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Note: This page contains sample records for the topic "modeling variable refrigerant" from the National Library of EnergyBeta (NLEBeta).
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We encourage you to perform a real-time search of NLEBeta
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1

A Variable Refrigerant Flow Heat Pump Computer Model in EnergyPlus  

SciTech Connect

This paper provides an overview of the variable refrigerant flow heat pump computer model included with the Department of Energy's EnergyPlusTM whole-building energy simulation software. The mathematical model for a variable refrigerant flow heat pump operating in cooling or heating mode, and a detailed model for the variable refrigerant flow direct-expansion (DX) cooling coil are described in detail.

Raustad, Richard A. [Florida Solar Energy Center

2013-01-01T23:59:59.000Z

2

Multiple-Zone Variable Refrigerant Flow System Modeling and Equipment Performance Mapping  

Science Conference Proceedings (OSTI)

We developed a variable refrigerant flow (VRF) vapor compression system model, which has five indoor units, one outdoor unit and one water heater. The VRF system can run simultaneous space conditioning (cooling or heating) and water heating. The indoor units and outdoor unit use fin-&-tube coil heat exchangers, and the water heater uses a tube-in-tube heat exchanger. The fin-&-tube coil heat exchangers are modeled using a segment-by-segment approach and the tube-in-tube water heater is modeled using a phase-by-phase approach. The compressor used is a variable-speed rotary design. We calibrated our model against a manufacturer s product literature. Based on the vapor compression system model, we investigated the methodology for generating VRF equipment performance maps, which can be used for energy simulations in TRNSYS and EnergyPlus, etc. In the study, the major independent variables for mapping are identified and the deviations between the simplified performance map and the actual equipment system simulation are quantified.

Shen, Bo [ORNL; Rice, C Keith [ORNL

2012-01-01T23:59:59.000Z

3

Compare Energy Use in Variable Refrigerant Flow Heat Pumps Field Demonstration and Computer Model  

SciTech Connect

Variable Refrigerant Flow (VRF) heat pumps are often regarded as energy efficient air-conditioning systems which offer electricity savings as well as reduction in peak electric demand while providing improved individual zone setpoint control. One of the key advantages of VRF systems is minimal duct losses which provide significant reduction in energy use and duct space. However, there is limited data available to show their actual performance in the field. Since VRF systems are increasingly gaining market share in the US, it is highly desirable to have more actual field performance data of these systems. An effort was made in this direction to monitor VRF system performance over an extended period of time in a US national lab test facility. Due to increasing demand by the energy modeling community, an empirical model to simulate VRF systems was implemented in the building simulation program EnergyPlus. This paper presents the comparison of energy consumption as measured in the national lab and as predicted by the program. For increased accuracy in the comparison, a customized weather file was created by using measured outdoor temperature and relative humidity at the test facility. Other inputs to the model included building construction, VRF system model based on lab measured performance, occupancy of the building, lighting/plug loads, and thermostat set-points etc. Infiltration model inputs were adjusted in the beginning to tune the computer model and then subsequent field measurements were compared to the simulation results. Differences between the computer model results and actual field measurements are discussed. The computer generated VRF performance closely resembled the field measurements.

Sharma, Chandan; Raustad, Richard

2013-06-01T23:59:59.000Z

4

Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems  

E-Print Network (OSTI)

Amarnath, M. Blatt, Variable refrigerant flow: where, why,simulation in the variable refrigerant flow air-conditioningsimulation of the variable refrigerant flow air conditioning

Hong, Tainzhen

2010-01-01T23:59:59.000Z

5

Technical Subtopic 2.1: Modeling Variable Refrigerant Flow Heat Pump and Heat Recovery Equipment in EnergyPlus  

Science Conference Proceedings (OSTI)

The University of Central Florida/Florida Solar Energy Center, in cooperation with the Electric Power Research Institute and several variable-refrigerant-flow heat pump (VRF HP) manufacturers, provided a detailed computer model for a VRF HP system in the United States Department of Energy's (U.S. DOE) EnergyPlus? building energy simulation tool. Detailed laboratory testing and field demonstrations were performed to measure equipment performance and compare this performance to both the manufacturer's data and that predicted by the use of this new model through computer simulation. The project goal was to investigate the complex interactions of VRF HP systems from an HVAC system perspective, and explore the operational characteristics of this HVAC system type within a laboratory and real world building environment. Detailed laboratory testing of this advanced HVAC system provided invaluable performance information which does not currently exist in the form required for proper analysis and modeling. This information will also be useful for developing and/or supporting test standards for VRF HP systems. Field testing VRF HP systems also provided performance and operational information pertaining to installation, system configuration, and operational controls. Information collected from both laboratory and field tests were then used to create and validate the VRF HP system computer model which, in turn, provides architects, engineers, and building owners the confidence necessary to accurately and reliably perform building energy simulations. This new VRF HP model is available in the current public release version of DOE?s EnergyPlus software and can be used to investigate building energy use in both new and existing building stock. The general laboratory testing did not use the AHRI Standard 1230 test procedure and instead used an approach designed to measure the field installed full-load operating performance. This projects test methodology used the air enthalpy method where relevant air-side parameters were controlled while collecting output performance data at discreet points of steady-state operation. The primary metrics include system power consumption and zonal heating and cooling capacity. Using this test method, the measured total cooling capacity was somewhat lower than reported by the manufacturer. The measured power was found to be equal to or greater than the manufacturers indicated power. Heating capacity measurements produced similar results. The air-side performance metric was total cooling and heating energy since the computer model uses those same metrics as input to the model. Although the sensible and latent components of total cooling were measured, they are not described in this report. The test methodology set the thermostat set point temperature very low for cooling and very high for heating to measure full-load performance and was originally thought to provide the maximum available capacity. Manufacturers stated that this test method would not accurately measure performance of VRF systems which is now believed to be a true statement. Near the end of the project, an alternate test method was developed to better represent VRF system performance as if field installed. This method of test is preliminarily called the Load Based Method of Test where the load is fixed and the indoor conditions and unit operation are allowed to fluctuate. This test method was only briefly attempted in a laboratory setting but does show promise for future lab testing. Since variable-speed air-conditioners and heat pumps include an on-board control algorithm to modulate capacity, these systems are difficult to test. Manufacturers do have the ability to override internal components to accommodate certification procedures, however, it is unknown if the resulting operation is replicated in the field, or if so, how often. Other studies have shown that variable-speed air-conditioners and heat pumps do out perform their single-speed counterparts though these field studies leave as many questions as they do provide answers. The measure

Raustad, Richard; Nigusse, Bereket; Domitrovic, Ron

2013-09-30T23:59:59.000Z

6

Proposed Methodology for LEED Baseline Refrigeration Modeling (Presentation)  

SciTech Connect

This PowerPoint presentation summarizes a proposed methodology for LEED baseline refrigeration modeling. The presentation discusses why refrigeration modeling is important, the inputs of energy models, resources, reference building model cases, baseline model highlights, example savings calculations and results.

