found in many aircraft data sets are therefore likely an artifact of the in situ measurement process.

Zhao, Yang; Mace, Gerald G.; Comstock, Jennifer M.

2011-06-01T23:59:59.000Z

255

Aerosol concentration and size distribution measured below, in, and above cloud from the DOE G-1 during VOCALS-REx  

SciTech Connect

During the VOCALS Regional Experiment, the DOE G-1 aircraft was used to sample a varying aerosol environment pertinent to properties of stratocumulus clouds over a longitude band extending 800 km west from the Chilean coast at Arica. Trace gas and aerosol measurements are presented as a function of longitude, altitude, and dew point in this study. Spatial distributions are consistent with an upper atmospheric source for O{sub 3} and South American coastal sources for marine boundary layer (MBL) CO and aerosol, most of which is acidic sulfate. Pollutant layers in the free troposphere (FT) can be a result of emissions to the north in Peru or long range transport from the west. At a given altitude in the FT (up to 3 km), dew point varies by 40 C with dry air descending from the upper atmospheric and moist air having a boundary layer (BL) contribution. Ascent of BL air to a cold high altitude results in the condensation and precipitation removal of all but a few percent of BL water along with aerosol that served as CCN. Thus, aerosol volume decreases with dew point in the FT. Aerosol size spectra have a bimodal structure in the MBL and an intermediate diameter unimodal distribution in the FT. Comparing cloud droplet number concentration (CDNC) and pre-cloud aerosol (D{sub p} > 100 nm) gives a linear relation up to a number concentration of {approx}150 cm{sup -3}, followed by a less than proportional increase in CDNC at higher aerosol number concentration. A number balance between below cloud aerosol and cloud droplets indicates that {approx}25 % of aerosol with D{sub p} > 100 nm are interstitial (not activated). A direct comparison of pre-cloud and in-cloud aerosol yields a higher estimate. Artifacts in the measurement of interstitial aerosol due to droplet shatter and evaporation are discussed. Within each of 102 constant altitude cloud transects, CDNC and interstitial aerosol were anti-correlated. An examination of one cloud as a case study shows that the interstitial aerosol appears to have a background, upon which is superimposed a high frequency signal that contains the anti-correlation. The anti-correlation is a possible source of information on particle activation or evaporation.

Kleinman L. I.; Daum, P. H.; Lee, Y.-N.; Lewis, E. R.; Sedlacek III, A. J.; Senum, G. I.; Springston, S. R.; Wang, J.; Hubbe, J.; Jayne, J.; Min, Q.; Yum, S. S.; Allen, G.

2012-01-04T23:59:59.000Z

256

Direct mechanical energy measures of hammer mill comminution of switchgrass, wheat straw, and corn stover and analysis of their particle size distributions  

Science Conference Proceedings (OSTI)

Biomass particle size impacts handling, storage, conversion, and dust control systems. Size reduction mechanical energy was directly measured for switchgrass (Panicum virgatum L.), wheat straw (Triticum aestivum L.), and corn stover (Zea mays L.) in an instrumented hammer mill. Direct energy inputs were determined for hammer mill operating speeds from 2000 to 3600 rpm for 3.2 mm integral classifying screen and mass input rate of 2.5 kg/min with 90 - and 30 -hammers. Overall accuracy of specific energy measurement was calculated as 0.072 MJ/Mg. Particle size distributions created by hammer mill were determined for mill operating factors using ISO sieve sizes from 4.75 to 0.02 mm in conjunction with Ro-Tap sieve analyzer. A wide range of analytical descriptors were examined to mathematically represent the range of particle sizes in the distributions. Total specific energy (MJ/Mg) was defined as size reduction energy to operate the hammer mill plus that imparted to biomass. Effective specific energy was defined as energy imparted to biomass. Total specific energy for switchgrass, wheat straw, and corn stover grinding increased by 37, 30, and 45% from 114.4, 125.1, and 103.7 MJ/Mg, respectively, with an increase in hammer mill speed from 2000 to 3600 rpm for 90 -hammers. Corresponding total specific energy per unit size reduction was 14.9, 19.7, and 13.5 MJ/Mg mm, respectively. Effective specific energy of 90 -hammers decreased marginally for switchgrass and considerably for wheat straw and it increased for corn stover with an increase in speed from 2000 to 3600 rpm. However, effective specific energy increased with speed to a certain extent and then decreased for 30 -hammers. Rosin Rammler equation fitted the size distribution data with R2 > 0.995. Mass relative span was greater than 1, which indicated a wide distribution of particle sizes. Hammer milling of switchgrass, wheat straw, and corn stover with 3.2 mm screen resulted in well-graded fine-skewed mesokurtic particles. Uniformity coefficient was corn stover, which indicated a moderate assortment of particles. Size-related parameters, namely, geometric mean diameter, Rosin Rammler size parameter, median diameter, and effective size had strong correlation among themselves and good negative correlation with speed. Distribution-related parameters, namely, Rosin Rammler distribution parameter, mass relative span, inclusive graphic skewness, graphic kurtosis, uniformity index, uniformity coefficient, coefficient of gradation and distribution geometric standard deviation had strong correlation among themselves and a weak correlation with mill speed. Results of this extensive analysis of specific energy and particle sizes can be applied to selection of hammer mill operating factors to produce a particular size of switchgrass, wheat straw, and corn stover grind, and will serve as a guide for relations among the energy and various analytic descriptors of biomass particle distributions.

Bitra, V.S.P [University of Tennessee; Womac, A.R. [University of Tennessee; Chevanan, Nehru [University of Tennessee; Miu, P.I. [University of Tennessee; Smith, D.R. [University of Tennessee; Igathinathane, C. [Mississippi State University (MSU); Sokhansanj, Shahabaddine [ORNL

2009-07-01T23:59:59.000Z

257

Alpha spectrometric characterization of process-related particle size distributions from active particle sampling at the Los Alamos National Laboratory uranium foundry  

SciTech Connect

Uranium particles within the respirable size range pose a significant hazard to the health and safety of workers. Significant differences in the deposition and incorporation patterns of aerosols within the respirable range can be identified and integrated into sophisticated health physics models. Data characterizing the uranium particle size distribution resulting from specific foundry-related processes are needed. Using personal air sampling cascade impactors, particles collected from several foundry processes were sorted by activity median aerodynamic diameter onto various Marple substrates. After an initial gravimetric assessment of each impactor stage, the substrates were analyzed by alpha spectrometry to determine the uranium content of each stage. Alpha spectrometry provides rapid nondestructive isotopic data that can distinguish process uranium from natural sources and the degree of uranium contribution to the total accumulated particle load. In addition, the particle size bins utilized by the impactors provide adequate resolution to determine if a process particle size distribution is: lognormal, bimodal, or trimodal. Data on process uranium particle size values and distributions facilitate the development of more sophisticated and accurate models for internal dosimetry, resulting in an improved understanding of foundry worker health and safety.

Plionis, Alexander A [Los Alamos National Laboratory; Peterson, Dominic S [Los Alamos National Laboratory; Tandon, Lav [Los Alamos National Laboratory; Lamont, Stephen P [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

258

Unified formulation of single and multi-moment normalizations of the raindrop size distribution based on the gamma probability density function  

Science Conference Proceedings (OSTI)

This study offers a unified formulation of single and multi-moment normalizations of the raindrop size distribution (DSD), which have been proposed in the framework of scaling analyses in the literature. The key point is to consider a well-defined ...

Nan Yu; Guy Delrieu; Brice Boudevillain; Pieter Hazenberg; Remko Uijlenhoet

259

A Microcomputer Data-Acquisition System for Real-Time Processing of Raindrop Size Distribution Measured with the RD69 Distrometer  

Science Conference Proceedings (OSTI)

The disdrometer is an instrument used worldwide to measure the size distribution of raindrops at ground level. In this paper, a data-acquisition and real-time processing system designed for disdrometer measurements is presented. It is based on a ...

Bernard Campistron; Gilbert Despaux; Jean-Pierre Lacaux

1987-09-01T23:59:59.000Z

260

Simultaneous Measurements of Drop Size and Velocity in ...  

Science Conference Proceedings (OSTI)

... of entrained air velocity. An example is presented in Prahl and Wendt (1988) and Wendt and Prahl (1986) where the authors ...

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Simultaneous Measurements of Drop Size and Velocity in ...  

Science Conference Proceedings (OSTI)

... from the symmetric centerline of the orifice. The large orange circle is a light emitting diode used as a reference location. Page 53. Figure 50. ...

2003-08-28T23:59:59.000Z

262

The Impact of Ice Crystal Shapes, Size Distributions, and Spatial Structures of Cirrus Clouds on Solar Radiative Fluxes  

Science Conference Proceedings (OSTI)

The solar radiative properties of cirrus clouds depend on ice particle shape, size, and orientation, as well as on the spatial cloud structure. Radiation schemes in atmospheric circulation models rely on estimates of cloud optical thickness only. ...

I. Schlimme; A. Macke; J. Reichardt

2005-07-01T23:59:59.000Z

263

On the Aerosol Particle Size Distribution Spectrum in Alaskan Air Mass Systems: Arctic Haze and Non-Haze Episodes  

Science Conference Proceedings (OSTI)

Aerosols in central Alaskan winter air mass system were classified according to size by diffusive separation and light-scattering spectrometry. Particles entering central Alaska from the Pacific Marine environment had number concentrations ...

Glenn E. Shaw

1983-05-01T23:59:59.000Z

264

Orbits and reversals of a drop rolling inside a horizontal circular hydraulic jump  

E-Print Network (OSTI)

We explore the complex dynamics of a non-coalescing drop of moderate size inside a circular hydraulic jump of the same liquid formed on a horizontal disk. In this situation the drop is moving along the jump and one observes two different motions: a periodic one (it orbitates at constant speed) and an irregular one involving reversals of the orbital motion. Modeling the drop as a rigid sphere exchanging friction with liquid across a thin film of air, we recover the orbital motion and the internal rotation of the drop. This internal rotation is experimentally observed.

Alexis Duchesne; Clément Savaro; Luc Lebon; Christophe Pirat; Laurent Limat

2013-01-29T23:59:59.000Z

265

Investigation of the particle size distribution and particle density characteristics of Douglas fir hogged fuel fly ash collected under known combustion conditions. Technical Progress Report No. 2  

DOE Green Energy (OSTI)

The increased interest in wood as a fuel source, coupled with the increasing demand to control the emission generated by wood combustion, has created a need for information characterizing the emissions that occur for given combustion conditions. This investigation characterizes the carbon char and inorganic fly ash size and density distribution for each of thirty-eight Douglas fir bark samples collected under known conditions of combustion.

Lang, A.J.; Junge, D.C.

1978-12-01T23:59:59.000Z

266

A Bayesian Approach to Upscaling and Downscaling of Aircraft Measurements of Ice Particle Counts and Size Distributions  

Science Conference Proceedings (OSTI)

This study addresses the issue of how to upscale cloud-sized in situ measurements of ice to yield realistic simulations of ice clouds for a variety of modeling studies. Aircraft measurements of ice particle counts along a 79 km zigzag path were ...

A. R. Jameson; A. J. Heymsfield

267

A Bayesian Approach to Upscaling and Downscaling of Aircraft Measurements of Ice Particle Counts and Size Distributions  

Science Conference Proceedings (OSTI)

This study addresses the issue of how to upscale cloud-sized in situ measurements of ice to yield realistic simulations of ice clouds for a variety of modeling studies. Aircraft measurements of ice particle counts along a 79-km zigzag path were ...

A. R. Jameson; A. J. Heymsfield

2013-09-01T23:59:59.000Z

268

Drag and drop display & builder  

SciTech Connect

The Drag and Drop (DnD) Display & Builder is a component-oriented system that allows users to create visual representations of data received from data acquisition systems. It is an upgrade of a Synoptic Display mechanism used at Fermilab since 2002. Components can be graphically arranged and logically interconnected in the web-startable Project Builder. Projects can be either lightweight AJAX- and SVG-based web pages, or they can be started as Java applications. The new version was initiated as a response to discussions between the LHC Controls Group and Fermilab.

Bolshakov, Timofei B.; Petrov, Andrey D.; /Fermilab

2007-12-01T23:59:59.000Z

269

Very Early Formation of Big, Liquid Drops Revealed by ZDR in Continental Cumulus  

Science Conference Proceedings (OSTI)

Examination of the early radar echo histories of several vigorous, cumulus clouds in northeast Colorado and northwest Kansas, with sensitive, dual-polarization radar, reveals the formation of millimeter-sized water drops at about the same time ...

Charles A. Knight

2006-07-01T23:59:59.000Z

270

Jet Drops Produced by Bubbles Bursting at the Surface of Seawater  

Science Conference Proceedings (OSTI)

Several empirical formulas were reported to describe the production of jet drops by bubbles bursting at the surface of seawater; they were, however, based on scanty data. Recent observations of Spiel have provided new data for intermediate-size ...

Jin Wu

2002-11-01T23:59:59.000Z

271

System Size, Energy and Centrality Dependence of Pseudorapidity Distributions of Charged Particles in Relativistic Heavy Ion Collisions  

E-Print Network (OSTI)

We present the first measurements of the pseudorapidity distribution of primary charged particles in Cu+Cu collisions as a function of collision centrality and energy, \\sqrtsnn = 22.4, 62.4 and 200 GeV, over a wide range of pseudorapidity, using the PHOBOS detector. Making a global comparison of Cu+Cu and Au+Au results, we find that the total number of produced charged particles and the rough shape (height and width) of the pseudorapidity distributions are determined by the number of nucleon participants. More detailed studies reveal that a more precise matching of the shape of the Cu+Cu and Au+Au pseudorapidity distributions over the full range of pseudorapidity occurs for the same Npart/2A value rather than the same Npart value. In other words, it is the collision geometry rather than just the number of nucleon participants that drives the detailed shape of the pseudorapidity distribution and its centrality dependence at RHIC energies.

B. Alver; B. B. Back; M. D. Baker; M. Ballintijn; D. S. Barton; R. R. Betts; R. Bindel; W. Busza; Z. Chai; V. Chetluru; E. García; T. Gburek; K. Gulbrandsen; J. Hamblen; I. Harnarine; C. Henderson; D. J. Hofman; R. S. Hollis; R. Ho?y?ski; B. Holzman; A. Iordanova; J. L. Kane; P. Kulinich; C. M. Kuo; W. Li; W. T. Lin; C. Loizides; S. Manly; A. C. Mignerey; R. Nouicer; A. Olszewski; R. Pak; C. Reed; E. Richardson; C. Roland; G. Roland; J. Sagerer; I. Sedykh; C. E. Smith; M. A. Stankiewicz; P. Steinberg; G. S. F. Stephans; A. Sukhanov; A. Szostak; M. B. Tonjes; A. Trzupek; G. J. van Nieuwenhuizen; S. S. Vaurynovich; R. Verdier; G. I. Veres; P. Walters; E. Wenger; D. Willhelm; F. L. H. Wolfs; B. Wosiek; K. Wo?niak; S. Wyngaardt; B. Wys?ouch

2007-09-25T23:59:59.000Z

272

The spatial distribution of mineral dust and its shortwave radiative forcing over North Africa: Modeling sensitivities to dust emissions and aerosol size treatments  

Science Conference Proceedings (OSTI)

A fully coupled meteorology-chemistry-aerosol model (WRF-Chem) with the implementation of two dust emission schemes (GOCART and DUSTRAN) into two aerosol models (MADE/SORGAM and MOSAIC) is applied over North Africa to investigate the modeling sensitivities to dust emissions and aerosol size treatments in simulating mineral dust and its shortwave (SW) radiative forcing. Model results of the spatial distribution of mineral dust and its radiative forcing are evaluated using measurements from the AMMA SOP0 campaign in January and February of 2006 over North Africa. Our study suggests that the size distribution of emitted dust can result in significant differences (up to 100%) in simulating mineral dust and its SW radiative forcing. With the same dust emission and dry deposition processes, two aerosol models, MADE/SORGAM and MOSAIC, can yield large difference in size distributions of dust particles due to their different aerosol size treatments using modal and sectional approaches respectively. However, the difference between the two aerosol models in simulating the mass concentrations and the SW radiative forcing of mineral dust is small (< 10%). The model simulations show that mineral dust increases AOD by a factor of 2, heats the lower atmosphere (1-3 km) with a maximum rate of 0.7?0.5 K day-1 below 1 km, and reduces the downwelling SW radiation by up to 25 W m-2 on 24-hour average at surface, highlighting the importance of including dust radiative impact in understanding the regional climate of North Africa. When compared to the available measurements, WRF-Chem simulations can generally capture the measured features of mineral dust and its radiative properties over North Africa, suggesting that the model can be used to perform more extensive simulations of regional climate over North Africa.

Zhao, Chun; Liu, Xiaohong; Leung, Lai-Yung R.; Johnson, Ben; McFarlane, Sally A.; Gustafson, William I.; Fast, Jerome D.; Easter, Richard C.

2010-09-20T23:59:59.000Z

273

Evidence for departure from a power-law flare size distribution for a small solar active region  

E-Print Network (OSTI)

Active region 11029 was a small, highly flare-productive solar active region observed at a time of extremely low solar activity. The region produced only small flares: the largest of the $>70$ Geostationary Observational Environmental Satellite (GOES) events for the region has a peak 1--$8{\\AA}$ flux of $2.2\\times 10^{-6} {\\rm W} {\\rm m}^{-2}$ (GOES C2.2). The background-subtracted GOES peak-flux distribution suggests departure from power-law behavior above $10^{-6} {\\rm W} {\\rm m}^{-2}$, and a Bayesian model comparison strongly favors a power-law plus rollover model for the distribution over a simple power-law model. The departure from the power law is attributed to this small active region having a finite amount of energy. The rate of flaring in the region varies with time, becoming very high for two days coinciding with the onset of an increase in complexity of the photospheric magnetic field. The observed waiting-time distribution for events is consistent with a piecewise-constant Poisson model. These res...

Wheatland, M S

2010-01-01T23:59:59.000Z

274

Magnetically focused liquid drop radiator  

DOE Patents (OSTI)

A magnetically focused liquid drop radiator for application in rejecting energy from a spacecraft, characterized by a magnetizable liquid or slurry disposed in operative relationship within the liquid droplet generator and its fluid delivery system, in combination with magnetic means disposed in operative relationship around a liquid droplet collector of the LDR. The magnetic means are effective to focus streams of droplets directed from the generator toward the collector, thereby to assure that essentially all of the droplets are directed into the collector, even though some of the streams may be misdirected as they leave the generator. The magnetic focusing means is also effective to suppress splashing of liquid when the droplets impinge on the collector.

Botts, T.E.; Powell, J.R.; Lenard, R.

1984-12-10T23:59:59.000Z

275

Irreversible volume growth in polymer-bonded powder systems: effects of crystalline anisotropy, particle size distribution, and binder strength  

Science Conference Proceedings (OSTI)

Pressed-powdered crystallites of intrinsically anisotropic materials have been shown to undergo irreversible volume expansion when subjected to repeated cycles of heating and cooling. We develop a coarse-grained (micron-scale) interaction Hamiltonian for this system and perform molecular dynamics simulations, which quantitatively reproduce the experimentally observed irreversible growth. The functional form and values of the interaction parameters at the coarse-grained level are motivated by our knowledge at the atomic/molecular scale, and allows a simple way to incorporate the effect of polymeric binder. We demonstrate that irreversible growth happens only in the presence of intrinsic crystalline anisotropy of the powder material, is mediated by particles much smaller than the average crystallite size, and can be significantly reduced in the presence of high-strength polymeric binder with elevated glass transition temperatures.

Maiti, A; Gee, R H; Hoffman, D; Fried, L E

2007-08-22T23:59:59.000Z

276

Analytical Solutions to the Stochastic Kinetic Equation for Liquid and Ice Particle Size Spectra. Part I: Small-Size Fraction  

Science Conference Proceedings (OSTI)

The kinetic equation of stochastic condensation for cloud drop size spectra is extended to account for crystalline clouds and also to include the accretion–aggregation process. The size spectra are separated into small and large size fractions ...

Vitaly I. Khvorostyanov; Judith A. Curry

2008-07-01T23:59:59.000Z

277

Colloidal Shape Effects in Evaporating Drops  

E-Print Network (OSTI)

We explore the influence of particle shape on the behavior of evaporating drops. A first set of experiments discovered that particle shape modifies particle deposition after drying. For sessile drops, spheres are deposited in a ring-like stain, while ellipsoids are deposited uniformly. Experiments elucidate the kinetics of ellipsoids and spheres at the drop's edge. A second set of experiments examined evaporating drops confined between glass plates. In this case, colloidal particles coat the ribbon-like air-water interface, forming colloidal monolayer membranes (CMMs). As particle anisotropy increases, CMM bending rigidity was found to increase, which in turn introduces a new mechanism that produces a uniform deposition of ellipsoids and a heterogeneous deposition of spheres after drying. A final set of experiments investigates the effect of surfactants in evaporating drops. The radially outward flow that pushes particles to the drop's edge also pushes surfactants to the drop's edge, which leads to a radially inward flow on the drop surface. The presence of radially outward flows in the bulk fluid and radially inward flows at the drop surface creates a Marangoni eddy, among other effects, which also modifies deposition after drying.