Deru, M.

2011-02-01T23:59:59.000Z

7

Performance Assessment of a Variable Refrigerant Flow Heat Pump Air Conditioning System  

Science Conference Proceedings (OSTI)

Variable refrigerant flow (VRF) technology uses smart integrated controls, variable speed drives, and refrigerant piping to provide energy efficiency, flexible operation, ease of installation, low noise, zone control, and comfort through all-electric technology. This report describes and documents the construction, performance, and application of a heat pump air conditioning system that uses VRF technology8212the Daikin VRV system. This variable refrigerant volume (VRV) system is manufactured by Daikin I...

2008-12-17T23:59:59.000Z

8

Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems  

E-Print Network (OSTI)

comparison of VAV and VRF air conditioning systems in anThe variable refrigerant flow (VRF) and ground source heatthe energy efficiency of VRF systems compared with GSHP

Hong, Tainzhen

2010-01-01T23:59:59.000Z

9

Impact of the Variable Refrigerant Volume Air Conditioning System on Building Energy Efficiency  

E-Print Network (OSTI)

The application of the variable refrigerant volume multi-zone air conditioning systems has met with mixed results since the publication of the Design Standard for Energy Efficiency of Public Buildings. This paper analyzes the characteristics of the variable refrigerant volume multi-zone air conditioning system, and discusses the advantages of its application.

Zhu, H.

2006-01-01T23:59:59.000Z

10

Comparing Variable Refrigerant Flow to Traditional Heating and Cooling Technologies: Assessing VRF Performance in Mobile, Alabama  

Science Conference Proceedings (OSTI)

In America, most conditioned air is delivered by ductwork, which is often made of sheet metal covered in insulation and installed during construction. However, in Japan and Europe, because the office buildings often pre-date the invention of air conditioning, it is easier and more common for refrigerant pipes to run to wall- or ceiling-mounted heat exchangers. Using refrigerant pipes instead of ducting can eliminate duct loss and offer more precise control. Are Variable Refrigerant Flow (VRF) ...

2013-09-04T23:59:59.000Z

11

Detailed CFD modelling of open refrigerated display cabinets  

Science Conference Proceedings (OSTI)

A comprehensive and detailed computational fluid dynamics (CFDs) modelling of air flow and heat transfer in an open refrigerated display cabinet (ORDC) is performed in this study. The physical-mathematical model considers the flow through the internal ...

Pedro Dinis Gaspar; L. C. Carrilho Gonçalves; R. A. Pitarma

2012-01-01T23:59:59.000Z

12

On the Use of a Mixed Integer Nonlinear Programming Model for Refrigerant Design  

E-Print Network (OSTI)

In this paper, a novel mixed integer nonlinear programming model for single component refrigerant design is presented. At the heart of the approach is a new formulation for structural feasibility that allows multiple bonds, connectivity and isomers. The strategy defines a set of structural groups (consisting of atoms), subsets of which are combined to form refrigerant molecules. Molecules formed this way must obey structural and stability constraints. The design objective is to build a refrigerant molecule that has desired physical properties and performance characteristics. These attributes are formulated as mathematical programming constraints and performance objectives which involve both continuous and integer variables. With the current renewed interest in the environment, the suggested approach is applied to refrigerant design with an environmental constraint. The results indicate the viability and the flexibility of the approach. 1 Introduction The search for new compounds wit...

In International; Nachiket Churi; Luke E. K. Achenie; Copyright Luke; E. K. Achenie

1997-01-01T23:59:59.000Z

13

Energy Simulation of Integrated Multiple-Zone Variable Refrigerant Flow System  

Science Conference Proceedings (OSTI)

We developed a detailed steady-state system model, to simulate the performance of an integrated five-zone variable refrigerant flow (VRF)heat pump system. The system is multi-functional, capable of space cooling, space heating, combined space cooling and water heating, and dedicated water heating. Methods were developed to map the VRF performance in each mode, based on the abundant data produced by the equipment system model. The performance maps were used in TRNSYS annual energy simulations. Using TRNSYS, we have successfully setup and run cases for a multiple-split, VRF heat pump and dehumidifier combination in 5-zone houses in 5 climates that control indoor dry-bulb temperature and relative humidity. We compared the calculated energy consumptions for the VRF heat pump against that of a baseline central air source heat pump, coupled with electric water heating and the standalone dehumidifiers. In addition, we investigated multiple control scenarios for the VRF heat pump, i.e. on/off control, variable indoor air flow rate, and using different zone temperature setting schedules, etc. The energy savings for the multiple scenarios were assessed.

Shen, Bo [ORNL; Rice, C Keith [ORNL; Baxter, Van D [ORNL

2013-01-01T23:59:59.000Z

14

Variable Refrigerant Flow Air Conditioners and Heat Pumps for Commercial Buildings  

Science Conference Proceedings (OSTI)

Multi-split heat pumps have evolved from a technology suitable for residential and light commercial buildings to variable refrigerant flow (VRF) systems that can provide efficient space conditioning for large commercial buildings. VRF systems are enhanced versions of ductless multi-split systems, permitting more indoor units to be connected to each outdoor unit and providing additional features such as simultaneous heating and cooling and heat recovery. VRF systems are very popular in Asia and Europe and...