Peter J. Yunker; Tim Still; A. G. Yodh

2013-08-08T23:59:59.000Z

278

Net Metering Policy Development and Distributed Solar Generation in Minnesota: Overview of Trends in Nationwide Policy Development and Implications of Increasing the Eligible System Size Cap  

DOE Green Energy (OSTI)

The goal of the Minnesota net metering policy is to give the maximum possible encouragement to distributed generation assets, especially solar electric systems (MN 2008). However, according to a published set of best practices (NNEC 2008) that prioritize the maximum development of solar markets within states, the Minnesota policy does not incorporate many of the important best practices that may help other states transform their solar energy markets and increase the amount of grid-connected distributed solar generation assets. Reasons cited include the low system size limit of 40kW (the best practices document recommends a 2 MW limit) and a lack of language protecting generators from additional utility fees. This study was conducted to compare Minnesota's policies to national best practices. It provides an overview of the current Minnesota policy in the context of these best practices and other jurisdictions' net metering policies, as well as a qualitative assessment of the impacts of raising the system size cap within the policy based on the experiences of other states.

Doris, E.; Busche, S.; Hockett, S.

2009-12-01T23:59:59.000Z

279

Improved Drop Generators for Calibration of Drop Spectrometers and Use in Laboratory Cloud Physics Experiments  

Science Conference Proceedings (OSTI)

Drop generators have been developed at NCAR based on the “wire egression” principle. They are outstanding in their flexibility and simplicity. Drops ranging in diameter from 6 ?m to 1 mm have been generated with one model. Application of the ...

Theodore W. Cannon; Walter W. Grotewold

1980-07-01T23:59:59.000Z

280

Distribution:  

Office of Legacy Management (LM)

JAN26 19% JAN26 19% Distribution: OR00 Attn: h.H.M.Roth DFMusser ITMM MMMann INS JCRyan FIw(2) Hsixele SRGustavson, Document rocm Formal file i+a@mmm bav@ ~@esiaw*cp Suppl. file 'Br & Div rf's s/health (lic.only) UNITED STATES ATOMIC ENERGY COMMISSION SPECIAL NUCLEAB MATERIAL LICENSE pursuant to the Atomic Energy Act of 1954 and Title 10, Code of Federal Regulations, Chapter 1, P&t 70, "Special Nuclear Material Reg)llatiqm," a license is hereby issued a$hortztng the licensee to rekeive and possess the special nuclear material designated below; to use such special nuclear mat&ial for the purpose(s) and at the place(s) designated below; and to transfer such material to per&s authorized to receive it in accordance with the regula,tions in said Part.

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

The Impact of Size Distribution Assumptions in a Bulk One-Moment Microphysics Scheme on Simulated Surface Precipitation and Storm Dynamics during a Low-Topped Supercell Case in Belgium  

Science Conference Proceedings (OSTI)

In this research the impact of modifying the size distribution assumptions of the precipitating hydrometeors in a bulk one-moment microphysics scheme on simulated surface precipitation and storm dynamics has been explored for long-lived low-topped ...

Kwinten Van Weverberg; Nicole P. M. van Lipzig; Laurent Delobbe

2011-04-01T23:59:59.000Z

282

Development of an Inexpensive Raindrop Size Spectrometer  

Science Conference Proceedings (OSTI)

The deployment of weather radar, notably in mountainous terrain with many microclimates, requires the use of several or even many drop size spectrometers to provide confidence in the quantitative relation between radar reflectivity and rainfall. ...

William Henson; Geoff Austin; Harry Oudenhoven

2004-11-01T23:59:59.000Z

283

The Concept of “Normalized” Distribution to Describe Raindrop Spectra: A Tool for Cloud Physics and Cloud Remote Sensing  

Science Conference Proceedings (OSTI)

The shape of the drop size distribution (DSD) reflects the physics of rain. The DSD is the result of the microphysical processes that transform the condensed water into rain. The question of the DSD is also central in radar meteorology, because ...

Jacques Testud; Stéphane Oury; Robert A. Black; Paul Amayenc; Xiankang Dou

2001-06-01T23:59:59.000Z

284

Adiabatic two-phase frictional pressure drops in microchannels  

SciTech Connect

Two-phase pressure drops were measured over a wide range of experimental test conditions in two sizes of microchannels (sight glass tubes 0.509 and 0.790 mm) for two refrigerants (R-134a and R-245fa). Similar to the classic Moody diagram in single-phase flow, three zones were distinguishable when plotting the variation of the two-phase friction factor versus the two-phase Reynolds number: a laminar regime for Re{sub TP} < 2000, a transition regime for 2000 {<=} Re{sub TP} < 8000 and a turbulent regime for Re{sub TP} {>=} 8000. The laminar zone yields a much sharper gradient than in single-phase flow. The transition regime is not predicted well by any of the prediction methods for two-phase frictional pressure drops available in the literature. This is not unexpected since only a few data are available for this region in the literature and most methods ignore this regime, jumping directly from laminar to turbulent flow at Re{sub TP} = 2000. The turbulent zone is best predicted by the Mueller-Steinhagen and Heck correlation. Also, a new homogeneous two-phase frictional pressure drop has been proposed here with a limited range of application. (author)

Revellin, Remi; Thome, John R. [EPFL, STI ISE LTCM, ME Gl 464, Station 9, CH-1015 Lausanne (Switzerland)

2007-07-15T23:59:59.000Z

285

The Effect of Vertical Turbulent Fluctuations in the Atmosphere on the Collection of Aerosol Particles by Cloud Drops  

Science Conference Proceedings (OSTI)

A one-dimensional model of the effect of the vertical component of atmospheric turbulent fluctuations on the collection of micron-size aerosol particles by cloud drops is presented. The model includes simultaneous effects of the differential ...

S. N. Grover; H. R. Pruppacher

1985-11-01T23:59:59.000Z

286

COAGULATION CALCULATIONS OF ICY PLANET FORMATION AT 15-150 AU: A CORRELATION BETWEEN THE MAXIMUM RADIUS AND THE SLOPE OF THE SIZE DISTRIBUTION FOR TRANS-NEPTUNIAN OBJECTS  

Science Conference Proceedings (OSTI)

We investigate whether coagulation models of planet formation can explain the observed size distributions of trans-Neptunian objects (TNOs). Analyzing published and new calculations, we demonstrate robust relations between the size of the largest object and the slope of the size distribution for sizes 0.1 km and larger. These relations yield clear, testable predictions for TNOs and other icy objects throughout the solar system. Applying our results to existing observations, we show that a broad range of initial disk masses, planetesimal sizes, and fragmentation parameters can explain the data. Adding dynamical constraints on the initial semimajor axis of 'hot' Kuiper Belt objects along with probable TNO formation times of 10-700 Myr restricts the viable models to those with a massive disk composed of relatively small (1-10 km) planetesimals.

Kenyon, Scott J. [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Bromley, Benjamin C., E-mail: skenyon@cfa.harvard.edu, E-mail: bromley@physics.utah.edu [Department of Physics, University of Utah, 201 JFB, Salt Lake City, UT 84112 (United States)

2012-03-15T23:59:59.000Z

287

Alternative Fuels Data Center: Drop-In Biofuels  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Drop-In Biofuels to Drop-In Biofuels to someone by E-mail Share Alternative Fuels Data Center: Drop-In Biofuels on Facebook Tweet about Alternative Fuels Data Center: Drop-In Biofuels on Twitter Bookmark Alternative Fuels Data Center: Drop-In Biofuels on Google Bookmark Alternative Fuels Data Center: Drop-In Biofuels on Delicious Rank Alternative Fuels Data Center: Drop-In Biofuels on Digg Find More places to share Alternative Fuels Data Center: Drop-In Biofuels on AddThis.com... More in this section... Biobutanol Drop-In Biofuels Methanol P-Series Renewable Natural Gas xTL Fuels Drop-In Biofuels Drop-in biofuels are hydrocarbon fuels substantially similar to gasoline, diesel, or jet fuels. These fuels can be made from a variety of biomass feedstocks including crop residues, woody biomass, dedicated energy crops,

288

An Inferred Climatology of Icing Conditions Aloft, Including Supercooled Large Drops. Part II: Europe, Asia, and the Globe  

Science Conference Proceedings (OSTI)

Because of a lack of regular, direct measurements, limited information is available about the frequency and the spatial and temporal distribution of icing conditions aloft, including supercooled large drops (SLD). Research aircraft provide in ...

Ben C. Bernstein; Christine Le Bot

2009-08-01T23:59:59.000Z

289

An Inferred Climatology of Icing Conditions Aloft, Including Supercooled Large Drops. Part I: Canada and the Continental United States  

Science Conference Proceedings (OSTI)

Because of a lack of regular, direct measurements, little information is available about the frequency and spatial and temporal distribution of icing conditions aloft, including supercooled large drops (SLD). Research aircraft provide in situ ...

Ben C. Bernstein; Cory A. Wolff; Frank McDonough

2007-11-01T23:59:59.000Z

290

Microphysical Interpretation of Multi-Parameter Radar Measurements in Rain. Part II: Estimation of Raindrop Distribution Parameters by Combined Dual-Wavelength and Polarization Measurements  

Science Conference Proceedings (OSTI)

The radar reflectivity weighted mean axis ratio R¯ and the variance of the axis ratio distribution ?R2 of an ensemble of raindrops can be estimated from polarization radar measurements. If the shape function relating axis ratio to drop size is ...

A. R. Jameson

1983-07-01T23:59:59.000Z

291

A kinematic wave theory of capacity drop  

E-Print Network (OSTI)

Capacity drop at active bottlenecks is one of the most puzzling traffic phenomena, but a thorough understanding is practically important for designing variable speed limit and ramp metering strategies. In this study, we attempt to develop a simple model of capacity drop within the framework of kinematic wave theory based on the observation that capacity drop occurs when an upstream queue forms at an active bottleneck. In addition, we assume that the fundamental diagrams are continuous in steady states. This assumption is consistent with observations and can avoid unrealistic infinite characteristic wave speeds in discontinuous fundamental diagrams. A core component of the new model is an entropy condition defined by a discontinuous boundary flux function. For a lane-drop area, we demonstrate that the model is well-defined, and its Riemann problem can be uniquely solved. We theoretically discuss traffic stability with this model subject to perturbations in density, upstream demand, and downstream supply. We clarify that discontinuous flow-density relations, or so-called "discontinuous" fundamental diagrams, are caused by incomplete observations of traffic states. Theoretical results are consistent with observations in the literature and are verified by numerical simulations and empirical observations. We finally discuss potential applications and future studies.

Wen-Long Jin; Qi-Jian Gan; Jean-Patrick Lebacque

2013-10-09T23:59:59.000Z

292

Raindrop Velocity Spectrometer for Drop Chemistry Investigations  

Science Conference Proceedings (OSTI)

The design of an instrument that sorts raindrops according to fall speed is described. The apparatus consists of two rotating disks, the upper one allowing rain to fall through a slit into collectors on the lower disk. Drops are collected in a ...

S. G. Bradley

1985-06-01T23:59:59.000Z

293

A Simple Technique for Simultaneous Suspension of Multiple Drops in a Small Vertical Wind Tunnel  

Science Conference Proceedings (OSTI)

A simple technique is described by which multiple millimeter-size water drops can be simultaneously suspended in an air stream above the test section of a 12 × 12 cm cross section of a vertical wind tunnel. Horizontal profiles of the vertical air ...

A. K. Kamra; D. V. Ahire

1985-09-01T23:59:59.000Z

294

Vaporization modeling of petroleum-biofuel drops using a hybrid multi-component approach  

Science Conference Proceedings (OSTI)

Numerical modeling of the vaporization characteristics of multi-component fuel mixtures is performed in this study. The fuel mixtures studied include those of binary components, biodiesel, diesel-biodiesel, and gasoline-ethanol. The use of biofuels has become increasingly important for reasons of environmental sustainability. Biofuels are often blended with petroleum fuels, and the detailed understanding of the vaporization process is essential to designing a clean and efficient combustion system. In this study, a hybrid vaporization model is developed that uses continuous thermodynamics to describe petroleum fuels and discrete components to represent biofuels. The model is validated using the experimental data of n-heptane, n-heptane-n-decane mixture, and biodiesel. Since biodiesel properties are not universal due to the variation in feedstock, methods for predicting biodiesel properties based on the five dominant fatty acid components are introduced. Good levels of agreement in the predicted and measured drop size histories are obtained. Furthermore, in modeling the diesel-biodiesel drop, results show that the drop lifetime increases with the biodiesel concentration in the blend. During vaporization, only the lighter components of diesel fuel vaporize at the beginning. Biodiesel components do not vaporize until some time during the vaporization process. On the other hand, results of gasoline-ethanol drops indicate that both fuels start to vaporize once the process begins. At the beginning, the lighter components of gasoline have a slightly higher vaporization rate than ethanol. After a certain time, ethanol vaporizes faster than the remaining gasoline components. At the end, the drop reduces to a regular gasoline drop with heavier components. Overall, the drop lifetime increases as the concentration of ethanol increases in the drop due to the higher latent heat. (author)

Zhang, Lei; Kong, Song-Charng [Department of Mechanical Engineering, Iowa State University, 2025 Black Engineering Building, Ames, IA 50011 (United States)

2010-11-15T23:59:59.000Z

295

A Methodology for Estimating the Parameters of a Gamma Raindrop Size Distribution Model from Polarimetric Radar Data: Application to a Squall-Line Event from the TRMM/Brazil Campaign  

Science Conference Proceedings (OSTI)

A methodology is proposed for estimating the parameters of a gamma raindrop size distribution model from radar measurements of Zh, Zdr, and Kdp at S band. Previously developed algorithms by Gorgucci et al. are extended to cover low rain-rate ...

V. N. Bringi; Gwo-Jong Huang; V. Chandrasekar; E. Gorgucci

2002-05-01T23:59:59.000Z

296

Observations of the Distribution of Ice in Hurricanes  

Science Conference Proceedings (OSTI)

Observations of the type and distribution 0°C isotherm in three Atlantic hurricanes are presented. Supercooled drops, graupel, columns and aggregated snowflakes were observed. The supercooled drops were found only in convective updrafts stronger ...

R. A. Black; J. Hallett

1986-04-01T23:59:59.000Z

297

Packet Drop Avoidance for High-speed network transmission protocol  

SciTech Connect

As network bandwidth continues to grow and longer paths are used to exchange large scientific data between storage systems and GRID computation, it has become increasingly obvious that there is a need to deploy a packet drop avoidance mechanism into network transmission protocols. Current end-to-end congestion avoidance mechanisms used in Transmission Control Protocol (TCP) have worked well on low bandwidth delay product networks, but with newer high-bandwidth delay networks they have shown to be inefficient and prone to unstable. This is largely due to increased network bandwidth coupled with changes in internet traffic patterns. These changes come from a variety of new network applications that are being developed to take advantage of the increased network bandwidth. This paper will examine the end-to-end congestion avoidance mechanism and perform a step-by-step analysis of its theory. In addition we will propose an alternative approach developed as part of a new network transmission protocol. Our alternative protocol uses a packet drop avoidance (PDA) mechanism built on top of the maximum burst size (MBS) theory combined with a real-time available bandwidth algorithm.

Jin, Guojun

2004-05-01T23:59:59.000Z

298

Temperature Fitting Method Predicting Equidistant Voltage Drop of ...  

Science Conference Proceedings (OSTI)

High Temperature Compression Test to Determine the Anode Paste ... Temperature Fitting Method Predicting Equidistant Voltage Drop of Anode Nod in  ...

299

Drop Axis Ratios from a 2D Video Disdrometer  

Science Conference Proceedings (OSTI)

Results from an experiment to measure the drop shapes using a 2D video disdrometer (2DVD) are reported. Under calm conditions, drops were generated from a hose located on a bridge 80 m above ground, this height being sufficient to allow drop ...

Merhala Thurai; V. N. Bringi

2005-07-01T23:59:59.000Z

300

NCNR Magnetic Cluster Sizes in Recording Disks  

Science Conference Proceedings (OSTI)

... Presently, cluster sizes are believed to be about 10 nano meters to 15 nano meters, but accurate knowledge of the size distribution and even the ...

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Laboratory Measurements of Spontaneous Oscillations for Moderate-Size Raindrops  

Science Conference Proceedings (OSTI)

The natural oscillations of moderate-size raindrops were studied in a seven-story fall column using a computer-controlled generator to produce isolated water drops at terminal speed. Instantaneous shapes were photographed to obtain oscillation ...

Rodney J. Kubesh; Kenneth V. Beard

1993-04-01T23:59:59.000Z

302

Ice Cloud Particle Size Distributions and Pressure-Dependent Terminal Velocities from In Situ Observations at Temperatures from 0 to ?86 C  

Science Conference Proceedings (OSTI)

The primary goal of this study is to derive ice particle terminal velocities from micron to cm sizes and for atmospheric pressures covering the range 200–1000 hPa from data spanning a wide range of locations, temperatures, and altitudes and to ...

Andrew J. Heymsfield; Carl Schmitt; Aaron Bansemer

303

Impact Dynamics of Oxidized Liquid Metal Drops  

E-Print Network (OSTI)

With exposure to air, many liquid metals spontaneously generate an oxide layer on their surface. In oscillatory rheological tests, this skin is found to introduce a yield stress that typically dominates the elastic response but can be tuned by exposing the metal to hydrochloric acid solutions of different concentration. We systematically studied the normal impact of eutectic gallium-indium (eGaIn) drops under different oxidation conditions and show how this leads to two different dynamical regimes. At low impact velocity (or low Weber number), eGaIn droplets display strong recoil and rebound from the impacted surface when the oxide layer is removed. In addition, the degree of drop deformation or spreading during the impact is controlled by the oxide skin. We show that the scaling law known from ordinary liquids for the maximum spreading radius as a function of impact velocity can still be applied to the case of oxidized eGaIn if an effective Weber number $We^{\\star}$ is employed that uses an effective surface...

Xu, Qin; Jaeger, Heinrich M

2013-01-01T23:59:59.000Z

304

Drilling costs drop 7% in 1985  

SciTech Connect

Drilling costs dropped about 7% last year. This decline cancels a slight increase in 1984. Total costs to drill now run about 59% of the 1981 highs. Comparable figures for the previous 2 years are 63 and 61%. Deeper wells showed the biggest drops. Shallow well costs fell about 6%. Energy Information Administration (EIA) indexes drilling costs on a 1976 base year. Costs for shallow wells (5,000 ft or less) show an index about 138. Deeper wells have an index around 149. Cost declines were the greatest in West and North Texas and the Rockies, of 11%. The Northeast and Western areas showed greater than average declines, 9% or so. The High Plains, New Mexico, and Midcontinent areas recorded near the average 7% decline. Costs in South Louisiana, the Southeast, and Ark-La-Tex 2%. West Central Texas costs were off only 1%. The Southeast was essentially unchanged. Indexes by area show generally that drilling costs have declined since 1983. The summary here comes from EIA's ''Indexes and Estimates of Domestic Well Drilling Costs 1984 and 1985''. That report covers oil, gas, and dry hole costs, cost components, and overall costs.

Anderson, T.; Funk, V.

1986-03-24T23:59:59.000Z

305

Net Metering Policy Development and Distributed Solar Generation in Minnesota: Overview of Trends in Nationwide Policy Development and Implications of Increasing the Eligible System Size Cap  

NLE Websites -- All DOE Office Websites (Extended Search)

0 0 December 2009 Net Metering Policy Development in Minnesota: Overview of Trends in Nationwide Policy Development and Implications of Increasing the Eligible System Size Cap Elizabeth Doris, Sarah Busche, and Stephen Hockett National Renewable Energy Laboratory 1617 Cole Boulevard, Golden, Colorado 80401-3393 303-275-3000 * www.nrel.gov NREL is a national laboratory of the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Operated by the Alliance for Sustainable Energy, LLC Contract No. DE-AC36-08-GO28308 Technical Report NREL/TP-6A2-46670 December 2009 Net Metering Policy Development in Minnesota: Overview of Trends in Nationwide Policy Development and Implications of Increasing the Eligible System Size Cap

306

Shape oscillations of a viscoelastic drop  

SciTech Connect

Small-amplitude axisymmetric shape deformations of a viscoelastic liquid drop in microgravity are theoretically analyzed. Using the Jeffreys constitutive equation for linear viscoelasticity, the characteristic equation for the frequency and decay factor of the shape oscillations is derived. Asymptotic analysis of this equation is performed in the low- and high-viscosity limits and for the cases of small, moderate, and large elasticities. Elastic effects are shown to give rise to a type of shape oscillation that does not depend on the surface tension. The existence of such oscillations is confirmed by numerical solution of the characteristic equation in various regimes. A method for determining the viscoelastic properties of highly viscous liquids based upon experimental measurements of the frequency and damping rate of such shape oscillations is suggested.

Khismatullin, Damir B.; Nadim, Ali

2001-06-01T23:59:59.000Z

307

Horizontal Drop of 21- PWR Waste Package  

SciTech Connect

The objective of this calculation is to determine the structural response of the waste package (WP) dropped horizontally from a specified height. The WP used for that purpose is the 21-Pressurized Water Reactor (PWR) WP. The scope of this document is limited to reporting the calculation results in-terms of stress intensities. This calculation is associated with the WP design and was performed by the Waste Package Design group in accordance with the ''Technical Work Plan for: Waste Package Design Description for LA'' (Ref. 16). AP-3.12Q, ''Calculations'' (Ref. 1 1) is used to perform the calculation and develop the document. The sketches attached to this calculation provide the potential dimensions and materials for the 21-PWR WP design.

A.K. Scheider

2007-01-31T23:59:59.000Z

308

Load drop evaluation for TWRS FSAR  

Science Conference Proceedings (OSTI)

Operational or remediation activities associated with existing underground high-level waste storage tank structures at the Hanford Site often require the installation/removal of various equipment items. To gain tank access for installation or removal of this equipment, large concrete cover blocks must be removed and reinstalled in existing concrete pits above the tanks. An accidental drop of the equipment or cover blocks while being moved over the tanks that results in the release of contaminants to the air poses a potential risk to onsite workers or to the offsite public. To minimize this potential risk, the use of critical lift hoisting and rigging procedures and restrictions on lift height are being considered during development of the new tank farm Basis for Interim Operation and Final Safety Analysis Report. The analysis contained herein provides information for selecting the appropriate lift height restrictions for these activities.

Julyk, L.J.; Ralston, G.L.

1996-09-30T23:59:59.000Z

309

A Self-Evaluating Disdrometer for the Measurement of Raindrop Size and Charge at the Ground  

Science Conference Proceedings (OSTI)

A disdrometer for the measurement of the co-spectra of raindrop size and charge is described which can evaluate to a significant extent spurious data caused by unavoidable drop overlap within the charge detector volume. The sizes of individual ...

C. D. Stow; K. Jones

1981-10-01T23:59:59.000Z

310

Size Effects  

Science Conference Proceedings (OSTI)

Mar 5, 2013 ... An Explanation of the Power-Exponent in the Size Effect on Strength in ... in terms of the Taylor-type resistance in the dislocation network in the specimen. ... hysteresis and loss in pseudoelasticity with decrease in sample size.

311

Microwave Dielectric Heating of Drops in Microfluidic Devices  

E-Print Network (OSTI)

We present a technique to locally and rapidly heat water drops in microfluidic devices with microwave dielectric heating. Water absorbs microwave power more efficiently than polymers, glass, and oils due to its permanent molecular dipole moment that has a large dielectric loss at GHz frequencies. The relevant heat capacity of the system is a single thermally isolated picoliter drop of water and this enables very fast thermal cycling. We demonstrate microwave dielectric heating in a microfluidic device that integrates a flow-focusing drop maker, drop splitters, and metal electrodes to locally deliver microwave power from an inexpensive, commercially available 3.0 GHz source and amplifier. The temperature of the drops is measured by observing the temperature dependent fluorescence intensity of cadmium selenide nanocrystals suspended in the water drops. We demonstrate characteristic heating times as short as 15 ms to steady-state temperatures as large as 30 degrees C above the base temperature of the microfluidi...

Issadore, David; Brown, Keith A; Sandberg, Lori; Weitz, David; Westervelt, Robert M

2009-01-01T23:59:59.000Z

312

Fat Man Dropped on Nagasaki | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

Fat Man Dropped on Nagasaki | National Nuclear Security Administration Fat Man Dropped on Nagasaki | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog Home > About Us > Our History > NNSA Timeline > Fat Man Dropped on Nagasaki Fat Man Dropped on Nagasaki August 09, 1945 Nagasaki, Japan Fat Man Dropped on Nagasaki The implosion model plutonium bomb, called Fat Man, is dropped on Nagasaki,

313

government share of university r&d drops - TMS  

Science Conference Proceedings (OSTI)

11/3 - GOVERNMENT SHARE OF UNIVERSITY R&D DROPS. In FY2008, universities reported science and engineering research and development ...

314

Little Boy Dropped on Hiroshima | National Nuclear Security Administra...  

NLE Websites -- All DOE Office Websites (Extended Search)

Little Boy Dropped on Hiroshima | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response...

315

Little Boy Dropped on Hiroshima | National Nuclear Security Administra...  

National Nuclear Security Administration (NNSA)

NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog Home > About Us > Our History > NNSA Timeline > Little Boy Dropped on Hiroshima Little Boy...

316

Pore size estimation  

Science Conference Proceedings (OSTI)

A novel method for characterization of any porous structure is presented. The principle of the method is simple scanning a plane surface of a cellular material and consequent digital image analysis of the scan. Eleven samples of bread baked from dough ... Keywords: foams, image analysis, modelling the structure, plane cut visualization, pore size distribution, voronoi tessellation

Tomas Matousek; Petr Ponizil; Filip Kremen; Iva Buresova; Petra Dvorakova

2011-07-01T23:59:59.000Z

317

STRESS CORROSION CRACKING IN TEAR DROP SPECIMENS  

SciTech Connect

Laboratory tests were conducted to investigate the stress corrosion cracking (SCC) of 304L stainless steel used to construct the containment vessels for the storage of plutonium-bearing materials. The tear drop corrosion specimens each with an autogenous weld in the center were placed in contact with moist plutonium oxide and chloride salt mixtures. Cracking was found in two of the specimens in the heat affected zone (HAZ) at the apex area. Finite element analysis was performed to simulate the specimen fabrication for determining the internal stress which caused SCC to occur. It was found that the tensile stress at the crack initiation site was about 30% lower than the highest stress which had been shifted to the shoulders of the specimen due to the specimen fabrication process. This finding appears to indicate that the SCC initiation took place in favor of the possibly weaker weld/base metal interface at a sufficiently high level of background stress. The base material, even subject to a higher tensile stress, was not cracked. The relieving of tensile stress due to SCC initiation and growth in the HAZ and the weld might have foreclosed the potential for cracking at the specimen shoulders where higher stress was found.

Lam, P; Philip Zapp, P; Jonathan Duffey, J; Kerry Dunn, K

2009-05-01T23:59:59.000Z

318

Dependence of drop speed on nozzle diameter, viscosity and drive amplitude in drop-on-demand ink-jet printing  

E-Print Network (OSTI)

recent numerical codes developed by collaborators in the University of Leeds, and from simple models for drop-on-demand fluid jetting resulting from physical laws...

Hoath, S.D.; Hsiao, W.-K.; Jung, S.; Martin, G.D.; Hutchings, I.M.

2011-01-01T23:59:59.000Z

319

Analytical Solutions for Cloud-Drop Concentration  

Science Conference Proceedings (OSTI)

This note compares and evaluates the analytical solutions of Squires and Twomey for cloud droplet concentration. Either solution is likely to be fairly accurate (±30%) when the slope parameter (?) of the cloud condensation nuclei distribution is ...

David B. Johnson

1981-01-01T23:59:59.000Z

320

Japan Denies Report It Dropped Proposal to Host Fusion Reactor  

E-Print Network (OSTI)

Print Japan Denies Report It Dropped Proposal to Host Fusion Reactor June 22 (Bloomberg) -- Japan's science ministry denied a media report the country dropped its bid to host the world's first nuclear fusion reactor, a decision that would end a standoff with France to site the 4.6 billion-euro ($5

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Strategic planning of recycling drop-off stations and collection network by multiobjective programming  

SciTech Connect

Effective planning of solid-waste recycling programs is a substantial challenge to the current solid-waste management systems in Taiwan. Due to the rapid depletion of landfill space and the continuing delay in construction programs of municipal incinerators, solid-waste management strategies have to be reorganized in light of the success of recycling, recovery, and reuse of secondary materials. One of these efforts is how to effectively allocate recycling drop-off stations of appropriate size and how to design efficient collection-vehicle routing and scheduling programs in the solid waste collection network. This management strategy is particularly important in the privatized system with recycling containers and material recovery facilities (MRFs) owned by one agency. This research seeks multiobjective evaluation of the trade-off between the number and size of drop-off stations, the population covered in the service network, the average walking distance to drop-off stations by the population, and the distance traveled by collection vehicles. It also illustrates the use of the multiobjective nonlinear mixed integer programming model to achieve such goals that are solved by the genetic algorithms (GA) in a geographical information system (GIS) platform. The case study shows the application potential of such a methodology in the city of Kaohsiung in Taiwan.

Chang, N.; Wei, Y.L. (National Cheng-Kung Univ., Tainan (Taiwan, Province of China). Dept. of Environmental Engineering)

1999-08-01T23:59:59.000Z

322

A Laboratory Study of Pressure Losses in Residential Air Distribution  

NLE Websites -- All DOE Office Websites (Extended Search)

A Laboratory Study of Pressure Losses in Residential Air Distribution A Laboratory Study of Pressure Losses in Residential Air Distribution Systems Speaker(s): Bass Abushakra Date: March 7, 2002 - 12:00pm Location: Bldg. 90 Seminar Host/Point of Contact: Duo Wang An experimental study was conducted to evaluate the pressure drop of residential air distribution system components that are either not available or poorly described in existing duct design literature. The tests were designed to imitate cases normally found in typical residential and light commercial installations. The study included three different sizes of flexible ducts, under different compression configurations, splitter boxes, supply boots, and a fresh air intake hood. The experimental tests apparatus followed ASHRAE Standard 120P - Methods of Testing to Determine Flow

323

Drop Size Ambiguities in the Retrieval of Precipitation Profiles from Dual-Frequency Radar Measurements  

Science Conference Proceedings (OSTI)

The threat of flooding from landfalling tropical cyclones is a function of the local variation in rain rate and rain accumulation. To date, these have been inferred from single-frequency radar reflectivity measurements. However, the Tropical ...

Ziad S. Haddad; Jonathan P. Meagher; Stephen L. Durden; Eric A. Smith; Eastwood Im

2006-01-01T23:59:59.000Z

324

Influence of the time-dependent surfactant adsorption on the lifetime of a drop pressed by buoyancy against a planar interface  

E-Print Network (OSTI)

Emulsion Stability Simulations (ESS) of deformable droplets are used to study the influence of the time-dependent adsorption on the coalescence time of a 200-$\\mu$m drop of soybean oil pressed by buoyancy against a planar water/oil interface. The interface is represented by a 5000-$\\mu$m drop of oil fixed in the space. The movement of the small drop is determined by the interaction forces between the drops, the buoyancy force, and its thermal interaction with the solvent. The interaction forces depend on the surface concentration of surfactant molecules at the oil/water interfaces. Assuming diffusion limited adsorption, the surface excess of the surfactant becomes a function of its apparent diffusion constant, $D_{app}$. Distinct probability distributions of the coalescence time are obtained depending on the magnitude of $D_{app}$. The origin and the significance of these distributions are discussed.

Clara Rojas; Maximo Garcia-Sucre; German Urbina-Villalba

2013-05-23T23:59:59.000Z

325

Production Functions of Film Drops by Bursting Bubbles  

Science Conference Proceedings (OSTI)

Experimental results of Blanchard and Syzdek and of Resch and Afeti on the production of film drops by bubbles bursting at the surface of seawater were parameterized earlier by Wu. More recently, comprehensive observations have been carried out ...

Jin Wu

2001-11-01T23:59:59.000Z

326

Fragmentation of Freezing Drops in Shallow Maritime Frontal Clouds  

Science Conference Proceedings (OSTI)

Images of frozen drops with pieces missing were collected on two days of airborne sampling in shallow supercooled stratiform frontal clouds in the coastal waters of Washington State. In those limited regions where ice appeared to be newly formed, ...

Arthur L. Rangno

2008-04-01T23:59:59.000Z

327

Drop-in replacement biofuels : meeting the challenge  

E-Print Network (OSTI)

This thesis presents a discussion on the challenges that must be met to fulfill the U.S. Navy's strategic imperatives for its energy vision. It provides an introduction to drop-in replacement biofuels, the options amongst ...

Bhargava, Alok (Alok Kishore)

2011-01-01T23:59:59.000Z

328

Characterizations of Aircraft Icing Environments that Include Supercooled Large Drops  

Science Conference Proceedings (OSTI)

Measurements of aircraft icing environments that include supercooled large drops (SLD) greater than 50 ?m in diameter have been made during 38 research flights. These flights were conducted during the First and Third Canadian Freezing Drizzle ...

Stewart G. Cober; George A. Isaac; J. Walter Strapp

2001-11-01T23:59:59.000Z

329

Heat transfer and pressure drop in tape generated swirl flow  

E-Print Network (OSTI)

The heat transfer and pressure drop characteristics of water in tape generated swirl flow were investigated. The test sections were electrically heated small diameter nickel tubes with tight fitting full length Inconel ...

Lopina, Robert F.

1967-01-01T23:59:59.000Z

330

Experimental study and parameterization of gas absorption by water drops  

Science Conference Proceedings (OSTI)

Mass transfer between liquid drops and a continuous gas phase occurs in a large number of industrial processes and many engineering disciplines such as chemical and nuclear engineering, atmospheric sciences, environmental engineering, and so on. Liquid-phase mass-transfer coefficients are determined for the absorption of sulfur dioxide by water drops larger than 1.1 mm in dia. A local model based on the large eddy interfacial model proposed for Fortescue and Pearson (1967) is obtained by the characteristic interfacial scaling. In particular, the agitation process of the liquid phase in the interfacial region is characterized by the interfacial liquid friction velocity. Experiments of sulfur dioxide absorption and desorption from large individually free-falling water drops are also carried out in a 5-m rain shaft under various environmental conditions. These experimental results agree well with those from the local model characterizing the interfacial process in water drops greater than 1.1 mm in dia.

Amokrane, H.; Saboni, A.; Caussade, B. (CNRS, Toulouse (France). Inst. de Mecanique des Fluides)

1994-12-01T23:59:59.000Z

331

Gas Absorption into a Moving Spheroidal Water Drop  

Science Conference Proceedings (OSTI)

Theoretical and experimental studies have been carried out to describe the absorption of sulfur dioxide by moving spheroidal water drops under transient flow conditions. These investigations allow the determination of the rate at which SO2 is ...

H. Amokrane; B. Caussade

1999-06-01T23:59:59.000Z

332

Spume Drops Produced by the Wind Tearing of Wave Crests  

Science Conference Proceedings (OSTI)

The wind tearing of breaking wave crests produces spume drops. The authors report preliminary laboratory data from direct and unambiguous observation of this process under various wind conditions using a video imaging technique. Results include ...

Magdalena Anguelova; Richard P. Barber Jr.; Jin Wu

1999-06-01T23:59:59.000Z

333

Light Scattering Characteristics and Size Distribution of ...  

Science Conference Proceedings (OSTI)

... Ian Thomas at CESARE. REFERENCES ... [19] Mulholland, GW, Hartman, AW, Hembree, GG, Marx, E., and Lettieri, T. R., "Development of a one ...

2003-12-16T23:59:59.000Z

334

New directions for gravitational wave physics via "Millikan oil drops"  

E-Print Network (OSTI)

"Millikan oil drops" are drops of superfluid helium coated with electrons, and levitated in a strong, inhomogeneous magnetic field. When the temperature of the system becomes very low compared to the cyclotron gap energy, the system remains in its quantum ground state. Two such levitated charged drops can have their charge-to-mass ratio critically adjusted so that the forces of gravity and electricity between the drops are in balance. Then it is predicted that the amount of scattered electromagnetic and gravitational radiation from the drops are equalized, along with these two kinds of forces. The cross sections for the scattering of the two kinds of radiation can become large, hard-sphere cross-sections at the first Mie resonance, due to the hard-wall boundary conditions on the surfaces of the spheres for both kinds of radiations. An efficient quantum transduction process between electromagnetic and gravitational radiation by such a pair of drops is predicted at microwave frequencies, and a Hertz-like experiment is proposed. A more practical implementation of these ideas to use pairs of levitated, charged superconducting spheres is briefly discussed.

Raymond Y. Chiao

2009-04-25T23:59:59.000Z

335

Microwave Dielectric Heating of Drops in Microfluidic Devices  

E-Print Network (OSTI)

We present a technique to locally and rapidly heat water drops in microfluidic devices with microwave dielectric heating. Water absorbs microwave power more efficiently than polymers, glass, and oils due to its permanent molecular dipole moment that has a large dielectric loss at GHz frequencies. The relevant heat capacity of the system is a single thermally isolated picoliter drop of water and this enables very fast thermal cycling. We demonstrate microwave dielectric heating in a microfluidic device that integrates a flow-focusing drop maker, drop splitters, and metal electrodes to locally deliver microwave power from an inexpensive, commercially available 3.0 GHz source and amplifier. The temperature of the drops is measured by observing the temperature dependent fluorescence intensity of cadmium selenide nanocrystals suspended in the water drops. We demonstrate characteristic heating times as short as 15 ms to steady-state temperatures as large as 30 degrees C above the base temperature of the microfluidic device. Many common biological and chemical applications require rapid and local control of temperature, such as PCR amplification of DNA, and can benefit from this new technique.

David Issadore; Katherine J. Humphry; Keith A. Brown; Lori Sandberg; David Weitz; Robert M. Westervelt

2009-01-09T23:59:59.000Z

336

Axis Ratios of Water Drops Levitated in a Vertical Wind Tunnel  

Science Conference Proceedings (OSTI)

The shapes of falling raindrops are often significantly altered by drop oscillations, complicating dual-polarization radar methods that rely on a predictable, monotonic variation of drop axis ratio ? with equivolume drop diameter d. This ...

B. K. Jones; J. R. Saylor

2009-11-01T23:59:59.000Z

337

In-service Inspection Ultrasonic Testing of Reactor Pressure Vessel Welds for Assessing Flaw Density and Size Distribution per 10 CFR 50.61a, Alternate Fracture Toughness Requirements  

SciTech Connect

Pressurized thermal shock (PTS) events are system transients in a pressurized water reactor (PWR) in which there is a rapid operating temperature cool-down that results in cold vessel temperatures with or without repressurization of the vessel. The rapid cooling of the inside surface of the reactor pressure vessel (RPV) causes thermal stresses that can combine with stresses caused by high pressure. The aggregate effect of these stresses is an increase in the potential for fracture if a pre-existing flaw is present in a material susceptible to brittle failure. The ferritic, low alloy steel of the reactor vessel beltline adjacent to the core, where neutron radiation gradually embrittles the material over the lifetime of the plant, can be susceptible to brittle fracture. The PTS rule, described in the Code of Federal Regulations, Title 10, Section 50.61 (§50.61), “Fracture Toughness Requirements for Protection against Pressurized Thermal Shock Events,” adopted on July 23, 1985, establishes screening criteria to ensure that the potential for a reactor vessel to fail due to a PTS event is deemed to be acceptably low. The U.S. Nuclear Regulatory Commission (NRC) completed a research program that concluded that the risk of through-wall cracking due to a PTS event is much lower than previously estimated. The NRC subsequently developed a rule, §50.61a, published on January 4, 2010, entitled “Alternate Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events” (75 FR 13). Use of the new rule by licensees is optional. The §50.61a rule differs from §50.61 in that it requires licensees who choose to follow this alternate method to analyze the results from periodic volumetric examinations required by the ASME Code, Section XI, Rules for Inservice Inspection (ISI) of Nuclear Power Plants. These analyses are intended to determine if the actual flaw density and size distribution in the licensee’s reactor vessel beltline welds are bounded by the flaw density and size distribution values used in the PTS technical basis. Under a contract with the NRC, Pacific Northwest National Laboratory (PNNL) has been working on a program to assess the ability of current inservice inspection (ISI)-ultrasonic testing (UT) techniques, as qualified through ASME Code, Appendix VIII, Supplements 4 and 6, to detect small fabrication or inservice-induced flaws located in RPV welds and adjacent base materials. As part of this effort, the investigators have pursued an evaluation, based on the available information, of the capability of UT to provide flaw density/distribution inputs for making RPV weld assessments in accordance with §50.61a. This paper presents the results of an evaluation of data from the 1993 Browns Ferry Nuclear Plant, Unit 3, Spirit of Appendix VIII reactor vessel examination, a comparison of the flaw density/distribution from this data with the distribution in §50.61a, possible reasons for differences, and plans and recommendations for further work in this area.