2008-01-25T23:59:59.000Z

15

Chapter 3: Refrigeration Process Control: Case Study Model 42 33.. RREEFFRRIIGGEERRAATTIIOONN PPRROOCCEESSSS  

E-Print Network (OSTI)

are needed, and the required allowances in design are made to account for this. #12;Chapter 3: RefrigerationChapter 3: Refrigeration Process Control: Case Study Model 42 33.. RREEFFRRIIGGEERRAATTIIOONN-stage refrigeration system case study. It describes in detail the mathematical model developed, highlighting

Skogestad, Sigurd

16

Chapter 4: Refrigeration Process Control: Simulation Model 64 44.. RREEFFRRIIGGEERRAATTIIOONN PPRROOCCEESSSS  

E-Print Network (OSTI)

Chapter 4: Refrigeration Process Control: Simulation Model 64 44.. RREEFFRRIIGGEERRAATTIIOONN of the simulation model for the two-stage refrigeration system is presented. The model is based on the mathematical equations and transfer functions. Typical application areas are control system design, chemical process

Skogestad, Sigurd

17

Modeling the effects of Refrigerant Charging on Air Conditioner Performance Characteristics For Three Expansion Devices  

E-Print Network (OSTI)

An experimental and analytical study concerned with the off-design refrigerant charging of air conditioners is presented. A series of experiments were conducted to characterize the effects of refrigerant charge and type of expansion device on the system performance (capacity, EER, SEER, etc.) of an air conditioner. All experiments were performed according to the ASHRAE Standard [1983]. The effects of off-design refrigerant charge in the system, type of expansion device (capillary tube, TXV, and short-tube orifice), and outdoor dry-bulb temperature (82° to l00°F) on the wet and dry steady state and cyclic tests are addressed in this study. The fully charged condition was established as a base case for all the expansion device systems. A full charge was obtained by charging the unit to the superheat or subcooled condition specified by the manufacturer charging chan. Once the full charge was determined, refrigerant was then added in 5% increments from -20% of full charge to +20% of full charge to cover the full range of charging conditions for a particular expansion device being tested. The investigation of off-design charging indicated that the system performance variables (total capacity, EER, and SEER) of the unit with capillary tube were more sensitive to off-design charging than the systems with TXV and short-tube orifice. From -20% to +20% charging, the capacity and EER showed a strong dependence on the outdoor temperature, but varied little with charge for the TXV and short-tube orifice expansion systems. A -20% charging resulted in a 21% reduction in SEER while a +20% charging produced an 11% reduction in SEER for the unit with capillary tube. For the TXV, SEER dropped 2% and 8% for -20% and +20% refrigerant charging, respectively. The SEER was constant at 9.4 for all the charging condition except for -5% charging where it peaked to 9.9 for the short-tube orifice expansion system. This trend would suggest that the range of sensitivity of a short-tube orifice system is confined within a small refrigerant charge. A new heat exchanger model based on tube-by-tube simulation was developed and integrated into the ORNL heat pump model. The model was capable of simulating the steady state response of a vapor compression air-to-air heat pump and air conditioner commonly used in residential applications. The simulated results were compared with laboratory tests at two outdoor temperatures. It was found that the ORNL model estimates were within an average of 3% of the experimental results from - 10% to +10% charging conditions. The model predicted the system performance up to 8% higher than measured results at +/-20% and +/-15% charging conditions. Among the eight void fraction models studied, the Hughmark model showed the best agreement between superheat and subcooled temperatures, refrigerant flow rate and capacity and the measured results.

Farzad, Mohsen

1990-08-01T23:59:59.000Z

18

Modeling 18° Water Variability  

Science Conference Proceedings (OSTI)

Variability of 18° Water formation is investigated with an isopycnic-coordinate model of the North Atlantic. A 30-year spinup integration is used as a “control” experiment in which the upper water column in the Sargasso Sea is shown to be in ...

Robert Marsh; Adrian L. New

1996-06-01T23:59:59.000Z

19

Variability within Modeling Language Definitions  

Science Conference Proceedings (OSTI)

We present a taxonomy of the variability mechanisms offered by modeling languages. The definition of a formal language encompasses a syntax and a semantic domain as well as the mapping that relates them, thus language variabilities are classified according ... Keywords: Modeling languages, UML, formal semantics, variability

María Victoria Cengarle; Hans Grönniger; Bernhard Rumpe

2009-10-01T23:59:59.000Z

20

Improved Algorithm and Simulation of the Provision Refrigerating Unit  

Science Conference Proceedings (OSTI)

The dynamic model of reciprocating provision cooling plant is presented, and the algorithm of the model is amended, through the method of quoting an unknown variable, which is enthalpy of the refrigerant at the compressor outlet. Dynamic simulation of ...

HE Zhi-bin; ZHANG Jun-dong; SUN Yu-qing; ZENG Hong; GAN Hui-bing

2007-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems  

E-Print Network (OSTI)

Comparison of energy efficiency between variable refrigeranttheir superior energy efficiency. The variable refrigerantfew studies reporting the energy efficiency of VRF systems

Hong, Tainzhen

2010-01-01T23:59:59.000Z

22

Design of a single orifice pulse tube refrigerator through the development of a first-order model  

E-Print Network (OSTI)

A first order model for the behavior of a linear orifice pulse tube refrigerator (OPTR) was developed as a design tool for construction of actual OPTRs. The model predicts cooling power as well as the pressure/volume ...

Schor, Alisha R. (Alisha Robin)

2007-01-01T23:59:59.000Z

23

90.1 Prototype Building Models Warehouse (non-refrigerated) | Building  

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

Warehouse (non-refrigerated) Warehouse (non-refrigerated) The ASHRAE Standard 90.1 prototype building models were developed by Pacific Northwest National Laboratory in support of the U.S. Department of Energy's (DOE's) Building Energy Codes Program. These prototype buildings were derived from DOE's Commercial Reference Building Models. This suite of ASHRAE Standard 90.1 prototype buildings covers all the Reference Building types except supermarket, and also adds a new building prototype representing high-rise apartment buildings.The prototype models include 16 building types in 17 climate locations for ASHRAE Standards 90.1-2004, 90.1-2007 and 90.1-2010. This combination leads to a set of 816 building models (in EnergyPlus Version 6.0). Also included is a scorecard for each prototype building. The scorecard is a spreadsheet that summarizes the

24

Modeling language variability  

Science Conference Proceedings (OSTI)

A systematic way of defining variants of a modeling language is useful for adapting the language to domain or project specific needs. Variants can be obtained by adapting the syntax or semantics of the language. In this paper, we take a formal approach ...

Hans Grönniger; Bernhard Rumpe

2010-03-01T23:59:59.000Z

25

Module Development and Simulation of the Variable Refrigerant Flow Air Conditioning System under Cooling Conditions in Energyplus  

E-Print Network (OSTI)

As a high-efficiency air conditioning scheme, the variable refrigerant flow (VRF) air-conditioning system is finding its way into medium-sized office buildings. Based on a generic dynamic building energy simulation environment, EnergyPlus, a new module is developed and the energy usage of the VRF system is investigated. This paper compares the energy consumption of the VRF system with that of two conventional air-conditioning systems, namely, the variable air volume (VAV) system and the fan-coil plus fresh air (FPFA) system. A generic office building is used to accommodate the different types of heating, ventilating, and air conditioning (HVAC) systems. Our objective is to examine the energy consumption of the VRF system applied to office buildings and make suggestions for evaluating and making decisions on HVAC systems in the early stages of building design. Simulation results show that the energy-saving potential of the VRF system is expected to achieve 22.2 percent and 11.7 percent, compared to the VAV system and the FPFA system, respectively. An energy-usage breakdown of electricity end-users in various systems is also presented.