Sullivan, Edmund J.; Anderson, Michael T.; Norris, Wallace

2012-09-17T23:59:59.000Z

338

Energy Innovator Drops Costs for Titanium Metalwork | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Innovator Drops Costs for Titanium Metalwork Innovator Drops Costs for Titanium Metalwork Energy Innovator Drops Costs for Titanium Metalwork March 13, 2012 - 12:42pm Addthis Michael Hess Michael Hess Former Digital Communications Specialist, Office of Public Affairs What are the key facts? Iowa Powder Atomization Technology is one of 36 companies that licensed technology under an agreement with the National Lab as part of the America's Next Top Energy Innovator program. Titanium is the stuff aircrafts are made of, at least the important parts. It's an obvious material choice for aircraft engines and airframes with its high strength-to-weight ratio and resistance to corrosion. However, shaping the metal into complex shapes can be expensive. Using a heavier, easier-to-craft metal can be just as expensive because adding weight to an

339

EA-1933: Yakama Nation Drop 4 Hydropower Project, Yakama Nation  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

933: Yakama Nation Drop 4 Hydropower Project, Yakama Nation 933: Yakama Nation Drop 4 Hydropower Project, Yakama Nation Reservation, WA EA-1933: Yakama Nation Drop 4 Hydropower Project, Yakama Nation Reservation, WA SUMMARY DOE is a cooperating agency with the Department of the Interior's Bureau of Indian Affairs as a lead agency for the preparation of an EA to evaluate the potential environmental impacts of a proposal by the Confederated Tribes and Bands of the Yakama Nation Department of Natural Resources to install an inline turbine on the Wapato Irrigation Project (WIP) Main Canal to generate approximately one megawatt of supplemental hydroelectric power. The Main Canal is a non-fish bearing irrigation canal within the WIP water conveyance system. The project site is located two miles southwest of Harrah, Washington.

340

Frictionally induced ignition processes in drop and skid tests  

SciTech Connect

The standard LANL/Pantex drop and skid tests rely on subjective assessment of reaction violence to quantify the response of the charge, and completely miss nonpropagating hot-spot ignition sites. Additionally, large variations in test results have been observed, which we propose is due to a misunderstanding of the basic physical processes that lead to threshold ignition in these tests. The tests have been redesigned to provide control of these mechanisms and to permit direct observation of hot spots at the impact site, allowing us to follow the progression of the outcome as the drop height and ignition source density are varied. The results confirm that frictional interactions between high-melting-point solids are the dominant ignition mechanism, not just at the threshold, but in fact at all realistic drop heights.

Dickson, Peter [Los Alamos National Laboratory; Parker, Gary [Los Alamos National Laboratory; Novak, Alan [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Heat transfer and pressure drop in hexagonal ducts with surface dimples  

SciTech Connect

Measurements of detailed Nusselt number (Nu) distributions and pressure drop coefficients (f) for four hexagonal ducts with smooth and dimpled walls are performed to comparatively examine the thermal performances of three sets of dimpled walls with concave-concave, convex-convex and concave-convex configurations at Reynolds numbers (Re) in the range of 900-30,000. A set of selected experimental data illustrates the influences of dimple configuration and Re on the detailed Nu distributions, the area-averaged Nu over developed flow region (Nu-bar) and the pressure drop coefficients. Relative enhancements of Nu and f from the smooth-walled references (Nu{sub {infinity}} and f{sub {infinity}}) along with the thermal performance factor ({eta}) defined as (Nu-bar/Nu{sub {infinity}})/(f/f{sub {infinity}}){sup 1/3} are examined. Nu-bar and f correlations are individually obtained for each tested hexagonal duct using Re as the controlling parameter. (author)

Chang, S.W. [Thermal Fluids Laboratory, National Kaohsiung Marine University, No. 142, Haijhuan Road, Nanzih District, Kaohsiung City 81143 (China); Chiang, K.F. [Thermal Dissipation Department, AVC International Company (China); Chou, T.C. [Department of Marine Engineering, National Kaohsiung Marine University (China)

2010-11-15T23:59:59.000Z

342

Drops of Energy Conserving Urban Water in California  

E-Print Network (OSTI)

in California to Reduce Greenhouse Gas Emissions improvements to their energy usage through efficiency measuresDrops of Energy Conserving Urban Water in California to Reduce Greenhouse Gas Emissions May 2011 School of Law's Center for Law, Energy & the Environment and UCLA School of Law's Environmental Law

Kammen, Daniel M.

343

Delamination initiation in postbuckled dropped-ply laminates  

Science Conference Proceedings (OSTI)

The compression strength of dropped-ply, graphite-epoxy laminated plates for the delamination mode of failure is studied by analysis and corroborated with experiments. The nonlinear response of the test specimens is modeled by a geometrically nonlinear finite-element analysis. The methodology for predicting delamination is based on a quadratic interlaminar stress criterion evaluated at a characteristic distance from the ply drop-off. The details of the complex state of stress in the region of the thickness discontinuity are studied using three-dimensional solid elements, while the uniform sections of the plate are modeled with quadrilateral shell elements. A geometrically nonlinear transition element was developed to couple the shell elements to the solid elements. Uniaxial compression testing of dropped-ply, graphite-epoxy laminated plates confirmed that delamination among the interfaces above and/or below the dropped plies is a common mode of failure initiation. The compression strength of specimens exhibiting a linear response is greater than the compression strength of specimens with the same layup exhibiting geometrically nonlinear response.

Davila, C.G.

1991-01-01T23:59:59.000Z

344

Transonic Pressure-- Sensing Studies Using Drop Test Vehicles  

SciTech Connect

Free-flight drop vehicle tests have been made to investigate devices for measuring ambient pressure in the vicinity of a high-fineness-ratio weapon shape throughout the transonic speed range. Various types of nose probes and trailing probes were tested.

Pepper, W.B., Jr. [Organization 5141

1954-05-01T23:59:59.000Z

345

Collision Rate of Small Graupel and Water Drops  

Science Conference Proceedings (OSTI)

An approach permitting one to calculate the collision efficiency and the collision kernel of spherical particles of different densities for Reynolds numbers up to 100 (300-?m-radius drops, or 700-?m-radius graupel) is presented. It is used for ...

A. Khain; M. Pinsky; M. Shapiro; A. Pokrovsky

2001-09-01T23:59:59.000Z

346

PRESSURE DROP EVALUATION OF THE HYDROGEN CIRCULATION SYSTEM FOR JSNS  

SciTech Connect

In J-PARC, an intense spallation neutron source (JSNS) driven by a proton beam of 1 MW has selected supercritical hydrogen with a temperature of around 20 K and the pressure of 1.5 MPa as a moderator material. A hydrogen-circulation system, which consists of two pumps, an ortho-para hydrogen converter, a heater, an accumulator and a helium-hydrogen heat exchanger, has been designed to provide supercritical hydrogen to the moderators and remove the nuclear heating there. A hydrogen-circulation system is cooled through the heat exchanger by a helium refrigerator with the refrigeration power of 6.45 kW at 15.5 K. It is important for the cooling design of the hydrogen-circulation system to understand the pressure drops through the equipments. In this work, the pressure drop through each component was analyzed by using a CFD code, STAR-CD. The correlation of the pressure drops through the components that can describe the analytical results within 14% differences has been derived. It is confirmed that the pressure drop in the hydrogen circulation system would be estimated to be 37 kPa for the circulation flow rate of 160 g/s by using the correlations derived here, and is sufficiently lower than the allowable pump head of 100 kPa.

Tatsumoto, H.; Aso, T.; Ohtsu, K.; Kato, T.; Futakawa, M. [J-PARC Center, Japan Atomic Energy Agency, Tokai, Ibaraki, 319-1195 (Japan)

2010-04-09T23:59:59.000Z

347

Two phase pressure drop in inclined and vertical pipes  

E-Print Network (OSTI)

A method of calculating the pressure drop in inclined and vertical oil-gas wells is proposed. The data used to establish the method is from a variety of sources but is largely from air and water flowing in systems close ...

Griffith, P.

1973-01-01T23:59:59.000Z

348

Manhattan Project: Order to Drop the Atomic Bomb  

Office of Scientific and Technical Information (OSTI)

ORDER TO DROP THE ATOMIC BOMB Handy to Spaatz, National Archives (July 25, 1945) Resources > Library The document below is the order to attack Japanese cities with atomic bombs. In it, the Acting Army Chief of Staff, Thomas Handy, orders Commanding General Carl Spaatz, Army Strategic Air Forces, to "deliver [the] first special bomb as soon as weather will permit . . . after about 3 August 1945." The target list: "Hiroshima, Kokura, Niigata, and Nagasaki." Further attacks were also authorized: "additional bombs will be delivered on the above targets as soon as made ready." Handy was the acting chief of staff because George Marshall was with President Harry S. Truman at the Potsdam Conference. The letter explicitly notes that this order was approved by Marshall and Secretary of War Henry Stimson. Truman, of course, provided the ultimate authorization for dropping the bomb.

349

Drop Tests for the 6M Specification Package Closure Investigation  

SciTech Connect

Results of tests of drum-type RAM packages employing conventional clamp-ring closures have caused concern within the DOE Complex over the Department of Transportation 6M Specification Package. To clarify these issues, the Savannah River Site's Radioactive Material Packaging Technology Group was commissioned to conduct a series of tests to determine the response of the clamp-ring closure to the regulatory Hypothetical Accident Condition drop tests, for packages at maximum allowable weight, 640 lb. Additionally, three enhanced closure designs were also tested: the Clamshell, plywood disk reinforcement, and J-Clip. The results of the tests showed that the standard closure was unable to retain its lid for both Center-of-Gravity-Over-Corner and Shallow-Angle cases, for the standard package, at its maximum allowed weight. Similar results were found for packages dropped from a reduced height. The Clamshell design provided the best performance of the enhanced closures.

Smith, A.C.

2003-10-02T23:59:59.000Z

350

Sliding drops across alternating hydrophobic and hydrophilic stripes  

E-Print Network (OSTI)

We perform a joint numerical and experimental study to sistematically characterize the motion of drops sliding over a periodic array of alternating hydrophobic and hydrophilic stripes with large wettability contrast, and typical width of hundreds of $\\mu \\textrm{m}$. The fraction of the hydrophobic stripes has been varied from about 20% to 80%. The effects of the heterogeneous patterning can be described by a renormalized value of the critical Bond number, i.e. the critical dimensionless force needed to depin the drop before it starts to move. Close to the critical Bond number we observe a jerkily motion characterized by an evident stick-slip dynamics. As a result, dissipation is strongly localized in time, and the mean velocity of the drops can easily decrease by an order of magnitude compared to the sliding on homogeneous surface. Lattice Boltzmann (LB) numerical simulations are crucial for disclosing to what extent the sliding dynamics can be deduced from the computed balance of capillary, viscous and body forces at varying the Bond number, the surface composition and the liquid viscosity. Away from the critical Bond number, we characterize both experimentally and numerically the dissipation inside the droplet by studying the relation between the average velocity and the applied volume forces.

M. Sbragaglia; L. Biferale; G. Amati; S. Varagnolo; D. Ferraro; G. Mistura; M. Pierno

2013-10-16T23:59:59.000Z

351

Syracuse Univesity Test Report On Uptake Factor Resulting From A Dropped Storage Container - Phase II  

Science Conference Proceedings (OSTI)

Under certain circumstances, powder from an accidently dropped container can become airborne and inhaled by people nearby such as those who are moving the containers. The inhaled fine particles can deposit on respiratory tracts and lungs, causing asthma, lung cancer, and other acute respiratory illnesses and chronic symptoms. The objective of this study was to develop a standard procedure to measure the airborne concentrations of different size particles within the vicinity of a dropped container where a significant portion of the contained powder is ejected. Tungsten oxide (WO{sub 3}) was selected in this study to represent relatively heavy powders (7.16 g/cm3 specific gravity for WO{sub 3}). A typical can with the outer dimensions of 4.25” diameter and 4.875” tall was used as the container. The powder was dropped in two different configurations: 1) contained within a can covered by a lid that has a 0.25” diameter hole, and 2) contained within a can without a lid. The packing volume of the powder was 51.4 in3 (842.7 cm{sup 3}) and the target mass was 1936 g. The tests were carried out in a full-scale stainless steel environmental chamber with an interior volume of 852 ft3 (24.1 m3). The chamber system includes an internal recirculation loop with a rectangular air diffuser and 10 variable frequency drive fans to provide a typical room air recirculation flow pattern. Two air filters were installed in the chamber air supply duct and return duct to achieve the required low background particle concentration. The initial chamber air conditions were set at 70°F (± 5°F) and 50% (± 10%) RH. A supporting frame and releasing device were designed and built to trigger consistently the dropping of the can. The particle sampling inlet was placed 5 ft above the floor and 6 inches laterally away from the can’s falling path. Concentrations of particles between 0.5 ?m and 20 ?m were recorded in units of mass and number of particles per unit volume. The data acquisition rate was once every 2 seconds during the first 2 hours. A test procedure was developed and verified. A total of thirty two drop tests were performed, eight in Phase I and twenty four in Phase II, covering variations in dropping height (8 ft or 4 ft from the floor), room air movement (0.25-0.30 m/s or 0.10-0.15 m/s near the ceiling), landing scenario (on a flat plate or a block), and lid condition (¼” lid hole or no lid). There were ten tests with flat plate and ¼” lid hole, ten tests with flat plate no lid and twelve tests with block no lid.

Gao, Zhi; Zhang, Jianshun S.

2012-01-01T23:59:59.000Z

352

Physical and Chemical Characterization of Kuwaiti Atmospheric Dust and Synthetic Dusts: Effects on the Pressure Drop and Fractional Efficiency of HEPA Filters  

E-Print Network (OSTI)

The importance of clean air to the indoor air quality affecting the well-being of human occupants and rising energy consumption has highlighted the critical role of air filter performance. Actual performance of air filters installed in air handling units in Kuwait tends to deviate from the performance predicted by laboratory results. Therefore, accurate filter performance prediction is important to estimate filter lifetime, and to reduce energy and maintenance operating costs. To ensure appropriate filter selection for a specific application, particulate contaminants existing in the Kuwaiti atmospheric dust were identified and characterized both physically and chemically and compared to the synthetic dust used in laboratories. This paper compares the physical and chemical characterization Kuwaiti atmospheric dust with the available commercial synthetic dusts. It also tests full scale HEPA pleated V-shaped filters used in Heating Ventilation and Air Conditioning (HVAC) and gas turbine applications to study the effect of different synthetic dust types and their particle size distributions on the pressure drop and fractional efficiency using DEHS testing according to DIN 1822.

Al-Attar, I.; Wakeman, R. J.; Tarleton, E. S.; Husain, A.

2010-01-01T23:59:59.000Z

353

Growth Of Cloud Drops by Condensation: A Criticism of Currently Accepted Theory and a New Approach  

Science Conference Proceedings (OSTI)

The currently accepted theory of the growth of cloud drops by condensation employs an equation for the rate of increase of drop mass and an equation for the supersaturation. The latter equation gives the average supersaturation over a large ...

R. C. Srivastava

1989-04-01T23:59:59.000Z

354

Drop Shapes, Model Comparisons, and Calculations of Polarimetric Radar Parameters in Rain  

Science Conference Proceedings (OSTI)

Drop shapes derived from a previously conducted artificial rain experiment using a two-dimensional video disdrometer (2DVD) are presented. The experiment involved drops falling over a distance of 80 m to achieve their terminal velocities as well ...

M. Thurai; G. J. Huang; V. N. Bringi; W. L. Randeu; M. Schönhuber

2007-06-01T23:59:59.000Z

355

Collisions between Small Precipitation Drops. Part I: Laboratory Measurements of Bounce, Coalescence, and Temporary Coalescence  

Science Conference Proceedings (OSTI)

Self-collection efficiencies were measured for isolated drop pairs failing at terminal velocity using orthogonal cameras to obtain the horizontal offset of the drops before collision and the collision outcome. Data were obtained on four different ...

Harry T. Ochs III; Kenneth V. Beard; Robert R. Czys; Neil F. Laird; Daniel E. Schaufelberger; Donna J. Holdridge

1995-06-01T23:59:59.000Z

356

Effects of Relative Humidity on the Coalescence of Small Precipitation Drops in Free Fall  

Science Conference Proceedings (OSTI)

Observations of the effects of relative humidity on coalescence are limited to studies using supported drops or streams of drops, and the results are contradictory. In this paper, findings are presented on the effect of high and low relative ...

Harry T. Ochs III; Kenneth V. Beard; Neil F. Laird; Donna J. Holdridge; Daniel E. Schaufelberger

1995-11-01T23:59:59.000Z

357

Laboratory and In Situ Observation of Deposition Growth of Frozen Drops  

Science Conference Proceedings (OSTI)

The water vapor deposition growth of frozen drops with diameter greater than 100 ?m has been studied in a thermal diffusion chamber. For varying periods of time, it was found that frozen drops experience spherical growth. The characteristic time ...

Alexei V. Korolev; Matthew P. Bailey; John Hallett; George A. Isaac

2004-04-01T23:59:59.000Z

358

The Influence of Charge on the Coalescence of Water Drops in Free Fall  

Science Conference Proceedings (OSTI)

The influence of charge on coalescence was determined in the laboratory for isolated pairs of 340 and 190 ?m water drops failing freely at terminal velocity. A microcomputer-controlled apparatus was used to produce collisions. Drop charges were ...

Robert R. Czys; Harry T. Ochs III

1988-11-01T23:59:59.000Z

359

A Wind Tunnel Study of Turbulence Effects on the Scavenging of Aerosol Particles by Water Drops  

Science Conference Proceedings (OSTI)

Laboratory experiments are described where the effects of turbulence on the impaction scavenging of aerosol particles by water drops were investigated. During the experiments the drops were freely suspended at their terminal velocities in the ...

O. Vohl; S. K. Mitra; K. Diehl; G. Huber; S. C. Wurzler; K-L. Kratz; H. R. Pruppacher

2001-10-01T23:59:59.000Z

360

Optimal Porosity Distribution for Minimized Ohmic Drop across a Porous Electrode  

E-Print Network (OSTI)

This paper considers the design of spatially varying porosity profiles in next-generation electrodes based on simultaneous optimization of a porous-electrode model. Model-based optimal design (not including the solid-phase ...

Braatz, Richard D.

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Friction pressure drop measurements and flow distribution analysis for LEU conversion study of MIT Research Reactor  

E-Print Network (OSTI)

The MIT Nuclear Research Reactor (MITR) is the only research reactor in the United States that utilizes plate-type fuel elements with longitudinal fins to augment heat transfer. Recent studies on the conversion to low-enriched ...

Wong, Susanna Yuen-Ting

2008-01-01T23:59:59.000Z

362

Piezoelectric Drop-on-Demand Inkjet Printing of Rat Fibroblast Cells: Survivability Study and Pattern Printing  

E-Print Network (OSTI)

A novel piezoelectric, drop-on-demand (DOD) inkjet system has been developed and used to print L929 rat fibroblast cells. We investigate the survivability of the cells subjected to the large stresses during the printing process. These stresses are varied by changing the diameter of the orifice (36 to 119 microns) through which the cells are dispensed, as well as changing the electrical pulse used to drive the piezoelectric element. It is shown that for the smallest 36 microns diameter orifice, cell survival rates fall from 95% to approximately 76% when the ejection velocity is increased from 2 to 16 m/s. This decrease in survival rates is less significant when the larger orifice diameters of 81 microns and 119 microns are used. Analysis shows that there is a clear inverse relationship between cell survival rates and the mean shear rates during drop formation. By using the same printing set-up, fibroblast cells are printed onto alginate and collagen into patterns. Printed cells are cultured over a period of days to verify their long-term viability. Fibroblasts printed onto the collagen are found to successfully adhere, spread and proliferate, subsequently forming a denser patterns after 5 days in culture. Cell agglomeration is found to affect the printing performance, especially for the printhead with the smallest orifice, leading to frequent clogging of the nozzle. We also study the number of cells in each droplet, when printed under optimal conditions. The probability density of this number follows a binomial distribution, which consistent with a uniform distribution of cells in the medium and within the printhead.