Zhou, Y.; Wu, J.; Wang, R.; Shiochi, S.

2006-01-01T23:59:59.000Z

26

Modeling of Solar-Powered Single-Effect Absorption Cooling System and Supermarket Refrigeration/HVAC System.  

E-Print Network (OSTI)

?? This thesis consists of two different research problems. In the first one, the aim is to model and simulate a solar-powered, single-effect, absorption refrigeration… (more)

Bahman, Ammar Mohammad Khalil

2011-01-01T23:59:59.000Z

27

Modeling of Solar-Powered Single-Effect Absorption Cooling System and Supermarket Refrigeration/HVAC System.  

E-Print Network (OSTI)

??This thesis consists of two different research problems. In the first one, the aim is to model and simulate a solar-powered, single-effect, absorption refrigeration system… (more)

Bahman, Ammar

2011-01-01T23:59:59.000Z

28

Kylteknik ("KYL")Kylteknik ("KYL") RefrigerationRefrigerationRefrigerationRefrigeration  

E-Print Network (OSTI)

of the tower An (earlier) alternative is to use a spray pond to cool water; disadvantages are a large areaRefrigerationRefrigerationRefrigeration coursecourse # 424503.0# 424503.0 v.v. 20122012 7. Air conditioning, cooling towersg, g Ron Zevenhoven Ã?Ã?bo, is the hi htemperature at which condensation begins when air is cooled at constant pressurecooled

Zevenhoven, Ron

29

Kylteknik ("KYL")Kylteknik ("KYL") RefrigerationRefrigerationRefrigerationRefrigeration  

E-Print Network (OSTI)

refrigeration processes (4 5) Vapor-compression refrigeration processes (4-5) Absorption refrigeration; Gas processing (O2, H2, CO2, LPG, LNG...) (3) Air conditioning, cooling towers, rg/pages/zon Air conditioning, cooling towers, food cooling and freezing (4) Heat pumps, heat pipes, special ww.sgisland.o p p

Zevenhoven, Ron

30

Kylteknik ("KYL")Kylteknik ("KYL") RefrigerationRefrigerationRefrigerationRefrigeration  

E-Print Network (OSTI)

.100.110.2 Typical refrigerant: R-134a, R- 600a and other hydrocarbons cture:http://1 Air-cooled condensing unit ncompressioisentropicwithprocess isentropicc realc t COP COP · The diagram gives some efficiency data from commercial vapour- 6 some efficiency data from commercial vapour compression refrigerators (T1 = TH, T2 = TL, data from 1976

Zevenhoven, Ron

31

Duracold Refrigeration Manufacturing: Order (2013-CE-5342) | Department of  

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

Duracold Refrigeration Manufacturing: Order (2013-CE-5342) Duracold Refrigeration Manufacturing: Order (2013-CE-5342) Duracold Refrigeration Manufacturing: Order (2013-CE-5342) April 25, 2013 DOE ordered Duracold Refrigeration Manufacturing Company, LLC to pay a $8,000 civil penalty after finding Duracold Refrigeration Manufacturing had failed to certify that certain models of walk-in cooler and freezer components comply with the applicable energy conservation standards. The Order adopted a Compromise Agreement, which reflected settlement terms between DOE and Duracold Refrigeration Manufacturing. Duracold Refrigeration Manufacturing: Order (2013-CE-5342) More Documents & Publications Duracold Refrigeration Manufacturing: Proposed Penalty (2013-CE-5342) North Star Refrigerator: Order (2013-CE-5355) Schott Gemtron: Order (2013-CE-5358

32

Thermal Analysis of Refrigeration Systems Used for Vaccine ...  

Science Conference Proceedings (OSTI)

... style refrigerator and a freezerless household refrigerator used ... possible that the nature of the cooling system and ... model simply do not cool the side ...

2012-08-02T23:59:59.000Z

33

Bond Graph Modeling Of Variable Structure Systems  

E-Print Network (OSTI)

The problem of describing variable structure models in a compact, object--oriented fashion is revisited and analyzed from the perspective of bond graph modeling. Traditionally, bond graphs have always been used to describe continuous-- time physical processes with a fixed structure. Yet, this paper shall demonstrate that bond graphs are equally suitable to describe variable structure models as fixed structure models. Moreover, a bond graph description of variable structure models can teach us a lot about the essential properties of variable structure models, properties that are not easily visible when other modeling approaches are taken. The paper discusses issues related to causality reassignment and conditional index changes as a consequence of switching in a physical system. Keywords: Bond graphs, variable structure system, computational causality, conditional index change, switching, object--oriented modeling, Dymola. INTRODUCTION When the causality strokes were added to the forme...

François E. Cellier; Martin Otter; Hilding Elmqvist

1995-01-01T23:59:59.000Z

34

Control system for heat exchangers fans in a refrigeration system  

Science Conference Proceedings (OSTI)

The paper presents a method for controlling evaporator and condenser fans in a refrigeration system. The refrigeration system includes a refrigerant circuit defined by a compressor, a condenser, a throttling device, and an evaporator. The system includes ... Keywords: controlling, fan, refrigeration system, variable frequency drive unit

Cristian Iosifescu; Valeriu Damian; C?lin Ciufudean

2010-05-01T23:59:59.000Z

35

Cospolich Refrigerator: Order (2013-CE-5314)  

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

DOE ordered Cospolich Refrigerator Co, Inc. to pay a $8,000 civil penalty after finding Cospolich Refrigerator had failed to certify that certain models of walk-in cooler and freezer components comply with the applicable energy conservation standards.

36

Grassmann Variables in Jordan Matrix Models  

E-Print Network (OSTI)

Here we demonstrate the emergence of Grassmann variables in matrix models based on the exceptional Jordan algebra. The Grassmann algebras are built naturally using the octonion algebra. We argue the appearance of Grassmann variables solidifies the relationship between supersymmetry and triality.

Michael Rios

2005-03-02T23:59:59.000Z

37

Cloud service selection based on variability modeling  

Science Conference Proceedings (OSTI)

The selection among Cloud services is a recent problem in research and practice. The diversity of decision-relevant criteria, configurability of Cloud services and the need to involve human decision-makers require holistic support through models, methodologies ... Keywords: cloud service selection, decision-making, feature modeling, variability modeling

Erik Wittern; Jörn Kuhlenkamp; Michael Menzel

2012-11-01T23:59:59.000Z

38

Superfluid thermodynamic cycle refrigerator  

DOE Patents (OSTI)

This invention is comprised of a cryogenic refrigerator which cools a heat source by cyclically concentrating and diluting the amount of [sup 3]He in a single phase [sup 3]He/[sup 4]He solution. The [sup 3]He in superfluid [sup 4]He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid [sup 3]He at an initial concentration in superfluid [sup 4]He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of [sup 4]He while restricting passage of [sup 3]He. The [sup 3]He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K.

Swift, G.W.; Kotsubo, V.Y.

1991-04-02T23:59:59.000Z

39

Superfluid thermodynamic cycle refrigerator  

DOE Patents (OSTI)

A cryogenic refrigerator cools a heat source by cyclically concentrating and diluting the amount of [sup 3]He in a single phase [sup 3]He-[sup 4]He solution. The [sup 3]He in superfluid [sup 4]He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid [sup 3]He at an initial concentration in superfluid [sup 4]He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of [sup 4]He while restricting passage of [sup 3]He. The [sup 3]He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K. 12 figs.

Swift, G.W.; Kotsubo, V.Y.

1992-12-22T23:59:59.000Z

40

Superfluid thermodynamic cycle refrigerator  

DOE Patents (OSTI)

This invention is comprised of a cryogenic refrigerator which cools a heat source by cyclically concentrating and diluting the amount of {sup 3}He in a single phase {sup 3}He/{sup 4}He solution. The {sup 3}He in superfluid {sup 4}He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid {sup 3}He at an initial concentration in superfluid {sup 4}He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of {sup 4}He while restricting passage of {sup 3}He. The {sup 3}He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K.

Swift, G.W.; Kotsubo, V.Y.

1991-04-02T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Superfluid thermodynamic cycle refrigerator  

DOE Patents (OSTI)

A cryogenic refrigerator cools a heat source by cyclically concentrating and diluting the amount of .sup.3 He in a single phase .sup.3 He-.sup.4 He solution. The .sup.3 He in superfluid .sup.4 He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid .sup.3 He at an initial concentration in superfluid .sup.4 He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of .sup.4 He while restricting passage of .sup.3 He. The .sup.3 He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K.

Swift, Gregory W. (Santa Fe, NM); Kotsubo, Vincent Y. (La Canada, CA)

1992-01-01T23:59:59.000Z

42

Japanese refrigerators field testing  

SciTech Connect

Residential refrigerators consume the equivalent of 1700 megawatts (MW) of baseload power in the Bonneville Power Administration (BPA) service area. Japanese manufacturers have designed refrigerator units that appear more energy efficient than some currently available American models. This report summarizes preliminary findings from field testing of 12 refrigerators of Japanese manufacture to evaluate annual kilowatt hour (kWh) use during actual operation. The units have also undergone laboratory testing sponsored by BPA at ETL Testing Laboratories, Inc. in Cortland, New York. A final report of the project -- due at the end of 1989 -- will correlate in detail the results of field and laboratory tests in comparison to performance ratings determined by the manufacturer.

Lou, A.T.

1989-03-01T23:59:59.000Z

43

Japanese Refrigerators Field Testing.  

SciTech Connect

Residential refrigerators consume the equivalent of 1700 megawatts (MW) of baseload power in the Bonneville Power Administration (BPA) service area. Japanese manufacturers have designed refrigerator units that appear more energy efficient than some currently available American models. This report summarizes preliminary findings from field testing of 12 refrigerators of Japanese manufacture to evaluate annual kilowatt hour (kWh) use during actual operation. The units have also undergone laboratory testing sponsored by BPA at ETL Testing Laboratories, Inc. in Cortland, New York. A final report of the project -- due at the end of 1989 -- will correlate in detail the results of field and laboratory tests in comparison to performance ratings determined by the manufacturer.

Lou, Albert T.

1989-03-01T23:59:59.000Z

44

Kylteknik ("KYL")Kylteknik ("KYL") RefrigerationRefrigerationRefrigerationRefrigeration  

E-Print Network (OSTI)

) and gives it off at higher ail.asp?article temperature (and pressure) and gives it off at higher temperature or no pressure changes Coolant for an engine: e:http://www 8.11.2012Ã?bo Akademi Univ - Thermal and Flow Engineering - Piispankatu 8, 20500 Turku 32/64 pressure changes. Coolant for an engine: not a refrigerant

Zevenhoven, Ron

45

Refrigerant directly cooled capacitors  

DOE Patents (OSTI)

The invention is a direct contact refrigerant cooling system using a refrigerant floating loop having a refrigerant and refrigeration devices. The cooling system has at least one hermetic container disposed in the refrigerant floating loop. The hermetic container has at least one electronic component selected from the group consisting of capacitors, power electronic switches and gating signal module. The refrigerant is in direct contact with the electronic component.

Hsu, John S. (Oak Ridge, TN); Seiber, Larry E. (Oak Ridge, TN); Marlino, Laura D. (Oak Ridge, TN); Ayers, Curtis W. (Kingston, TN)

2007-09-11T23:59:59.000Z

46

DOE Closes Investigation of Arcelik's Blomberg Refrigerator | Department of  

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

Arcelik's Blomberg Refrigerator Arcelik's Blomberg Refrigerator DOE Closes Investigation of Arcelik's Blomberg Refrigerator September 1, 2010 - 4:37pm Addthis The Department of Energy has closed its investigation into the energy efficiency of Arcelik's Blomberg refrigerator-freezer model # BRFB1450. The Department opened this investigation based on a complaint. DOE subpoenaed information from Arcelik, reviewed Arcelik's response, and performed its own testing of this model. Based on our investigation and test results, DOE has determined this model to be compliant with federal energy conservation standards. Notice of Compliance Determination Addthis Related Articles DOE Opens Three Investigations into Alleged Refrigerator Efficiency Violations DOE Closes Investigation of Whirlpool's Maytag Refrigerator

47

Fluorescent refrigeration  

DOE Patents (OSTI)

Fluorescent refrigeration is based on selective radiative pumping, using substantially monochromatic radiation, of quantum excitations which are then endothermically redistributed to higher energies. Ultimately, the populated energy levels radiatively deexcite emitting, on the average, more radiant energy than was initially absorbed. The material utilized to accomplish the cooling must have dimensions such that the exciting radiation is strongly absorbed, but the fluorescence may exit the material through a significantly smaller optical pathlength. Optical fibers and mirrored glasses and crystals provide this requirement. 6 figs.