Er Qiang Li; Eng Khoon Tan; Sigurdur Tryggvi Thoroddsen

2013-10-02T23:59:59.000Z

363

Potential hydroelectric power Mora Canal Drop. Final report  

DOE Green Energy (OSTI)

The feasibility of installing a hydroelectric power plant on the Mora Canal Drop site in Idaho was studied. It was recommended that a 1900 kW unit be installed to generate 8,113,000 kWh per year. The project should cost approximately $1.8 million. The generating cost would be between 20.3 and 22.2 mills/kWh. A local utility has offered to buy all power produced at 26 mills/kWh. No adverse environment, safety, or socio-economic effects are foreseen. (LCL)

Willer, D.C.

1978-12-01T23:59:59.000Z

364

High speed shadowgraphy for the study of liquid drops  

E-Print Network (OSTI)

: Creating Panoramic and Object Images, Library of Congress, ISBN: 978-0-165-34223-8, p 38. Hutchings I M, Martin G D and Hoath S D, (2007) Journal of Imaging Science and Technology 51(5), 438-444. Jones A R, (1977) Progress in Energy and Combustion... High speed shadowgraphy for the study of liquid drops José Rafael Castrejón-Pita, Rafael Castrejón-García§, Ian Hutchings Department of Engineering, University of Cambridge, CB3 0FS, 17 Charles Babbage Road, Cambridge, United Kingdom...

Castrejon-Pita, J.R.; Castrejon-Garcia, R.; Hutchings, I.M.

2012-01-01T23:59:59.000Z

365

Conditioning analysis of incomplete Cholesky factorizations with orthogonal dropping  

SciTech Connect

The analysis of preconditioners based on incomplete Cholesky factorization in which the neglected (dropped) components are orthogonal to the approximations being kept is presented. General estimate for the condition number of the preconditioned system is given which only depends on the accuracy of individual approximations. The estimate is further improved if, for instance, only the newly computed rows of the factor are modified during each approximation step. In this latter case it is further shown to be sharp. The analysis is illustrated with some existing factorizations in the context of discretized elliptic partial differential equations.

Napov, Artem

2012-03-16T23:59:59.000Z

366

1999 Commercial Buildings Characteristics--Building Size  

U.S. Energy Information Administration (EIA) Indexed Site

Size of Buildings Size of Buildings Size of Buildings The 1999 CBECS estimated that 2,348,000 commercial buildings, or just over half (50.4 percent) of total buildings, were found in the smallest building size category (1,001 to 5,000 square feet) (Figure 1). Only 7,000 buildings occupied the largest size category (over 500,000 square feet). Detailed tables Figure 1. Distribution of Buildings by Size of Building, 1999 Figure 1. Distribution of Buildings by Size of Building, 1999. If having trouble viewing this page, please contact the National Energy Information Center at (202) 586-8800. Energy Information Administration Commercial Buildings Energy Consumption Survey The middle size categories (10,001 to 100,000 square feet) had relatively more floorspace per category than smaller or larger size categories (Figure 2). The greatest amount of floorspace, about 11,153,000 square feet (or 17 percent of total floorspace) was found in the 10,001 to 25,000 square feet category. Figure 2. Distribution of Floorspace by Size of Building, 1999

367

Drop Dynamics and Speciation in Isolation of Metals from Liquid Wastes by Reactive Scavenging  

SciTech Connect

Computational and experimental studies of the motion and dynamics of liquid drops in gas flows were conducted with relevance to reactive scavenging of metals from atomized liquid waste. Navier-Stoke's computations of deformable drops revealed a range of conditions from which prolate drops are expected, and showed how frajectiones of deformable drops undergoing deceleration can be computed. Experimental work focused on development of emission fluorescence, and scattering diagnostics. The instrument developed was used to image drop shapes, soot, and nonaxisymmetric departures from steady flow in a 22kw combustor

Arne J. Pearlstein; Alexander Scheeline

2002-08-30T23:59:59.000Z

368

Drop Tests for the 6M Specification Package Closure Investigation  

SciTech Connect

Results of tests of drum-type RAM packages employing conventional clamp-ring closures have caused concern over the DOT 6M Specification Package. To clarify these issues, a series of tests were performed to determine the response of the clamp-ring closure to the regulatory Hypothetical Accident Condition (9m) drop tests, for packages at maximum allowable weight. Three enhanced closure designs were also tested: the Clamshell, plywood disk reinforcement, and J-Clip. The results of the tests showed that the standard closure was unable to retain the top for both Center-of-Gravity-Over-Corner and Shallow Angle cases, for the standard package, at its maximum allowed weight. Similar results were found for packages dropped from a reduced height. The Clamshell design provided the best performance of the enhanced closures. It was concluded that the closure ring design employed on the 6M is inadequate to retain the top during the regulatory test sequence, for packages at the maximum allowed weight. For large heavy packages, the Center-of-Gravity- Over-Corner case is more challenging than the Shallow Angle case. The Clamshell design securely retained the top for all HAC test cases, and prevented formation of any opening which could compromise fire test performance.

SMITH, AC

2004-04-30T23:59:59.000Z

369

Thermo-Electro-Mechanical Investigation of Voltage Drop on Anode ...  

Science Conference Proceedings (OSTI)

Cryoscopic Data for Hall-Héroult Bath Containing Magnesium Fluoride, Calcium Fluoride, Potassium Cryolite, and Sodium Chloride · Current Distribution and ...

370

Cobra-IE Evaluation by Simulation of the NUPEC BWR Full-Size Fine-Mesh Bundle Test (BFBT)  

Science Conference Proceedings (OSTI)

The COBRA-IE computer code is a thermal-hydraulic subchannel analysis program capable of simulating phenomena present in both PWRs and BWRs. As part of ongoing COBRA-IE assessment efforts, the code has been evaluated against experimental data from the NUPEC BWR Full-Size Fine-Mesh Bundle Tests (BFBT). The BFBT experiments utilized an 8 x 8 rod bundle to simulate BWR operating conditions and power profiles, providing an excellent database for investigation of the capabilities of the code. Benchmarks performed included steady-state and transient void distribution, single-phase and two-phase pressure drop, and steady-state and transient critical power measurements. COBRA-IE effectively captured the trends seen in the experimental data with acceptable prediction error. Future sensitivity studies are planned to investigate the effects of enabling and/or modifying optional code models dealing with void drift, turbulent mixing, rewetting, and CHF.

Burns, C. J. and Aumiler, D. L.

2006-04-26T23:59:59.000Z

371

Airflow and Water-Drop Trajectories at Instrument Sampling Points around the Beechcraft King Air and Lockheed Electra  

Science Conference Proceedings (OSTI)

Due to distortion of airflow streamlines, flow velocities and droplet size distributions measured around a moving aircraft can differ from freestream conditions. This can complicate measurements made from aircraft platforms. Potential flow ...

Cynthia H. Twohy; Diana Rogers

1993-08-01T23:59:59.000Z

372

Evaluation and performance prediction of cooling tower spray zones.  

E-Print Network (OSTI)

??Cooling tower spray nozzle performance characteristics such as the water distribution onto the fill material, air side pressure drop, pump head, drop size distribution and… (more)

Viljoen, D. J.

2006-01-01T23:59:59.000Z

373

Total number of longwall faces drops below 50  

Science Conference Proceedings (OSTI)

For the first time since Coal Age began its annual Longwall Census the number of faces has dropped below 50. A total of five mines operate two longwall faces. CONSOL Energy remains the leader with 12 faces. Arch Coal operates five longwall mines; Robert E. Murray owns five longwall mines. West Virginia has 13 longwalls, followed by Pennsylvania (8), Utah (6) and Alabama (6). A detailed table gives for each longwall installation, the ownership, seam height, cutting height, panel width and length, overburden, number of gate entries, depth of cut, model of equipment used (shearer, haulage system, roof support, face conveyor, stage loader, crusher, electrical controls and voltage to face). 2 tabs., 1 photo.

Fiscor, S.

2009-02-15T23:59:59.000Z

374

Drop Tests of 325 Pound 6M Specification Packages  

Science Conference Proceedings (OSTI)

Testing of 6M specification packages, performed in response to concerns over the integrity of the clamp-ring closure, showed that the clamp-ring was unable to retain the top in thirty foot drop tests of packages having the maximum allowed weight (290 kg or 640 lb). To determine if the clamp-ring closure was adequate for packages with lower contents weight, a series of tests were performed on packages weighing 147 kg (325 lb) at a range of impact angles. The results showed that the standard clamp-ring closure was unable to retain the top in tests of standard 6M packages weighing 147 kg (325 lb). A test employing a plywood disk enhanced closure with impact at 6.5 degrees retained its top successfully.

SMITH, AC

2004-04-30T23:59:59.000Z

375

Analyzing the BWR rod drop accident in high-burnup cores  

SciTech Connect

This study was undertaken for the US Nuclear Regulatory Commission to determine the fuel enthalpy during a rod drop accident (RDA) for cores with high burnup fuel. The calculations were done with the RAMONA-4B code which models the core with 3-dimensional neutron kinetics and multiple parallel coolant channels. The calculations were done with a model for a BWR/4 with fuel bundles having burnups up to 30 GWd/t and also with a model with bundle burnups to 60 GWd/t. This paper also discusses potential sources of uncertainty in calculations with high burnup fuel. One source is the ``rim`` effect which is the extra large peaking of the power distribution at the surface of the pellet. This increases the uncertainty in reactor physics and heat conduction models that assume that the energy deposition has a less peaked spatial distribution. Two other sources of uncertainty are the result of the delayed neutron fraction decreasing with burnup and the positive moderator temperature feedback increasing with burnup. Since these effects tend to increase the severity of the event, an RDA calculation for high burnup fuel will underpredict the fuel enthalpy if the effects are not properly taken into account. Other sources of uncertainty that are important come from the initial conditions chosen for the RDA. This includes the initial control rod pattern as well as the initial thermal-hydraulic conditions.

Diamond, D.J.; Neymotin, L.; Kohut, P.

1995-08-01T23:59:59.000Z

376

State Policy: One Size Doesnt Fit All  

Wind Powering America (EERE)

Policy: One Size Doesn't Fit All Larry Flowers Deputy Director, Distributed and Community Wind American Wind Energy Association lflowers@awea.org www.awea.orgcommunitywind...

377

Cat heart Size  

NLE Websites -- All DOE Office Websites (Extended Search)

heart Size Name: Iris Status: student Grade: K-3 Location: OR Country: USA Date: NA Question: Can you tell me the size of a cats heart? Replies: Iris A cat's heart is about the...

378

Cat heart Size  

NLE Websites -- All DOE Office Websites (Extended Search)

Cat heart Size Name: Rebecca Status: student Grade: 6-8 Location: FL Country: USA Date: Spring 2011 Question: What is the average size of a cat's heart? Replies: Hi Rebecca, That...

379

Hopper Job Size Charts  

NLE Websites -- All DOE Office Websites (Extended Search)

charts shows the fraction of hours used on Hopper in each of 5 job-core-size bins. 2012 Usage by Job Size Chart 2011 . This chart shows the fraction of hours used on Hopper by jobs...

380

Errors and Uncertainties in Microwave Link Rainfall Estimation Explored Using Drop Size Measurements and High-Resolution Radar Data  

Science Conference Proceedings (OSTI)

Microwave links can be used for the estimation of path-averaged rainfall by using either the path-integrated attenuation or the difference in attenuation of two signals with different frequencies and/or polarizations. Link signals have been ...

Hidde Leijnse; Remko Uijlenhoet; Alexis Berne

2010-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

A New Optical Instrument for Simultaneous Measurement of Raindrop Diameter and Fall Speed Distributions  

Science Conference Proceedings (OSTI)

This paper presents a recently developed optical spectro-pluviometer. The principle of the device is based upon the optical occultation of an infrared light beam by falling drops. This allows the retrieval of raindrop-size and velocity ...

Danièle Hauser; Paul Amayenc; Bernard Nutten; Philippe Waldteufel

1984-09-01T23:59:59.000Z

382

Anisotropic wetting and de-wetting of drops on substrates patterned with polygonal posts  

E-Print Network (OSTI)

We present results showing how water drops, produced by ink-jet printing, spread on surfaces patterned with lattices of diamond or triangular posts. Considering post widths typically ~7 m and lattice spacings between 15-40 m, we observe drop shapes with 3,4 and 6-fold symmetry, depending on both the symmetry of the lattice and the shape of the posts. This is a result of the different mechanisms of interface pinning and depinning which depend on the direction of the contact line motion with respect to the post shape. Lattice Boltzmann simulations are used to describe these mechanisms in detail for triangular posts. We also follow the motion of the contact line as the drops evaporate showing that they tend to return to their original shape. To explain this we show that the easy direction for movement is the same for spreading and drying drops. We compare the behaviour of small drops with that of larger drops created by jetting several drops at the same position. We find that the contact line motion is unexpectedly insensitive to drop volume, even when a spherical cap of fluid forms above the posts. The findings are relevant to microfluidic applications and to the control of drop shapes in ink-jet printing.

Robert J. Vrancken; Matthew L. Blow; Halim Kusumaatmaja; Ko Hermans; An M. Prenen; Cees W. M. Bastiaansen; Dirk J. Broer; Julia M. Yeomans

2012-10-23T23:59:59.000Z

383

Design of shell and tube heat exchanger using specified pressure drop.  

E-Print Network (OSTI)

??The pressure drops used in heat exchange of shell and tube type, the situations are particular and put ahead of the design exercise. In such… (more)

Bilimoria, Vimalkumar B.

2010-01-01T23:59:59.000Z

384

Co-gasification of biomass with coal and oil sands coke in a drop tube furnace.  

E-Print Network (OSTI)

??Chars were obtained from individual fuels and blends with different blend ratios of coal, coke and biomass in Drop Tube Furnace at different temperatures. Based… (more)

Gao, Chen

2010-01-01T23:59:59.000Z

385

SIZE AND SURFACE AREA OF ICY DUST AGGREGATES AFTER A HEATING EVENT AT A PROTOPLANETARY NEBULA  

Science Conference Proceedings (OSTI)

The activity of a young star rises abruptly during an FU Orionis outburst. This event causes a temporary temperature increase in the protoplanetary nebula. H{sub 2}O icy grains are sublimated by this event, and silicate cores embedded inside the ice are ejected. During the high-temperature phase, the silicate grains coagulate to form silicate core aggregates. After the heating event, the temperature drops, and the ice recondenses onto the aggregates. I determined numerically the size distribution of the ice-covered aggregates. The size of the aggregates exceeds 10 {mu}m around the snow line. Because of the migration of the ice to large aggregates, only a small fraction of the silicate core aggregate is covered with H{sub 2}O ice. After the heating event, the surface of an ice-covered aggregate is totally covered by silicate core aggregates. This might reduce the fragmentation velocity of aggregates when they collide. It is possible that the covering silicate cores shield the UV radiation field which induces photodissociation of H{sub 2}O ice. This effect may cause the shortage of cold H{sub 2}O vapor observed by Herschel.

Sirono, Sin-iti [Earth and Environmental Sciences, Graduate School of Environmental Studies, Nagoya University, Nagoya 464-8601 (Japan)] [Earth and Environmental Sciences, Graduate School of Environmental Studies, Nagoya University, Nagoya 464-8601 (Japan)

2013-03-01T23:59:59.000Z

386

Stability issues in IC Low Drop Out voltage regulators  

E-Print Network (OSTI)

Performance issues of IC Low Drop Out (LDO) voltage regulators, with specific reference to stability, are discussed in this thesis. Evaluation of existing frequency compensation schemes and their performances across operating loads is presented. The problem of instability of the LDO voltage regulator at low Electo Static Resistance (ESR) of the load capacitors and the consequences of this problem are highlighted. As a solution to some of the discussed problems, an alternate LDO voltage regulator topology that is stable with low Electro Static Resistance (ESR) capacitive loads is presented. The proposed scheme, instead of relying on the zero generated by the load capacitor and its ESR combination for stability, generates a zero internally. The LDO voltage regulator is implemented and fabricated in AMI 0.5mm CMOS technology through MOSIS service. It is demonstrated that this scheme realizes robust frequency compensation, facilitates use of Multi Layer Ceramic Capacitors (MLCC) for load of LDO regulators, and improves transient response and noise performance. Test results from the prototype provide an evaluation of the most important parameters of the regulator: ground current, load regulation, line regulation, output noise and start-up time.

Chava, Krishna Chaitanya

2002-01-01T23:59:59.000Z

387

Free energy of colloidal particles at the surface of sessile drops  

E-Print Network (OSTI)

The influence of finite system size on the free energy of a spherical particle floating at the surface of a sessile droplet is studied both analytically and numerically. In the special case that the contact angle at the substrate equals $\\pi/2$ a capillary analogue of the method of images is applied in order to calculate small deformations of the droplet shape if an external force is applied to the particle. The type of boundary conditions for the droplet shape at the substrate determines the sign of the capillary monopole associated with the image particle. Therefore, the free energy of the particle, which is proportional to the interaction energy of the original particle with its image, can be of either sign, too. The analytic solutions, given by the Green's function of the capillary equation, are constructed such that the condition of the forces acting on the droplet being balanced and of the volume constraint are fulfilled. Besides the known phenomena of attraction of a particle to a free contact line and repulsion from a pinned one, we observe a local free energy minimum for the particle being located at the drop apex or at an intermediate angle, respectively. This peculiarity can be traced back to a non-monotonic behavior of the Green's function, which reflects the interplay between the deformations of the droplet shape and the volume constraint.

J. Guzowski; M. Tasinkevych; S. Dietrich

2010-07-14T23:59:59.000Z

388

We encountered a particularly intriguing imita-tion bird-dropping on the dorsal wing surface  

E-Print Network (OSTI)

to have false images of flies on its wings. It may be our imagination, but don't those red compound eyesWe encountered a particularly intriguing imita- tion bird-dropping on the dorsal wing surface the imitation bird dropping and odor was accom- panied by a most extraordinary wing pattern. To our astonishment

Monteiro, Antónia

389

Gas Scavenging of Soluble and Insoluble Organic Vapors by Levitated Water Drops  

Science Conference Proceedings (OSTI)

Three-millimeter-diameter drops of water were levitated with a standing acoustic wave centered in the jet of a small wind tunnel and the volume changes as the drop evaporates in the presence of 1-propanol vapor were measured. The results are ...

Mark Seaver; Amy Barrett

1994-07-01T23:59:59.000Z

390

Influence of voltage drop to electric drive with induction motor and voltage sourced inverter  

Science Conference Proceedings (OSTI)

This paper solves problematic of immunity from the voltage drop of the power supply of the electric drive with induction motor with Voltage-Fed inverter. There are reflected opportune control algorithms for the quickly to change of working regime from ... Keywords: electric drive with induction motor, electric drive with voltage sourced inverter, voltage drop

P. Beneš; J. Fo?t; M. Pittermann

2011-09-01T23:59:59.000Z

391

A Sensitivity Study of a Theoretical Model Of SO2 Scavenging by Water Drops in Air  

Science Conference Proceedings (OSTI)

The rate at which SO2 is removed from air by a water drop has been investigated by solving numerically the convective diffusion equation for SO2 diffusing through air into a water drop where the species SO2·H2O, HSO3?, SO3? and SO4? were assumed ...

L. B. Baboolal; H. R. Pruppacher; J. H. Topalian

1981-04-01T23:59:59.000Z

392

Thermionic energy conversion research analysis. Annual progress report. [Study on plasma arc-drop  

DOE Green Energy (OSTI)

This progress report summarizes the major results presented in ''Preliminary Report on Plasma Arc-Drop in Thermionic Energy Converters,'' (COO-2533-1), and includes additional discussions on the magnitude of the normalized plasma resistance required to achieve low arc-drop converter operation.

Lam, S.H.

1976-01-01T23:59:59.000Z

393

U-199: Drupal Drag & Drop Gallery Module Arbitrary File Upload  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

9: Drupal Drag & Drop Gallery Module Arbitrary File Upload 9: Drupal Drag & Drop Gallery Module Arbitrary File Upload Vulnerability U-199: Drupal Drag & Drop Gallery Module Arbitrary File Upload Vulnerability June 26, 2012 - 7:00am Addthis PROBLEM: A vulnerability has been reported in the Drag & Drop Gallery module for Drupal, which can be exploited by malicious people to compromise a vulnerable system. PLATFORM: Drupal Drag & Drop Gallery Module 6.x ABSTRACT: The vulnerability is caused due to the sites/all/modules/dragdrop_gallery/upload.php script improperly validating uploaded files, which can be exploited to execute arbitrary PHP code by uploading a PHP file with e.g. an appended ".gif" file extension. Reference Links: Original Advisory Secunia ID 49698 No Current CVE Reference IMPACT ASSESSMENT:

394

High temperature size selective membranes  

DOE Green Energy (OSTI)

The objective of this research is to develop a high temperature size selective membrane capable of separating gas mixture components from each other based on molecular size, using a molecular sieving mechanism. The authors are evaluating two concepts: a composite of a carbon molecular sieve (CMS) with a tightly defined pore size distribution between 3 and 4 {angstrom}, and a microporous supporting matrix which provides mechanical strength and resistance to thermal degradation, and a sandwich of a CMS film between the porous supports. The high temperature membranes the authors are developing can be used to replace the current low-temperature unit operations for separating gaseous mixtures, especially hydrogen, from the products of the water gas shift reaction at high temperatures. Membranes that have a high selectivity and have both thermal and chemical stability would improve substantially the economics of the coal gasification process. These membranes can also improve other industrial processes such as the ammonia production and oil reform processes where hydrogen separation is crucial. Results of tests on a supported membrane and an unsupported carbon film are presented.