Epstein, R.I.; Edwards, B.C.; Buchwald, M.I.; Gosnell, T.R.

1995-09-05T23:59:59.000Z

48

Thermal Analysis of Refrigeration Systems Used for Vaccine ...  

Science Conference Proceedings (OSTI)

... Is this refrigerator model suitable for frozen vaccine storage? Freezer thermostat dial set to midpoint position: vaccine vial temperatures ...

2012-08-02T23:59:59.000Z

49

ARTI refrigerant database  

Science Conference Proceedings (OSTI)

The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilitates access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alternative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.

Calm, J.M.

1996-07-01T23:59:59.000Z

50

ARTI refrigerant database  

Science Conference Proceedings (OSTI)

The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilities access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alternative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.

Calm, J.M. [Calm (James M.), Great Falls, VA (United States)] [Calm (James M.), Great Falls, VA (United States)

1999-01-01T23:59:59.000Z

51

ARTI refrigerant database  

Science Conference Proceedings (OSTI)

The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilitates access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alternative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.

Calm, J.M.

1996-11-15T23:59:59.000Z

52

Variable selection in nonparametric additive models  

E-Print Network (OSTI)

We consider a nonparametric additive model of a conditional mean function in which the number of variables and additive components may be larger than the sample size but the number of nonzero additive components is "small" relative to the sample size. The statistical problem is to determine which additive components are nonzero. The additive components are approximated by truncated series expansions with B-spline bases. With this approximation, the problem of component selection becomes that of selecting the groups of coefficients in the expansion. We apply the adaptive group Lasso to select nonzero components, using the group Lasso to obtain an initial estimator and reduce the dimension of the problem. We give conditions under which the group Lasso selects a model whose number of components is comparable with the underlying model, and the adaptive group Lasso selects the nonzero components correctly with probability approaching one as the sample size increases and achieves the optimal rate of convergence. Th...

Huang, Jian; Wei, Fengrong; 10.1214/09-AOS781

2010-01-01T23:59:59.000Z

53

Low-GWP Refrigerants Research Project | Department of Energy  

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

Emerging Technologies » Low-GWP Refrigerants Research Project Emerging Technologies » Low-GWP Refrigerants Research Project Low-GWP Refrigerants Research Project The U.S. Department of Energy is currently conducting research into low global warming potential (GWP) refrigerants. As concerns about climate change intensify, it is becoming increasingly clear that suitable low-GWP refrigerants will be needed for both new and existing residential and commercial heating, ventilation, air conditioning, and refrigeration (HVAC&R) equipment. Project Description This project seeks to develop alternative refrigerants for HVAC&R equipment. The overall environmental impacts of alternative refrigerants will be assessed using a life cycle climate performance model that accounts for direct emissions associated with refrigerant leaks and indirect

54

Modeling the Variability of Sydney Harbor Wind Measurements  

Science Conference Proceedings (OSTI)

The time-dependent behavior in the variability of wind measurements is investigated using bivariate generalized autoregressive conditional heteroscedastic models. These models express the current level of short-timescale wind variability in terms ...

Edward Cripps; William T. M. Dunsmuir

2003-08-01T23:59:59.000Z

55

Control method for mixed refrigerant based natural gas liquefier  

DOE Patents (OSTI)

In a natural gas liquefaction system having a refrigerant storage circuit, a refrigerant circulation circuit in fluid communication with the refrigerant storage circuit, and a natural gas liquefaction circuit in thermal communication with the refrigerant circulation circuit, a method for liquefaction of natural gas in which pressure in the refrigerant circulation circuit is adjusted to below about 175 psig by exchange of refrigerant with the refrigerant storage circuit. A variable speed motor is started whereby operation of a compressor is initiated. The compressor is operated at full discharge capacity. Operation of an expansion valve is initiated whereby suction pressure at the suction pressure port of the compressor is maintained below about 30 psig and discharge pressure at the discharge pressure port of the compressor is maintained below about 350 psig. Refrigerant vapor is introduced from the refrigerant holding tank into the refrigerant circulation circuit until the suction pressure is reduced to below about 15 psig, after which flow of the refrigerant vapor from the refrigerant holding tank is terminated. Natural gas is then introduced into a natural gas liquefier, resulting in liquefaction of the natural gas.

Kountz, Kenneth J. (Palatine, IL); Bishop, Patrick M. (Chicago, IL)

2003-01-01T23:59:59.000Z

56

Refrigeration system having standing wave compressor  

DOE Patents (OSTI)

A compression-evaporation refrigeration system, wherein gaseous compression of the refrigerant is provided by a standing wave compressor. The standing wave compressor is modified so as to provide a separate subcooling system for the refrigerant, so that efficiency losses due to flashing are reduced. Subcooling occurs when heat exchange is provided between the refrigerant and a heat pumping surface, which is exposed to the standing acoustic wave within the standing wave compressor. A variable capacity and variable discharge pressure for the standing wave compressor is provided. A control circuit simultaneously varies the capacity and discharge pressure in response to changing operating conditions, thereby maintaining the minimum discharge pressure needed for condensation to occur at any time. Thus, the power consumption of the standing wave compressor is reduced and system efficiency is improved.

Lucas, Timothy S. (Glen Allen, VA)

1992-01-01T23:59:59.000Z

57

ARTI Refrigerant Database  

Science Conference Proceedings (OSTI)

The Refrigerant Database consolidates and facilitates access to information to assist industry in developing equipment using alternative refrigerants. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.