Yates, S.F.; Zhou, S.J.; Anderson, D.J.; Til, A.E. van

1994-10-01T23:59:59.000Z

395

Strategy Guideline: HVAC Equipment Sizing  

SciTech Connect

The heating, ventilation, and air conditioning (HVAC) system is arguably the most complex system installed in a house and is a substantial component of the total house energy use. A right-sized HVAC system will provide the desired occupant comfort and will run efficiently. This Strategy Guideline discusses the information needed to initially select the equipment for a properly designed HVAC system. Right-sizing of an HVAC system involves the selection of equipment and the design of the air distribution system to meet the accurate predicted heating and cooling loads of the house. Right-sizing the HVAC system begins with an accurate understanding of the heating and cooling loads on a space; however, a full HVAC design involves more than just the load estimate calculation - the load calculation is the first step of the iterative HVAC design procedure. This guide describes the equipment selection of a split system air conditioner and furnace for an example house in Chicago, IL as well as a heat pump system for an example house in Orlando, Florida. The required heating and cooling load information for the two example houses was developed in the Department of Energy Building America Strategy Guideline: Accurate Heating and Cooling Load Calculations.

Burdick, A.

2012-02-01T23:59:59.000Z

396

Land animal sizes  

NLE Websites -- All DOE Office Websites (Extended Search)

Land animal sizes Name: tamar c Status: NA Age: NA Location: NA Country: NA Date: Around 1993 Question: Why are today's land mammals so much smaller than prehistoric mammals?...

397

ARM - Measurement - Hydrometeor size  

NLE Websites -- All DOE Office Websites (Extended Search)

size size ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Hydrometeor size The size of a hydrometeor, measured directly or derived from other measurements . Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments DISDROMETER : Impact Disdrometer LDIS : Laser Disdrometer External Instruments CPOL : C-Band Polarimetric Radar Field Campaign Instruments EC-CONVAIR580-BULK : Environment Canada Convair 580 Bulk Parameters

398

Stick-Slip Sliding of Water Drops on Chemically Heterogeneous Surfaces  

E-Print Network (OSTI)

We present a comprehensive study of water drops sliding down chemically heterogeneous surfaces formed by a periodic pattern of alternating hydrophobic and hydrophilic stripes. Drops are found to undergo a stick-slip motion whose average speed is an order of magnitude smaller than that measured on a homogeneous surface having the same static contact angle. This motion is the result of the periodic deformations of the drop interface when crossing the stripes. Numerical simulations confirm this view and are used to elucidate the principles underlying the experimental observations.

Silvia Varagnolo; Davide Ferraro; Paolo Fantinel; Matteo Pierno; Giampaolo Mistura; Giorgio Amati; Luca Biferale; Mauro Sbragaglia

2013-05-06T23:59:59.000Z

399

Proposed observations of gravity waves from the early Universe via "Millikan oil drops"  

E-Print Network (OSTI)

Pairs of Planck-mass drops of superfluid helium coated by electrons (i.e., ``Millikan oil drops''), when levitated in a superconducting magnetic trap, can be efficient quantum transducers between electromagnetic (EM) and gravitational (GR) radiation. This leads to the possibility of a Hertz-like experiment, in which EM waves are converted at the source into GR waves, and then back-converted at the receiver from GR waves back into EM waves. Detection of the gravity-wave analog of the cosmic microwave background using these drops can discriminate between various theories of the early Universe.

R. Y. Chiao

2006-06-28T23:59:59.000Z

400

Proposed observations of gravity waves from the early Universe via "Millikan oil drops"  

E-Print Network (OSTI)

Pairs of Planck-mass drops of superfluid helium coated by electrons (i.e., ``Millikan oil drops''), when levitated in a superconducting magnetic trap, can be efficient quantum transducers between electromagnetic (EM) and gravitational (GR) radiation. This leads to the possibility of a Hertz-like experiment, in which EM waves are converted at the source into GR waves, and then back-converted at the receiver from GR waves back into EM waves. Detection of the gravity-wave analog of the cosmic microwave background using these drops can discriminate between various theories of the early Universe.

Chiao, R Y

2006-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Tests of Four PT-415 Coolers Installed in the Drop-in Mode  

DOE Green Energy (OSTI)

The superconducting magnets and absorbers for MICE will be cooled using PT415 pulse tube coolers. The cooler 2nd stage will be connected to magnets and the absorbers through a helium or hydrogen re-condensing system. It was proposed that the coolers be connected to the magnets in such a way that the cooler can be easily installed and removed, which permits the magnets to be shipped without the coolers. The drop-in mode requires that the cooler 1st stage be well connected to the magnet shields and leads through a low temperature drop demountable connection. The results of the PT415 drop-in cooler tests are presented.

Green, Michael A.; Wang, S.T.

2008-07-08T23:59:59.000Z

402

Distributed Sensor Coordination for Advanced Energy Systems  

NLE Websites -- All DOE Office Websites (Extended Search)

Distributed Sensor Coordination for Advanced Energy Systems Background As advanced energy systems grow in size, they require an increasing number of pressure, temperature, and...

403

Truman's decision to drop the bomb to be discussed at 70th anniversary  

NLE Websites -- All DOE Office Websites (Extended Search)

70th anniversary lecture July 10 about Truman, bomb 70th anniversary lecture July 10 about Truman, bomb Truman's decision to drop the bomb to be discussed at 70th anniversary lecture July 10 Noel Pugach will discuss Truman's decision to drop atomic bombs on Japanese cities and explain how and why he made it July 3, 2013 70th anniversary lecture July 10 about Truman, bomb Noel Pugach will discuss Truman's decision to drop atomic bombs on Japanese cities and explain how and why he made it Contact Nick Njegomir Communications Office (505) 667-5679 Email "Harry S. Truman considered the use of the atomic bomb on Japan among the most important and consequential actions of his presidency. Historians and journalists have concurred in that judgment, though some have condemned it," Pugach said. Truman's decision to drop the bomb to be discussed at 70th anniversary

404

B61-12 Life Extension Program Radar Drop Tests Completed Successfully |  

NLE Websites -- All DOE Office Websites (Extended Search)

B61-12 Life Extension Program Radar Drop Tests Completed Successfully | B61-12 Life Extension Program Radar Drop Tests Completed Successfully | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog Home > Media Room > Press Releases > B61-12 Life Extension Program Radar Drop Tests ... Press Release B61-12 Life Extension Program Radar Drop Tests Completed Successfully

405

Radiative Impacts on the Growth of Drops within Simulated Marine Stratocumulus. Part I: Maximum Solar Heating  

Science Conference Proceedings (OSTI)

The effects of solar heating and infrared cooling on the vapor depositional growth of cloud drops, and hence the potential for collection enhancement, is investigated. Large eddy simulation (LES) of marine stratocumulus is used to generate 600 ...

Christopher M. Hartman; Jerry Y. Harrington

2005-07-01T23:59:59.000Z

406

Expanded Eligibility, Drop-in Care, and Improved Nutrition Program at Child  

NLE Websites -- All DOE Office Websites (Extended Search)

Expanded Eligibility, Drop-in Care, and Expanded Eligibility, Drop-in Care, and Improved Nutrition Program at Child Development Center The Lab's Child Development Center (CDC) provides Brookhaven Science Associates (BSA) employees a top-rated and convenient onsite childcare option. Now the CDC is announcing three new program changes and improvements for BSA families. 1. Expanded Eligibility: The CDC is opening its doors to the nieces, nephews, and grandchildren of BSA employees. Spots are available for most age groups. Contact the CDC at Ext. 7416 or email brookhaven@brighthorizons.com to arrange a tour. 2. Drop-in Care: A totally new program at the CDC. The drop-in care program allows families to access high-quality childcare on an as-needed basis for

407

Characteristics of Radar-Identified Big Drop Zones in Swiss Hailstorms  

Science Conference Proceedings (OSTI)

The characteristics of the so-called “radar-identified big drop zones” (rBDZ) have been investigated. The study employs radar observations of several thunderstorms and simultaneous microphysical and vertical wind measurements with a penetrating T-...

Albert Waldvogel; Laszlo Klein; Dennis J. Musil; Paul L. Smith

1987-08-01T23:59:59.000Z

408

Heat transfer and pressure drop for air flow through enhanced passages. Final report  

SciTech Connect

An extensive experimental investigation was carried out to determine the pressure drop and heat transfer characteristics for laminar, transitional and turbulent flow of air through a smooth passage and twenty-three enhanced passages. The internal surfaces of all enhanced passages had spirally shaped geometries; these included fluted, finned/ribbed and indented surfaces. The Reynolds number (Re) was varied between 400 and 50000. The effect of heat transfer (wall cooling or fluid heating) on pressure drop is most significant within the transition region; the recorded pressure drop with heat transfer is much higher than that without heat transfer. The magnitude of this effect depends markedly on the average surface temperature and, to a lesser extent, on the geometric characteristics of the enhanced surfaces. When the pressure drop data are reduced as values of the Fanning friction factor(f), the results are about the same with and without heat transfer for turbulent flow, with moderate differences in the laminar and transition regions.

Obot, N.T.; Esen, E.B.

1992-06-01T23:59:59.000Z

409

Heat transfer and pressure drop for air flow through enhanced passages  

SciTech Connect

An extensive experimental investigation was carried out to determine the pressure drop and heat transfer characteristics for laminar, transitional and turbulent flow of air through a smooth passage and twenty-three enhanced passages. The internal surfaces of all enhanced passages had spirally shaped geometries; these included fluted, finned/ribbed and indented surfaces. The Reynolds number (Re) was varied between 400 and 50000. The effect of heat transfer (wall cooling or fluid heating) on pressure drop is most significant within the transition region; the recorded pressure drop with heat transfer is much higher than that without heat transfer. The magnitude of this effect depends markedly on the average surface temperature and, to a lesser extent, on the geometric characteristics of the enhanced surfaces. When the pressure drop data are reduced as values of the Fanning friction factor(f), the results are about the same with and without heat transfer for turbulent flow, with moderate differences in the laminar and transition regions.

Obot, N.T.; Esen, E.B.

1992-06-01T23:59:59.000Z

410

An Example of Supercooled Drizzle Drops Formed through a Collision-Coalescence Process  

Science Conference Proceedings (OSTI)

The microphysics associated with observations of supercooled drizzle drops, which formed through a condensation and collision-coalescence process, are reported and discussed. The growth environment was an 1100-m-thick stratiform cloud with cloud-...

Stewart G. Cober; J. Walter Strapp; George A. Isaac

1996-12-01T23:59:59.000Z

411

The influence of return bends on the downstream pressure drop and condensation heat transfer in tubes  

E-Print Network (OSTI)

The influence of return bends on the downstream pressure drop and heat transfer coefficient of condensing refrigerant R-12 was studied experimentally. Flow patterns in glass return bends of 1/2 to 1 in. radius and 0.315 ...

Traviss, Donald P.

1971-01-01T23:59:59.000Z

412

Characterization of Aircraft Icing Environments with Supercooled Large Drops for Application to Commercial Aircraft Certification  

Science Conference Proceedings (OSTI)

Observations of aircraft icing environments that included supercooled large drops (SLD) greater than 100 ?m in diameter have been analyzed. The observations were collected by instrumented research aircraft from 134 flights during six field ...

Stewart G. Cober; George A. Isaac

2012-02-01T23:59:59.000Z

413

Drop Formation and Breakup of Low Viscosity Elastic Fluids: Effects of Molecular Weight and Concentration  

E-Print Network (OSTI)

The dynamics of drop formation and pinch-off have been investigated for a series of low viscosity elastic fluids possessing similar shear viscosities, but differing substantially in elastic properties. On initial approach ...

Tirtaatmadja, Viyada

2007-01-23T23:59:59.000Z

414

Heat transfer to impacting drops and post critical heat flux dispersed flow  

E-Print Network (OSTI)

Heat transfer to drops impacting on a hot surface is examined in context of dispersions of flowing, boiling fluids. The liquid contribution to heat transfer from a hot tube to a two-phase dispersion is formulated in terms ...

Kendall, Gail E.

1978-01-01T23:59:59.000Z

415

A Simple Perturbation Model for the Electrostatic Shape of Falling Drops  

Science Conference Proceedings (OSTI)

A perturbation model for the shape of falling drops in the presence of electric fields and charges was developed by extension of previous methods that includes aerodynamic effects in the pressure balance equation of Laplace. Use of a consistent ...

Kenneth V. Beard; James Q. Feng; Catherine Chuang

1989-08-01T23:59:59.000Z

416

Another Look at the Influence of Absorbing Aerosols in Drops on Cloud Absorption: Large Aerosols  

Science Conference Proceedings (OSTI)

Since as early as 1969, solar absorbing aerosols inside of cloud drops have been suggested to influence cloud radiative properties. The absorbing aerosols were invoked to help explain two “anomalies”: 1) the maximum visible albedo of thick ...

Carynelisa Erlick; Dana Schlesinger

2008-02-01T23:59:59.000Z

417

Kinetics of Cloud Drop Formation and Its Parameterization for Cloud and Climate Models  

Science Conference Proceedings (OSTI)

To study the kinetics of drop nucleation in clouds, the integro–differential equation for integral water supersaturation in cloud is derived and analyzed. Solving the supersaturation equation with an algebraic form of the cloud condensation ...

Vitaly I. Khvorostyanov; Judith A. Curry

2008-09-01T23:59:59.000Z

418

Size-dependent piezoelectricity  

E-Print Network (OSTI)

In this paper, a consistent theory is developed for size-dependent piezoelectricity in dielectric solids. This theory shows that electric polarization can be generated as the result of coupling to the mean curvature tensor, unlike previous flexoelectric theories that postulate such couplings with other forms of curvature and more general strain gradient terms ignoring the possible couple- stresses. The present formulation represents an extension of recent work that establishes a consistent size-dependent theory for solid mechanics. Here by including scale-dependent measures in the energy equation, the general expressions for force- and couple-stresses, as well as electric displacement, are obtained. Next, the constitutive relations, displacement formulations, the uniqueness theorem and the reciprocal theorem for the corresponding linear small deformation size-dependent piezoelectricity are developed. As with existing flexoelectric formulations, one finds that the piezoelectric effect can also exist in isotrop...

Hadjesfandiari, Ali R

2013-01-01T23:59:59.000Z

419

Sizing and burn time measurements of micron-sized metal powders  

SciTech Connect

Detailed ignition and combustion mechanisms are needed to develop optimized propellant and energetic formulations using micron-sized metal powders, such as aluminum. Combustion researchers have traditionally used relatively coarse metal particles to characterize the burn time dependence on particle size. However, measurements of burn times for particles below 10 {mu}m in diameter are still needed for aluminum powders and other metal fuels. The apparatus described here sizes the particles just before the ignition event, providing a direct correlation between individual particle size and its burn time. Two lasers were utilized: a 785 nm laser diode for sizing the particles and a 125 W CO{sub 2} laser for particle ignition. The particles crossed the 785 nm laser beam just before crossing the CO{sub 2} laser beam. The particle size was determined from the amplitude of the scattered 785 nm light pulse. The burn time was determined from the duration of the visible light emission produced from the ignited particle. The in situ measured particle size distributions compared well with the size distributions measured for the same powders by a commercial instrument using low angle laser light scattering. Our measurements with two nominally spherical aluminum powders, suggest that the burn times increase from 0.5 to {approx}2.5 ms as the particle diameters increase from 3 to 8 {mu}m.

Gill, Robert J.; Mohan, Salil; Dreizin, Edward L. [New Jersey Institute of Technology Newark, New Jersey 07102 (United States)

2009-06-15T23:59:59.000Z

420

Particle Size Analysis of Multimodal Gamma-Prime (?') Distributions ...  

Science Conference Proceedings (OSTI)

Evolution of Internal Strain with Temperature in Depleted Uranium in the Presence of Hydrides · EXAFS Study of Local Atomic Environment in Annealed and ...

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Certification of SRM 114q: Part II (Particle size distribution)  

Science Conference Proceedings (OSTI)

... LA: Ronald J. Rajki California Portland Cement ... Mitsubishi Cement Corp., Lucerne Valley, CA: Tom ... of diffracted light around the central beam can ...

2006-12-07T23:59:59.000Z

422

The geographic distribution of mammal body size in Europe  

E-Print Network (OSTI)

palaeo/ice_topo. 2 Heat conservation — grid cell averages ofgrid cell from data available at: http:// www.ngdc.noaa.gov/seg/cdroms/ged_iia/datasets/a13/fnoc.htm. 3 Heat

Rodriguez, M A; Lopez-Sanudo, I L; Hawkins, Bradford A.

2006-01-01T23:59:59.000Z

423

Comments on "Modelling the gap size distribution of parked cars"  

E-Print Network (OSTI)

In this Comment we discuss some points concerning the modeling of parked cars proposed in the article by Rawal and Rodgers, Physica A (2005). We also introduce another approach to this problem which leads to a better description of the empirical data collected by the authors.

Girardi, Mauricio

2009-01-01T23:59:59.000Z

424

Size Distribution, Imaging and Growth Mechanisms of Self ...  

Science Conference Proceedings (OSTI)

The growth of self-assembled quantum-confined structures has been under ... being developed to better understand the formation of quantum dots and wires.

425

The Echo Size Distribution of Precipitating Shallow Cumuli  

Science Conference Proceedings (OSTI)

S-band radar surveillance scans of precipitating shallow convection are analyzed. The scans are complied from 52 days of near-continuous measurements in the winter trades of the North Atlantic during the Rain in Cumulus over the Ocean (RICO) ...

Panu Trivej; Bjorn Stevens

2010-03-01T23:59:59.000Z

426

Performance Profiles Table Browser: T-10. Size Distribution of Net ...  

U.S. Energy Information Administration (EIA)

Crude oil, gasoline, heating oil, diesel, propane, and other liquids including biofuels and natural gas liquids. Natural Gas. Exploration and reserves, storage, ...

427

Theory of Nanocluster Size Distributions from Ion Beam Synthesis  

E-Print Network (OSTI)

the implanted species/matrix interface energy. PACS numbers:on the interface energy between the matrix and the implantedenergy between the implanted species and the matrix. The

Yuan, C.W.

2009-01-01T23:59:59.000Z

428

Dispersion of Cloud Droplet Size Distributions, Cloud Parameterization...  

NLE Websites -- All DOE Office Websites (Extended Search)

National Laboratory Upton, New York Introduction Most studies of the effect of aerosols on cloud radiative properties have considered only changes in the cloud droplet...

429

Certification of SRM 114q: Part II (Particle size distribution)  

Science Conference Proceedings (OSTI)

... Physical and Chemical Properties2 • Analytical Chemistry ... and Conformance Testing • Statistical Engineering ... and the requirements for sample ...

2011-08-04T23:59:59.000Z

430

TN-68 Spent Fuel Transport Cask Analytical Evaluation for Drop Events  

SciTech Connect

The U.S. Nuclear Regulatory Commission (NRC) is responsible for licensing commercial spent nuclear fuel transported in casks certified by NRC under the Code of Federal Regulations (10 CFR), Title 10, Part 71 [1]. Both the International Atomic Energy Agency regulations for transporting radioactive materials [2, paragraph 727], and 10 CFR 71.73 require casks to be evaluated for hypothetical accident conditions, which includes a 9-meter (m) (30-ft) drop-impact event onto a flat, essentially unyielding, horizontal surface, in the most damaging orientation. This paper examines the behavior of one of the NRC certified transportation casks, the TN-68 [3], for drop-impact events. The specific area examined is the behavior of the bolted connections in the cask body and the closure lid, which are significantly loaded during the hypothetical drop-impact event. Analytical work to evaluate the NRC-certified TN-68 spent fuel transport cask [3] for a 9-m (30-ft) drop-impact event on a flat, unyielding, horizontal surface, was performed using the ANSYS® [4] and LS DYNA™ [5] finite-element analysis codes. The models were sufficiently detailed, in the areas of bolt closure interfaces and containment boundaries, to evaluate the structural integrity of the bolted connections under 9-m (30-ft) free-drop hypothetical accident conditions, as specified in 10 CFR 71.73. Evaluation of the cask for puncture, caused by a free drop through a distance of 1-m (40-in.) onto a mild steel bar mounted on a flat, essentially unyielding, horizontal surface, required by 10 CFR 71.73, was not included in the current work, and will have to be addressed in the future. Based on the analyses performed to date, it is concluded that, even though brief separation of the flange and the lid surfaces may occur under some conditions, the seals would close at the end of the drop events, because the materials remain elastic during the duration of the event.