Calm, J.M. [Calm (James M.), Great Falls, VA (United States)

1994-05-27T23:59:59.000Z

58

Literature survey of heat transfer enhancement techniques in refrigeration applications  

Science Conference Proceedings (OSTI)

A survey has been performed of the technical and patent literature on enhanced heat transfer of refrigerants in pool boiling, forced convection evaporation, and condensation. Extensive bibliographies of the technical literature and patents are given. Many passive and active techniques were examined for pure refrigerants, refrigerant-oil mixtures, and refrigerant mixtures. The citations were categorized according to enhancement technique, heat transfer mode, and tube or shell side focus. The effects of the enhancement techniques relative to smooth and/or pure refrigerants were illustrated through the discussion of selected papers. Patented enhancement techniques also are discussed. Enhanced heat transfer has demonstrated significant improvements in performance in many refrigerant applications. However, refrigerant mixtures and refrigerant-oil mixtures have not been studied extensively; no research has been performed with enhanced refrigerant mixtures with oil. Most studies have been of the parametric type; there has been inadequate examination of the fundamental processes governing enhanced refrigerant heat transfer, but some modeling is being done and correlations developed. It is clear that an enhancement technique must be optimized for the refrigerant and operating condition. Fundamental processes governing the heat transfer must be examined if models for enhancement techniques are to be developed; these models could provide the method to optimize a surface. Refrigerant mixtures, with and without oil present, must be studied with enhancement devices; there is too little known to be able to estimate the effects of mixtures (particularly NARMs) with enhanced heat transfer. Other conclusions and recommendations are offered.

Jensen, M.K.; Shome, B. [Rensselaer Polytechnic Inst., Troy, NY (United States). Dept. of Mechanical Engineering, Aeronautical Engineering and Mechanics

1994-05-01T23:59:59.000Z

59

Modeling Climate Variability in the Tropical Atlantic Atmosphere  

Science Conference Proceedings (OSTI)

Climate variability in the tropical Atlantic sector as represented in six atmospheric general circulation models is examined. On the annual mean, most simulations overestimate wind stress away from the equator although much of the variability can ...

Jiande Wang; James A. Carton

2003-12-01T23:59:59.000Z

60

Hybrid fuzzy-mechanistic models for addressing parameter variability  

Science Conference Proceedings (OSTI)

A simulation approach which integrates mechanistic models and fuzzy logic in order to accommodate parameter variability is developed and explored. The approach modifies a mechanistic model, such as a runoff model, for which the values of the parameters ... Keywords: Algal concentration modelling, Fuzzy logic, Model parameters, Modelling, Runoff modelling

Nicolas Lauzon; Barbara J. Lence

2008-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Intraseasonal Variability in a Two-Layer Model and Observations  

Science Conference Proceedings (OSTI)

A two-layer shallow-water model with R15 truncation and topographic forcing is used to study intraseasonal variability in the Northern Hemisphere’s (NH’s) extratropical atmosphere. The model’s variability is dominated by oscillations with average ...

Christian L. Keppenne; Steven L. Marcus; Masahide Kimoto; Michael Ghil

2000-04-01T23:59:59.000Z

62

Finite Element Modeling of Pharmaceutical Powder Compaction ...  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... of Lithium Battery Materials LiMPO4 (M = Mn, Fe, Co, and Ni): A Comparative ... Forming-Crush Simulation Optimization Using Internal State Variable Model.

63

The Quantum Absorption Refrigerator  

E-Print Network (OSTI)

A quantum absorption refrigerator driven by noise is studied with the purpose of determining the limitations of cooling to absolute zero. The model consists of a working medium coupled simultaneously to hot, cold and noise baths. Explicit expressions for the cooling power are obtained for Gaussian and Poisson white noise. The quantum model is consistent with the first and second laws of thermodynamics. The third law is quantified, the cooling power J_c vanishes as J_c proportional to T_c^{alpha}, when T_c approach 0, where alpha =d+1 for dissipation by emission and absorption of quanta described by a linear coupling to a thermal bosonic field, where d is the dimension of the bath.

Amikam Levy; Ronnie Kosloff

2011-09-04T23:59:59.000Z

64

Antarctic Bottom Water Variability in a Coupled Climate Model  

Science Conference Proceedings (OSTI)

The natural variability of the Weddell Sea variety of Antarctic Bottom Water (AABW) is examined in a long-term integration of a coupled climate model. Examination of passive tracer concentrations suggests that the model AABW is predominantly ...

Agus Santoso; Matthew H. England

2008-09-01T23:59:59.000Z

65

Indian Ocean Intraseasonal Variability in an Ocean General Circulation Model  

Science Conference Proceedings (OSTI)

The impact of atmospheric intraseasonal variability on the tropical Indian Ocean is examined with an ocean general circulation model (OGCM). The model is forced by observation-based wind stresses and surface heat fluxes from an atmospheric ...

A. Schiller; J. S. Godfrey

2003-01-01T23:59:59.000Z

66

Energy Efficient Operation of Ammonia Refrigeration Systems  

SciTech Connect

Ammonia refrigeration systems typically offer many energy efficiency opportunities because of their size and complexity. This paper develops a model for simulating single-stage ammonia refrigeration systems, describes common energy saving opportunities, and uses the model to quantify those opportunities. The simulation model uses data that are typically available during site visits to ammonia refrigeration plants and can be calibrated to actual consumption and performance data if available. Annual electricity consumption for a base-case ammonia refrigeration system is simulated. The model is then used to quantify energy savings for six specific energy efficiency opportunities; reduce refrigeration load, increase suction pressure, employ dual suction, decrease minimum head pressure set-point, increase evaporative condenser capacity, and reclaim heat. Methods and considerations for achieving each saving opportunity are discussed. The model captures synergistic effects that result when more than one component or parameter is changed. This methodology represents an effective method to model and quantify common energy saving opportunities in ammonia refrigeration systems. The results indicate the range of savings that might be expected from common energy efficiency opportunities.

Mohammed, Abdul Qayyum [University of Dayton, Ohio; Wenning, Thomas J [ORNL; Sever, Franc [University of Dayton, Ohio; Kissock, Professor Kelly [University of Dayton, Ohio

2013-01-01T23:59:59.000Z

67

ARTI refrigerant database  

Science Conference Proceedings (OSTI)

The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilitates access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alterative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern. The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air-conditioning and refrigeration equipment. The complete documents are not included, though some may be added at a later date. The database identifies sources of specific information on various refrigerants. It addresses lubricants including alkylbenzene, polyalkylene glycol, polyolester, and other synthetics as well as mineral oils. It also references documents addressing compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits. Incomplete citations or abstracts are provided for some documents. They are included to accelerate availability of the information and will be completed or replaced in future updates.

Calm, J.M.

1997-02-01T23:59:59.000Z

68

Regenerator for Magnetic Refrigerants  

Ames Laboratory researchers have developed a new magnetic material that can be used at low temperatures (sub liquid hydrogen) for magnetic refrigerators.