Shah, M. J.; Klymyshyn, Nicholas A.; Adkins, Harold E.; Koeppel, Brian J.

2007-03-30T23:59:59.000Z

431

Effect of bed pressure drop on performance of a CFB boiler  

Science Conference Proceedings (OSTI)

The effect of bed pressure drop and bed inventory on the performances of a circulating fluidized bed (CFB) boiler was studied. By using the state specification design theory, the fluidization state of the gas-solids flow in the furnace of conventional CFB boilers was reconstructed to operate at a much lower bed pressure drop by reducing bed inventory and control bed quality. Through theoretical analysis, it was suggested that there would exist a theoretical optimal value of bed pressure drop, around which the boiler operation can achieve the maximal combustion efficiency and with significant reduction of the wear of the heating surface and fan energy consumption. The analysis was validated by field tests carried out in a 75 t/h CFB boiler. At full boiler load, when bed pressure drop was reduced from 7.3 to 3.2 kPa, the height of the dense zone in the lower furnace decreased, but the solid suspension density profile in the upper furnace and solid flow rate were barely influenced. Consequently, the average heat transfer coefficient in the furnace was kept nearly the same and the furnace temperature increment was less than 17{sup o}C. It was also found that the carbon content in the fly ash decreased first with decreasing bed pressure drop and then increased with further increasing bed pressure drop. The turning point with minimal carbon content was referred to as the point with optimal bed pressure drop. For this boiler, at the optimum point the bed pressure was around 5.7 kPa with the overall excess air ratio of 1.06. When the boiler was operated around this optimal point, not only the combustion efficiency was improved, but also fan energy consumption and wear of heating surface were reduced. 23 refs., 6 figs., 4 tabs.

Hairui Yang; Hai Zhang; Shi Yang; Guangxi Yue; Jun Su; Zhiping Fu [Tsinghua University, Beijing (China). Department of Thermal Engineering

2009-05-15T23:59:59.000Z

432

Genetic algorithm for optimal capacitor allocation in radial distribution systems  

Science Conference Proceedings (OSTI)

Optimum location and size of capacitors for a radial distribution system is presented. In the present study capacitor sizes are assumed as discrete known variables, which are to be placed on the buses such that it reduces the losses of the distribution ... Keywords: capacitor placement, distribution automation (DA), genetic algorithm (GA), loss minimisation, optimisation, power distribution system

K. S. Swarup

2005-06-01T23:59:59.000Z

433

Equitable distribution  

Science Conference Proceedings (OSTI)

The problem of distributing available resources occurs in a great variety of networks, each with peculiarities of its own. Coal from mines has to be distributed to central dumps and to small yards. Ice cream must be distributed only to refrigerated stores ...

John A. Gosden

1963-05-01T23:59:59.000Z

434

Ductless Hydronic Distribution  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

DUCTLESS HYDRONIC DUCTLESS HYDRONIC DISTRIBUTION Alliance for Residential Building Innovation David Springer, Davis Energy Group Context  Target: Builders of high performance new homes & deep retrofits  Why is this technology key to meeting performance goals of future homes?  Distribution Efficiency * Distribution efficiency for well insulated, tight ducts in attics ≈ 85% * Duct energy losses drives placement of ducts inside conditioned space, which adds cost and interferes with structure and architecture * Ductless hydronic systems can approach 100% distribution efficiency; piping needs little space  Delivery Energy * Fans: 0.58 W/cfm or 9 (heating) to 27 (cooling) W/kBtuh * Pumps: 8 W/gpm, or 0.8 W/kBtuh Context  Sizing * Conventional systems tend to be too large for low load homes

435

Climate Sensitivity to Continental Ice Sheet Size and Configuration  

Science Conference Proceedings (OSTI)

A version of the NCAR Community Climate Model (CCM) has been used to carry out a study of climate sensitivity to the size and distribution of continental ice sheets by comparing two perpetual season, fixed sea surface temperature (SST), winter ...

Richard A. Shinn; Eric J. Barron

1989-12-01T23:59:59.000Z

436

Microphysics of Raindrop Size Spectra: Tropical Continental and Maritime Storms  

Science Conference Proceedings (OSTI)

This work uses raindrop size spectra measured at the surface in tropical continental storms to determine the associated parameters of the best-fit gamma distributions. The physical processes responsible for those parameters and their relations to ...

Carlton W. Ulbrich; David Atlas

2007-11-01T23:59:59.000Z

437

Size separation in vibrated granular matter  

E-Print Network (OSTI)

We review recent developments in size separation in vibrated granular materials. Motivated by a need in industry to efficiently handle granular materials and a desire to make fundamental advances in non-equilibrium physics, experimental and theoretical investigations have shown size separation to be a complex phenomena. Large particles in a vibrated granular system invariably rise to the top. However, they may also sink to the bottom, or show other patterns depending on subtle variations in physical conditions. While size ratio is a dominant factor, particle specific properties such as density, inelasticity and friction can play an important role. The nature of the energy input, boundary conditions and interstitial air have been also shown to be significant factors in determining spatial distributions. The presence of convection can enhance mixing or lead to size separation. Experimental techniques including direct visualization and magnetic resonance imaging are being used to investigate these properties. Molecular dynamics and Monte Carlo simulation techniques have been developed to probe size separation. Analytical methods such as kinetic theory are being used to study the interplay between particle size and density in the vibro-fluidized regime, and geometric models have been proposed to describe size separation for deep beds. Besides discussing these studies, we will also review the impact of inelastic collision and friction on the density and velocity distributions to gain a deeper appreciation of the non-equilibrium nature of the system. While a substantial number of studies have been accomplished, considerable work is still required to achieve a firm description of the phenomena.

A. Kudrolli

2004-02-06T23:59:59.000Z

438

Experimental investigation of ice slurry flow pressure drop in horizontal tubes  

SciTech Connect

Pressure drop behaviour of ice slurry based on ethanol-water mixture in circular horizontal tubes has been experimentally investigated. The secondary fluid was prepared by mixing ethyl alcohol and water to obtain initial alcohol concentration of 10.3% (initial freezing temperature -4.4 C). The pressure drop tests were conducted to cover laminar and slightly turbulent flow with ice mass fraction varying from 0% to 30% depending on test conditions. Results from flow tests reveal much higher pressure drop for higher ice concentrations and higher velocities in comparison to the single phase flow. However for ice concentrations of 15% and higher, certain velocity exists at which ice slurry pressure drop is same or even lower than for single phase flow. It seems that higher ice concentration delay flow pattern transition moment (from laminar to turbulent) toward higher velocities. In addition experimental results for pressure drop were compared to the analytical results, based on Poiseulle and Buckingham-Reiner models for laminar flow, Blasius, Darby and Melson, Dodge and Metzner, Steffe and Tomita for turbulent region and general correlation of Kitanovski which is valid for both flow regimes. For laminar flow and low buoyancy numbers Buckingham-Reiner method gives good agreement with experimental results while for turbulent flow best fit is provided with Dodge-Metzner and Tomita methods. Furthermore, for transport purposes it has been shown that ice mass fraction of 20% offers best ratio of ice slurry transport capability and required pumping power. (author)

Grozdek, Marino; Khodabandeh, Rahmatollah; Lundqvist, Per [Royal Institute of Technology, Department of Energy Technology, Division of Applied Thermodynamics and Refrigeration, Brinellvaegen 68, 10044 Stockholm (Sweden)

2009-01-15T23:59:59.000Z

439

Drop Test Results for the Combustion Engineering Model No. ABB-2901 Fuel Pellet Package  

SciTech Connect

The U.S. Nuclear Regulatory Commission (USNRC) contracted with the Packaging Review Group (PRG) at Lawrence Livermore National Laboratory (LLNL) to conduct a single, 30-ft shallow-angle drop test on the Combustion Engineering ABB-2901 drum-type shipping package. The purpose of the test was to determine if bolted-ring drum closures could fail during shallow-angle drops. The PRG at LLNL planned the test, and Defense Technologies Engineering Division (DTED) personnel from LLNL's Site-300 Test Group executed the plan. The test was conducted in November 2001 using the drop-tower facility at LLNL's Site 300. Two representatives from Westinghouse Electric Company in Columbia, South Carolina (WEC-SC); two USNRC staff members; and three PRG members from LLNL witnessed the preliminary test runs and the final test. The single test clearly demonstrated the vulnerability of the bolted-ring drum closure to shallow-angle drops-the test package's drum closure was easily and totally separated from the drum package. The results of the preliminary test runs and the 30-ft shallow-angle drop test offer valuable qualitative understandings of the shallow-angle impact.

Hafner, R S; Mok, G C; Hagler, L G

2004-04-23T23:59:59.000Z

440

Distribution Screening for Distributed Generation  

Science Conference Proceedings (OSTI)

As the deployment of renewable distributed generation increases, the need for traditional energy providers to interact with these resources increases. Detailed modeling and simulation of the distribution and distributed resources is a critical element to better analyze, understand and predict these interactions. EPRI has developed a tool for such analysis called OpenDSS. In addition, as part of the renewable integration program an applet was created for screening distributed generation (DG). This report ...

2009-12-23T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Probing the size and environment induced phase transformation in CdSe quantum dots  

SciTech Connect

The structural and electronic properties of CdSe quantum dots in toluene and drop-casted on Si wafer were investigated by in-situ micro X-ray diffraction, X-ray photoelectron spectroscopy and UV-Vis absorption and emission spectroscopy. The in-situ micro diffraction data show that the CdSe quantum dots capped with TOPO or hexadecylamine (HDA) in toluene exhibit predominantly wurtzite crystal structure, which undergoes a phase transformation to zinc blende crystal structure following drop casting on Si and this phase transition increases with decreasing the size of the CdSe quantum dots. Decreasing the size of quantum dots also increases the Se vacancies that facilitate the phase transformation. The X-ray photoelectron spectra show a systematic increase in the core level binding energies of Cd 3d and Se 3d, the band gap and the Cd/Se ratio as the size of the quantum dots decreases from 6.6nm to 2.1nm. This is attributed to the quantum confinement of CdSe crystallites by the capping ligands in toluene which increases with decreasing the size of the quantum dots. However, drop-casting quantum dots on Si alter the density and arrangement of capping ligands and solvent molecules on the quantum dots which causes significant phase transformation.

Karakoti, Ajay S.; Sanghavi, Shail P.; Nachimuthu, Ponnusamy; Yang, Ping; Thevuthasan, Suntharampillai

2011-11-17T23:59:59.000Z

442

Generative Historical Model of City Size Hierarchies: 430 BCE –  

E-Print Network (OSTI)

Despite the enormous changes in city size and differentiation of functions over time and space, and discontinuities in growth processes, key spatio-temporal and distributional processes shaping city sizes are often assumed to remain invariant. We demonstrate in this article that most of the facile assumptions about such invariance, that is, constancy over long historical periods, are unsupported when comparisons are made concerning

Douglas R. White; Constantino Tsallis; Céline Rozenblat December

2005-01-01T23:59:59.000Z

443

Drop-in Biofuels Take Flight in Commerce City, Colorado | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Drop-in Biofuels Take Flight in Commerce City, Colorado Drop-in Biofuels Take Flight in Commerce City, Colorado Drop-in Biofuels Take Flight in Commerce City, Colorado December 8, 2011 - 12:47pm Addthis An aerial view of Rentech's Product Demonstration Unit (PDU) in Commerce City, Colorado. | Photo courtesy of Rentech. An aerial view of Rentech's Product Demonstration Unit (PDU) in Commerce City, Colorado. | Photo courtesy of Rentech. John Schueler John Schueler Former New Media Specialist, Office of Public Affairs Developing a robust, self-sustaining biofuels industry is key to our efforts to end U.S dependence on foreign oil and to ensure a secure energy future. A crucial step in advancing a domestic biofuels industry is to establish integrated biorefineries across the country. Biorefineries are similar to petroleum refineries in concept; however,

444

Better Buildings Challenge Partners Pledge 20 Percent Energy Drop By 2020 |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Better Buildings Challenge Partners Pledge 20 Percent Energy Drop Better Buildings Challenge Partners Pledge 20 Percent Energy Drop By 2020 Better Buildings Challenge Partners Pledge 20 Percent Energy Drop By 2020 November 9, 2011 - 10:00am Addthis This is the Atlanta Better Buildings Challenge Breakout Session Panel with representatives from the City of Atlanta Office of Sustainability, Southface, the U.S. General Services Administration, and two Atlanta BBC partner organizations. | Photo courtesy of Fred Perry Photography This is the Atlanta Better Buildings Challenge Breakout Session Panel with representatives from the City of Atlanta Office of Sustainability, Southface, the U.S. General Services Administration, and two Atlanta BBC partner organizations. | Photo courtesy of Fred Perry Photography Maria Tikoff Vargas

445

New directions for gravity-wave physics via "Millikan oil drops"  

E-Print Network (OSTI)

Pairs of Planck-mass--scale drops of superfluid helium coated by electrons (i.e., "Millikan oil drops"), when levitated in a superconducting magnetic trap in the presence of strong magnetic fields and at low temperatures, can be efficient quantum transducers between electromagnetic (EM) and gravitational (GR) radiation. A Hertz-like experiment, in which EM waves are converted at the source into GR waves, and then back-converted at the receiver from GR waves back into EM waves, should be practical to perform. As a step in this direction, an experiment to measure the quadrupolar electromagnetic scattering cross-section of a pair of "Millikan oil drops" will be performed first.

Chiao, R Y

2006-01-01T23:59:59.000Z

446

Drop-in Biofuels Take Flight in Commerce City, Colorado | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Drop-in Biofuels Take Flight in Commerce City, Colorado Drop-in Biofuels Take Flight in Commerce City, Colorado Drop-in Biofuels Take Flight in Commerce City, Colorado December 8, 2011 - 12:47pm Addthis An aerial view of Rentech's Product Demonstration Unit (PDU) in Commerce City, Colorado. | Photo courtesy of Rentech. An aerial view of Rentech's Product Demonstration Unit (PDU) in Commerce City, Colorado. | Photo courtesy of Rentech. John Schueler John Schueler Former New Media Specialist, Office of Public Affairs Developing a robust, self-sustaining biofuels industry is key to our efforts to end U.S dependence on foreign oil and to ensure a secure energy future. A crucial step in advancing a domestic biofuels industry is to establish integrated biorefineries across the country. Biorefineries are similar to petroleum refineries in concept; however,

447

Imbibition dynamics of nano-particulate ink-jet drops on micro-porous media  

E-Print Network (OSTI)

Imbibition dynamics of nano-particulate ink-jet drops on micro-porous media Hsiao, W.-K., Hoath, S. D., Martin, G. D., Hutchings, I. M., Chilton, N. B. and Jones, S., Proc Nanotech 2011 Conference, Boston, June 2011. Imbibition dynamics... of nano-particulate ink-jet drops on micro-porous media W.-K. Hsiao*, S. D. Hoath*, G. D. Martin*, I. M. Hutchings*, N. B. Chilton** and S. Jones** *Department of Engineering, University of Cambridge Cambridge CB3 0FS, United Kingdom, wkh26@cam...

Hsiao, W.-K.; Hoath, S.D.; Martin, G.D.; Hutchings, I.M.; Chilton, N.B.; Jones, S.

448

Influence of a local change of depth on the behavior of bouncing oil drops  

E-Print Network (OSTI)

The work of Couder \\textit{et al} (see also Bush \\textit{et al}) inspired consideration of the impact of a submerged obstacle, providing a local change of depth, on the behavior of oil drops in the bouncing regime. In the linked videos, we recreate some of their results for a drop bouncing on a uniform depth bath of the same liquid undergoing vertical oscillations just below the conditions for Faraday instability, and show a range of new behaviors associated with change of depth. This article accompanies a fluid dynamics video entered into the Gallery of Fluid Motion of the 66th Annual Meeting of the APS Division of Fluid Dynamics.

Carmigniani, Remi; Symon, Sean; McKeon, Beverley J

2013-01-01T23:59:59.000Z

449

New directions for gravity-wave physics via "Millikan oil drops"  

E-Print Network (OSTI)

Pairs of Planck-mass--scale drops of superfluid helium coated by electrons (i.e., "Millikan oil drops"), when levitated in the presence of strong magnetic fields and at low temperatures, can be efficient quantum transducers between electromagnetic (EM) and gravitational (GR) radiation. A Hertz-like experiment, in which EM waves are converted at the source into GR waves, and then back-converted at the receiver from GR waves back into EM waves, should be practical to perform. This would open up observations of the gravity-wave analog of the CMB from the extremely early Big Bang, and also communications directly through the interior of the Earth.

Raymond Y. Chiao

2006-10-29T23:59:59.000Z

450

"Millikan oil drops" as quantum transducers between electromagnetic and gravitational radiation  

E-Print Network (OSTI)

Pairs of Planck-mass-scale drops of superfluid helium coated by electrons (i.e., "Millikan oil drops"), when levitated in the presence of strong magnetic fields and at low temperatures, can be efficient quantum transducers between electromagnetic (EM) and gravitational (GR) radiation. A Hertz-like experiment, in which EM waves are converted at the source into GR waves, and then back-converted at the receiver from GR waves back into EM waves, should be practical to perform. This would open up observations of the gravity-wave analog of the Cosmic Microwave Background from the extremely early Big Bang, and also communications directly through the interior of the Earth.

Raymond Y. Chiao

2007-02-19T23:59:59.000Z

451

"Millikan oil drops" as quantum transducers between electromagnetic and gravitational radiation  

E-Print Network (OSTI)

Pairs of Planck-mass-scale drops of superfluid helium coated by electrons (i.e., "Millikan oil drops"), when levitated in the presence of strong magnetic fields and at low temperatures, can be efficient quantum transducers between electromagnetic (EM) and gravitational (GR) radiation. A Hertz-like experiment, in which EM waves are converted at the source into GR waves, and then back-converted at the receiver from GR waves back into EM waves, should be practical to perform. This would open up observations of the gravity-wave analog of the Cosmic Microwave Background from the extremely early Big Bang, and also communications directly through the interior of the Earth.

Chiao, R Y

2007-01-01T23:59:59.000Z

452

Seismic and cask drop excitation evaluation of the tower shielding reactor  

SciTech Connect

During the current shutdown of the Tower Shielding Reactor II (TSR-II), analyses were performed to determine the effect of nearby cask drops on the structural and mechanical integrity of the reactor. This evaluation was then extended to include the effects of earthquakes. Several analytic models were developed to simulate the effects of earthquake and cask drop excitation. A coupled soil-structure model was developed. As a result of the analyses, several hardware modifications and enhancements were implemented to ensure reactor integrity during future operations. 6 figs.

Harris, S.P.; Stover, R.L.; Johnson, J.J.; Sumodobila, B.N. (EQE, Inc., San Francisco, CA (USA); Oak Ridge National Lab., TN (USA); EQE, Inc., San Francisco, CA (USA))

1989-01-01T23:59:59.000Z

453

Distribution Workshop  

Energy.gov (U.S. Department of Energy (DOE))

On September 24-26, 2012, the GTT presented a workshop on grid integration on the distribution system at the Sheraton Crystal City near Washington, DC.

454

Medical, Dental & Vision Add/Drop Form Please return to: Postdoc Benefits Office, 3160 Porter Drive, Suite 250, Palo Alto, CA 94304-8443 or  

E-Print Network (OSTI)

Medical, Dental & Vision Add/Drop Form Please return to: Postdoc Benefits Office, 3160 Porter Drive Same Add Drop Medical EPO Medical PPO Dental PPO VSP Vision Postdoctoral Scholar Add Drop Medical EPO Medical PPO Dental PPO VSP Vision Spouse Domestic Partner Son Daughter Add Drop Medical EPO Medical PPO

Sonnenburg, Justin L.

455

Medical, Dental & Vision Add/Drop Form Please return to: Postdoc Benefits Office, 320 Panama Street, Bambi Modular, Stanford, CA 94305-  

E-Print Network (OSTI)

Medical, Dental & Vision Add/Drop Form Please return to: Postdoc Benefits Office, 320 Panama Street Same Add Drop Medical EPO Medical PPO Dental PPO VSP Vision Postdoctoral Scholar Add Drop Medical EPO Medical PPO Dental PPO VSP Vision Spouse Domestic Partner Son Daughter Add Drop Medical EPO Medical PPO

Kay, Mark A.

456

Usage by Job Size  

NLE Websites -- All DOE Office Websites (Extended Search)

Usage by Job Usage by Job Size Table Usage by Job Size Table page loading animation Usage Query Interface System All Hopper Edison Carver Planck Matgen Franklin Hopper 1 Magellan Dirac Bassi Jacquard Seaborg User Account (Repo) Execution Queue All Debug Interactive Premium Regular Short Regular Long Regular Small Regular Medium Regular Big Regular Extra Big Killable Low Transfer IO Task Special System Serial Big Memory Westmere === Inactive === Magellan Serial Magellan Short Magellan Small Magellan Medium Magellan Big Magellan Long Regular 1 Regular 1 Long Regular 16 Regular 32 Regular 48 Full Config Seaborg Serial Batch 16 Batch 32 Batch 64 Submit Queue all interactive debug premium regular low DOE Office all ASCR BER BES FES HEP NP Summary for jobs that completed after Jan Feb Mar Apr May Jun July Aug Sep Oct Nov Dec 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 @ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 : 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59

457

Observations of Precipitation Size and Fall Speed Characteristics within Coexisting Rain and Wet Snow  

Science Conference Proceedings (OSTI)

Ground-based measurements of particle size and fall speed distributions using a Particle Size and Velocity (PARSIVEL) disdrometer are compared among samples obtained in mixed precipitation (rain and wet snow) and rain in the Oregon Cascade ...

Sandra E. Yuter; David E. Kingsmill; Louisa B. Nance; Martin Löffler-Mang

2006-10-01T23:59:59.000Z

458

GCM Aerosol Radiative Effects Using Geographically Varying Aerosol Sizes Deduced from AERONET Measurements  

Science Conference Proceedings (OSTI)

Aerosol optical properties, and hence the direct radiative effects, are largely determined by the assumed aerosol size distribution. In order to relax the fixed aerosol size constraint commonly used in general circulation models (GCMs), ...

Glen Lesins; Ulrike Lohmann

2003-11-01T23:59:59.000Z

459

A Laboratory Method for Ash Particle Size Determination  

Science Conference Proceedings (OSTI)

Increasing stringent particulate emissions limits are putting more pressure on power producers to improve electrostatic precipitator (ESP) performance. In an effort to select the most cost effective upgrade option, many power plant engineers are using ESP computer models to estimate the impact of the available options. These models are sensitive to the fly ash particle size distribution used in the calculations, but the actual distribution is rarely known. Furthermore, measuring this distribution has, in...

2005-03-23T23:59:59.000Z

460

Contact angle hysteresis of cylindrical drops on chemically heterogeneous striped surfaces  

E-Print Network (OSTI)

Contact angle hysteresis of a macroscopic droplet on a heterogeneous but flat substrate is studied using the interface displacement model. First, the apparent contact angle of a droplet on a heterogeneous surface under the condition of constant volume is considered. By assuming a cylindrical liquid-vapor surface (meniscus) and minimizing the total free energy, we derive an equation for the apparent contact angle, which is similar but different from the well-known Cassie's law. Next, using this modified Cassie's law as a guide to predict the behavior of a droplet on a heterogeneous striped surface, we examine several scenarios of contact angle hysteresis using a periodically striped surface model. By changing the volume of the droplet, we predict a sudden jump of the droplet edge, and a continuous change of the apparent contact angle at the edge of two stripes. Our results suggest that as drop volume is increased (advancing contact lines), the predominant drop configuration observed is the one whose contact angle is large; whereas, decreasing drop volume from a large value (receding contact lines) yields drop configuration that predominantly exhibit the smaller contact angle.

Masao Iwamatsu

2005-11-26T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Radiative Impacts on the Growth of a Population of Drops within Simulated Summertime Arctic Stratus  

Science Conference Proceedings (OSTI)

The impact of solar heating and infrared cooling on the growth of a population of drops is studied with two numerical modeling frameworks. An eddy-resolving model (ERM) simulation of Arctic stratus clouds is used to generate a dataset of 500 ...

Jerry Y. Harrington; Graham Feingold; William R. Cotton

2000-03-01T23:59:59.000Z

462

FEM analysis of voltage drop in the anode connector induced by steel stub diameter reduction  

Science Conference Proceedings (OSTI)

Primary aluminium production is a high-energy consumption process, and improving the energy efficiency of smelters could be economically viable. An issue in the Hall-Heroult prebake anode technology is the voltage drop in the anode connector caused by ... Keywords: Aluminium reduction cell, Carbon anode, Energy efficiency, Finite element method, Stub hole, Thermo-electro-mechanical modelling

Hugues Fortin; Nedeltcho Kandev; Mario Fafard

2012-05-01T23:59:59.000Z

463

Determination of robot drop location for military path planning using GIS application  

Science Conference Proceedings (OSTI)

Due to the uncertainties and higher risks of fatality in combat situations, Unmanned Ground Robots (UGR) may be proven to be a safer alternative for carrying out critical military missions, such as search and rescue, and reconnaissance operations. Among ... Keywords: military path planning, robot drop, unmanned ground robot

Min-Wook Kang; Manoj K. Jha; Gautham Karri

2010-01-01T23:59:59.000Z

464

Hydroclimatic Factors of the Recent Record Drop in Laurentian Great Lakes Water Levels  

Science Conference Proceedings (OSTI)

An extreme low-water supply episode from 1997 to 2000 resulted in the largest 1-yr drop in Lakes Michigan–Huron and Lake Erie water levels (0.92 and 1.03 m, respectively) recorded since measurements began in the early 1800s. Lake Superior water ...

Raymond A. Assel; Frank H. Quinn; Cynthia E. Sellinger

2004-08-01T23:59:59.000Z

465

CFD analysis of the effect of elbow radius on pressure drop in multiphase flow  

Science Conference Proceedings (OSTI)

Computational fluid dynamics (CFD) analysis was performed in four different 90 degree elbows with air-water two-phase flows. The inside diameters of the elbows were 6.35mm and 12.7mm with radius to diameter ratios (r/D) of 1.5 to 3. The pressure drops ...

Quamrul H. Mazumder

2012-01-01T23:59:59.000Z

466

Regimes of polymer behaviour in drop-on-demand ink-jetting  

E-Print Network (OSTI)

and Ian M Hutchings, University of Cambridge, Cambridge UK; Oliver G Harlen, Claire McIlroy and Neil F Morrison, University of Leeds, Leeds UK Abstract A recent model for the drop-on-demand (DoD) jetting of mono-disperse linear polymer solutions...

Hoath, S.D.; Hutchings, I.M.; Harlen, O.G.; McIIroy, C.; Morrison, N.F.

2012-01-01T23:59:59.000Z

467

Potential drop mapping for the monitoring of corrosion or erosion Giuseppe Sposito a  

E-Print Network (OSTI)

in boilers at a power plant was succ resistance Corrosion Erosion a b s t r a c t Potential drop techniques have been employed in the power [1,2], for monitoring the growth of surface-breaking cracks [3­7] and for the characterisation

Nagy, Peter B.

468

Lattice Boltzmann simulations of micron-scale drop impact on dry surfaces  

Science Conference Proceedings (OSTI)

A lattice Boltzmann equation (LBE) method for incompressible binary fluids is proposed to model the contact line dynamics on partially wetting surfaces. Intermolecular interactions between a wall and fluids are represented by the inclusion of the cubic ... Keywords: Contact line dynamics, Drop impact, Lattice Boltzmann method, Parasitic currents

Taehun Lee; Lin Liu

2010-10-01T23:59:59.000Z

469

Fig. 1: Journal Articles Tab on library homepage Fig. 2 Drop down menu Engineering  

E-Print Network (OSTI)

-campus, you will be prompted to enter your myWSU ID and password as soon as you click the "search" button allows you to separate several search terms or phrases in various fields with the drop-down menu (figure search terms and list the databases it is searching (fig. 8). When the search is completed, the window

470

A study of pressure losses in residential air distribution systems  

Science Conference Proceedings (OSTI)

An experimental study was conducted to evaluate the pressure drop characteristics of residential duct system components that are either not available or not thoroughly (sometimes incorrectly) described in existing duct design literature. The tests were designed to imitate cases normally found in typical residential and light commercial installations. The study included three different sizes of flexible ducts, under different compression configurations, splitter boxes, supply boots, and a fresh air intake hood. The experimental tests conformed to ASHRAE Standard 120P--''Methods of Testing to Determine Flow Resistance of HVAC Air Ducts and Fittings''. The flexible duct study covered compressibility and bending effects on the total pressure drop, and the results showed that the available published references tend to underestimate the effects of compression in flexible ducts that can increase pressure drops by up to a factor of nine. The supply boots were tested under different configurations including a setup where a flexible duct elbow connection was considered as an integral part of the supply boot. The supply boots results showed that diffusers can increase the pressure drop by up to a factor of two in exit fittings, and the installation configuration can increase the pressure drop by up to a factor of five. The results showed that it is crucial for designers and contractors to be aware of the compressibility effects of the flexible duct, and the installation of supply boots and diffusers.

Abushakra, Bass; Walker, Iain S.; Sherman, Max H.

2002-07-01T23:59:59.000Z

471

HI-STAR 100 Spent Fuel Transport Cask Analytical Evaluation for Drop Events  

Science Conference Proceedings (OSTI)

The U.S. Nuclear Regulatory Commission (NRC) is responsible for licensing commercial spent nuclear fuel transported in casks certified by NRC under the Code of Federal Regulations (CFR), Title 10, Part 71 [1]. Both the International Atomic Energy Agency (IAEA) regulations for transporting radioactive materials [2, paragraph 727], and 10 CFR 71.73 require casks to be evaluated for hypothetical accident conditions, which includes a 9-meter (m) (30-ft) drop impact event on a flat, essentially unyielding, horizontal surface, in the most damaging orientation. This paper examines the behavior of one of the NRC-certified transportation casks, the HI-STAR 100 [3], for drop impact events. The specific area examined is the behavior of the bolted connections in the “overpack” top flange and the closure plate, which are significantly loaded during the hypothetical drop impact event. The term “overpack” refers to the cask that receives and contains a sealed multi-purpose canister (MPC) containing spent nuclear fuel. The analytical work to evaluate the NRC-certified HI-STAR 100 spent fuel transport cask [3] for a 9-m (30-ft) drop impact event on a flat, unyielding, horizontal surface, was performed using the ANSYS® [4] and LS DYNA™ [5] finite-element analysis codes. The models were sufficiently detailed, in the areas of bolt closure interfaces and containment boundaries, to evaluate the structural integrity of the bolted connections under 9-m (30-ft) free-drop hypothetical accident conditions, as specified in 10 CFR 71.73. Evaluation of the cask for puncture, caused by a free-drop through a distance of 1-m (40-in.) onto a mild steel bar mounted on a flat, essentially unyielding, horizontal surface, required by 10 CFR 71.73, was not included in the current work, and will have to be addressed in the future. Based on the analyses performed to date, it is concluded that, even though brief separation of the flange and the closure plate surfaces may occur, the seals would close at the end of the drop events, because the materials remain elastic during the duration of the event.

Shah, M. J.; Klymyshyn, Nicholas A.; Adkins, Harold E.; Koeppel, Brian J.

2007-03-30T23:59:59.000Z

472

Incorporating Voltage Fluctuations of the Power Distribution Network into the Transient Analysis of CMOS Logic Gates  

Science Conference Proceedings (OSTI)

Decreased power supply levels have reduced the tolerance to voltage changes within power distribution networks in CMOS integrated circuits. High on-chip currents, required to charge and discharge large on-chip loads while operating at high frequencies, ... Keywords: IR drops, power distribution network, system-on-a-chip

Kevin T. Tang; Eby G. Friedman

2002-05-01T23:59:59.000Z

473

The CO2 Abatement Potential of California's Mid-sized Commerical...  

NLE Websites -- All DOE Office Websites (Extended Search)

mid-sized commercial sites in California (CA), existing tariffs of three major electricity distribution ultilities, and performance data of available technology in 2020,...

474

Dog's Heart Size and Activity  

NLE Websites -- All DOE Office Websites (Extended Search)

Dog's Heart Size and Activity Name: Addie Status: Student Grade: 4-5 Location: IN Country: USA Date: Winter 2009-2010 Question: Does the size of a dog affect it's heart rate before...

475

Unclassified Distribution  

NLE Websites -- All DOE Office Websites (Extended Search)

63 1 Unclassified Distribution UNIVERSITY :OF CALIFORNU Radiation Lab oratory Contract No, W-7405-eng-48 THE DETECTION OF U T I F I C I B L L Y PRODUCED WOTOMESONS WITH COUNTERS *...

476

Automated size analysis for OCL  

Science Conference Proceedings (OSTI)

An essential tool in object oriented modeling is the specification of cardinalities of associations between classes. In Object Constraint Language (OCL) such constraints are expressed as conditions on the sizes of the collections that correspond to associations. ... Keywords: OCL, size abstraction, size analysis

Fang Yu; Tevfik Bultan; Erik Peterson

2007-09-01T23:59:59.000Z

477

Special Distribution  

Office of Legacy Management (LM)

Special Distribution Special Distribution Issued: December 1977 ',, Radiological Survey and Decontamination of the Former Main Technical Area (TA-1) at Los Alamos, New Mexico Compiled by A. John Ahlquist Alan K. Stoker Linda K. Trocki c laboratory of, the University of California LOS ALAMOS, NEW MEXICO 87545 An Alfirmdve Action/Equal Opportunity Employer ..-_- .-- .--.-. c T -,--... _ _._-r..l __,.. - .-,_.. ..- _._ -- .--. " . . _ . - . c- - . . . _ -. . _ . - . - . _ - - n - _ _~ ~_. __ _ ~~_ --..&e+ L.';; CONTENTS ABSTRACT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .._____ 1 EXECUTIVE SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .._... _._ 2 I. BACKGROUND .............................................. 15

478

Distribution Effectiveness and Impacts on Equipment Sizing for Residential Thermal Distribution Systems  

E-Print Network (OSTI)

was installed to supply cooling for the test cell, which was built to validate the heat balance and radiant time series cooling load calculation procedures. However, some instrumentation has been added which provides and a Brief Description of Experimental Apparatus The experimental apparatus is in a test cell building

479

Distribution effectiveness and impacts on equipment sizing for residential thermal distribution systems  

SciTech Connect

This report was prepared as a result of work sponsored by the California Energy Commission (Commission), through a contract with the Regents of the University of California, California Institute for Energy Efficiency (CIEE). It does not necessarily represent the views of the Commission, its employees, the State of California, The Regents, or CIEE. The Commission, the Regents, the State of California, CIEE, their employees, contractors, and subcontractors, make no warranty, express or implied, and assume no legal liability for the information in this report; nor does any party represent that the use of this information will not infringe upon privately owned rights. This report has not been approved or disapproved by the Commission or CIEE, nor has the Commission or CIEE passed upon the accuracy or adequacy of the information in this report.

Walker, Iain; Sherman, M.; Siegel, J.

1999-06-01T23:59:59.000Z

480

Distribution Effectiveness and Impacts on Equipment Sizing for Residential Thermal Distribution Systems  

E-Print Network (OSTI)

Proc. ASHRAE/DOE/BTECC/CIBSE Thermal Performance of theProc. ASHRAE/DOE/BTECC/CIBSE Thermal Performance of the

Walker, Iain; Sherman, M.; Siegel, J.

1999-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "drop size distribution" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Two-phase pressure drop in vertical crossflow across a horizontal tube bundle  

Science Conference Proceedings (OSTI)

An experimental investigation has been made to evaluate the friction, acceleration, and hydrostatic pressure drops in two-phase vertical crossflow across a horizontal tube bundle through the measurement of the void fraction and determination of the two-phase friction multiplier. The void fractions were found to increase with increasing mass velocity for a fixed quality level. The two-phase friction multiplier increased with increasing mass velocity for a fixed value of the Martinelli parameter in both slug and spray flow and decreased with increasing mass velocity in bubbly flows. The void fraction and two-phase friction multiplier data were correlated and used to predict with very good results the total pressure drop occurring in simulated diabatic flow tests and in actual diabatic tests using R-113.

Schrage, D.S.; Hsu, J.T.; Jensen, M.K.

1988-01-01T23:59:59.000Z

482

Subcooled and saturated water flow boiling pressure drop in small diameter helical coils at low pressure  

SciTech Connect

Experimental pressure drop results on boiling water flow through three helical coils of tube inner diameter of 4.03 mm and 4.98 mm and coil diameter to tube diameter ratio of 26.1, 64.1 and 93.3 are presented. Both subcooled and saturated flow boiling are investigated, covering operating pressures from 120 to 660 kPa, mass fluxes from 290 to 690 kg m{sup -2} s{sup -1} and heat fluxes from 50 to 440 kW m{sup -2}. Existing correlations for subcooled flow pressure drop are found not capable to fit the present subcooled database, while the measurements in saturated flow conditions are successfully reproduced by existing correlations for both straight and coiled pipe two-phase flow. The experimental database is included in tabular form. (author)

Cioncolini, Andrea; Santini, Lorenzo; Ricotti, Marco E. [Department of Nuclear Engineering, Politecnico di Milano, via Ponzio 34/3, 20133 Milano (Italy)

2008-05-15T23:59:59.000Z

483

Coefficients and terms of the liquid drop model and mass formula  

E-Print Network (OSTI)

The coefficients of different combinations of terms of the liquid drop model have been determined by a least square fitting procedure to the experimental atomic masses. The nuclear masses can also be reproduced using a Coulomb radius taking into account the increase of the ratio $R\\_0/A^{1/3}$ with increasing mass, the fitted surface energy coefficient remaining around 18 MeV.

G. Royer; C. Gautier

2006-08-28T23:59:59.000Z

484

Determination of the cathode and anode voltage drops in high power low-pressure amalgam lamps  

Science Conference Proceedings (OSTI)

For the first time, cathode and anode drops of powerful low-pressure amalgam lamps were measured. The lamp discharge current is 3.2 A, discharge current frequency is 43 kHz, linear electric power is 2.4 W/cm. The method of determination of a cathode drop is based on the change of a lamp operating voltage at variation of the electrode filament current at constant discharge current. The total (cathode plus anode) drop of voltage was measured by other, independent ways. The maximum cathode fall is 10.8 V; the anode fall corresponding to the maximal cathode fall is 2.4 V. It is shown that in powerful low pressure amalgam lamps the anode fall makes a considerable contribution (in certain cases, the basic one) to heating of electrodes. Therefore, the anode fall cannot be neglected, at design an electrode and ballast of amalgam lamps with operating discharge current frequency of tens of kHz.

Vasilyak, L. M., E-mail: vasilyak@ihed.ras.ru [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation); Vasiliev, A. I., E-mail: vasiliev@npo.lit.ru; Kostyuchenko, S. V.; Sokolov, D. V.; Startsev, A. Yu. [Joint Stock Company NPO LIT (Russian Federation); Kudryavtsev, N. N. [Moscow Institute of Physics and Technology (State University) (Russian Federation)

2011-12-15T23:59:59.000Z

485

An experimental investigation of pressure drop of aqueous foam in laminar tube flow  

DOE Green Energy (OSTI)

This report is the first of two detailing pressure-drop and heat-transfer measurements made at the Foam Flow Heat Transfer Loop. The work was motivated by a desire to extend the application of aqueous foam from petroleum drilling to geothermal drilling. Pressure-drop measurements are detailed in this report; a forthcoming report (SAND85-1922) will describe the heat-transfer measurements. The pressure change across a 2.4-m (8-ft) length of the 2.588-cm (1.019-in.) ID test section was measured for liquid volume fractions between 0.05 and 0.35 and average velocities between 0.12 and 0.80 m/s (0.4 and 2.6 ft/s). The resulting pressure-drop/flow-rate data were correlated to a theoretical model for a Bingham plastic. Simple expressions for the dynamic viscosity and the yield stress as a function of liquid volume fraction were estimated.

Blackwell, B.F.; Sobolik, K.B.

1987-04-01T23:59:59.000Z

486

Pressure drop and heat transfer characteristics of boiling water in sub-hundred micron channel  

SciTech Connect

The current work focuses on the pressure drop, heat transfer and stability in two phase flow in microchannels with hydraulic diameter of less than one hundred microns. Experiments were conducted in smooth microchannels of hydraulic diameter of 45, 65 {mu}m, and a rough microchannel of hydraulic diameter of 70 {mu}m, with deionised water as the working fluid. The local saturation pressure and temperature vary substantially over the length of the channel. In order to correctly predict the local saturation temperature and subsequently the heat transfer characteristics, numerical techniques have been used in conjunction with the conventional two phase pressure drop models. The Lockhart-Martinelli (liquid-laminar, vapour-laminar) model is found to predict the two phase pressure drop data within 20%. The instability in two phase flow is quantified; it is found that microchannels