69

China Refrigerator Information Label  

E-Print Network (OSTI)

LBNL-246E China Refrigerator Information Label: Specification Development and Potential Impact Jianhong Cheng China National Institute of Standardization Tomoyuki Sakamoto The Institute of Energy

70

Chemically assisted mechanical refrigeration process  

DOE Patents (OSTI)

There is provided a chemically assisted mechanical refrigeration process including the steps of: mechanically compressing a refrigerant stream which includes vaporized refrigerant; contacting the refrigerant with a solvent in a mixer at a pressure sufficient to promote substantial dissolving of the refrigerant in the solvent in the mixer to form a refrigerant-solvent solution while concurrently placing the solution in heat exchange relation with a working medium to transfer energy to the working medium, said refrigerant-solvent solution exhibiting a negative deviation from Raoult's Law; reducing the pressure over the refrigerant-solvent solution in an evaporator to allow the refrigerant to vaporize and substantially separate from the solvent while concurrently placing the evolving refrigerant-solvent solution in heat exchange relation with a working medium to remove energy from the working medium to thereby form a refrigerant stream and a solvent stream; and passing the solvent and refrigerant stream from the evaporator. 5 figs.

Vobach, A.R.

1987-11-24T23:59:59.000Z

71

Chemically assisted mechanical refrigeration process  

DOE Patents (OSTI)

There is provided a chemically assisted mechanical refrigeration process including the steps of: mechanically compressing a refrigerant stream which includes vaporized refrigerant; contacting the refrigerant with a solvent in a mixer (11) at a pressure sufficient to promote substantial dissolving of the refrigerant in the solvent in the mixer (11) to form a refrigerant-solvent solution while concurrently placing the solution in heat exchange relation with a working medium to transfer energy to the working medium, said refrigerant-solvent solution exhibiting a negative deviation from Raoult's Law; reducing the pressure over the refrigerant-solvent solution in an evaporator (10) to allow the refrigerant to vaporize and substantially separate from the solvent while concurrently placing he evolving refrigerant-solvent solution in heat exchange relation with a working medium to remove energy from the working medium to thereby form a refrigerant stream and a solvent stream; and passing the solvent and refrigerant stream from the evaporator.

Vobach, Arnold R. (6006 Allentown Dr., Spring, TX 77379)

1987-01-01T23:59:59.000Z

72

Chemically assisted mechanical refrigeration process  

DOE Patents (OSTI)

There is provided a chemically assisted mechanical refrigeration process including the steps of: mechanically compressing a refrigerant stream which includes vaporized refrigerant; contacting the refrigerant with a solvent in a mixer (11) at a pressure sufficient to promote substantial dissolving of the refrigerant in the solvent in the mixer (11) to form a refrigerant-solvent solution while concurrently placing the solution in heat exchange relation with a working medium to transfer energy to the working medium, said refrigerant-solvent solution exhibiting a negative deviation from Raoult's Law; reducing the pressure over the refrigerant-solvent solution in an evaporator (10) to allow the refrigerant to vaporize and substantially separate from the solvent while concurrently placing the evolving refrigerant-solvent solution in heat exchange relation with a working medium to remove energy from the working medium to thereby form a refrigerant stream and a solvent stream; and passing the solvent and refrigerant stream from the evaporator.

Vobach, Arnold R. (6006 Allentown Dr., Spring, TX 77389)

1987-01-01T23:59:59.000Z

73

Chemically assisted mechanical refrigeration process  

DOE Patents (OSTI)

There is provided a chemically assisted mechanical refrigeration process including the steps of: mechanically compressing a refrigerant stream which includes vaporized refrigerant; contacting the refrigerant with a solvent in a mixer at a pressure sufficient to promote substantial dissolving of the refrigerant in the solvent in the mixer to form a refrigerant-solvent solution while concurrently placing the solution in heat exchange relation with a working medium to transfer energy to the working medium, said refrigerant-solvent solution exhibiting a negative deviation from Raoult's Law; reducing the pressure over the refrigerant-solvent solution in an evaporator to allow the refrigerant to vaporize and substantially separate from the solvent while concurrently placing the evolving refrigerant-solvent solution in heat exchange relation with a working medium to remove energy from the working medium to thereby form a refrigerant stream and a solvent stream; and passing the solvent and refrigerant stream from the evaporator. 5 figs.

Vobach, A.R.

1987-06-23T23:59:59.000Z

74

Asian Summer Monsoon Intraseasonal Variability in General Circulation Models  

SciTech Connect

The goals of this report are: (1) Analyze boreal summer Asian monsoon intraseasonal variability general circulation models--How well do the models represent the eastward and northward propagating components of the convection and how well do the models represent the interactive control that the western tropical Pacific rainfall exerts on the rainfall over India and vice-versa? (2) Role of air-sea interactions--prescribed vs. interactive ocean; and (3) Mean monsoon vs. variability.

Sperber, K R; Annamalai, H

2004-02-24T23:59:59.000Z

75

A Phase-Field Model for Deformation Twinning  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... of Lithium Battery Materials LiMPO4 (M = Mn, Fe, Co, and Ni): A Comparative ... Forming-Crush Simulation Optimization Using Internal State Variable Model.

76

Informatic Tools for Assessment of Data Completeness for Model ...  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... of Lithium Battery Materials LiMPO4 (M = Mn, Fe, Co, and Ni): A Comparative ... Forming-Crush Simulation Optimization Using Internal State Variable Model.

77

An Integrated Modeling and Experimental Study of Static Strain ...  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... of Lithium Battery Materials LiMPO4 (M = Mn, Fe, Co, and Ni): A Comparative ... Forming-Crush Simulation Optimization Using Internal State Variable Model.

78

Microstructure-Sensitive Modeling of Life-Limiting Fatigue Behavior ...  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... of Lithium Battery Materials LiMPO4 (M = Mn, Fe, Co, and Ni): A Comparative ... Forming-Crush Simulation Optimization Using Internal State Variable Model.

79

Multi-Time Scaling Crystal Plasticity FE Models Dwell Fatigue ...  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... of Lithium Battery Materials LiMPO4 (M = Mn, Fe, Co, and Ni): A Comparative ... Forming-Crush Simulation Optimization Using Internal State Variable Model.

80

ARTI Refrigerant Database  

Science Conference Proceedings (OSTI)

The Refrigerant Database consolidates and facilitates access to information to assist industry in developing equipment using alternative refrigerants. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern. The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air- conditioning and refrigeration equipment. The complete documents are not included, though some may be added at a later date. The database identifies sources of specific information on R-32, R-123, R-124, R- 125, R-134a, R-141b, R142b, R-143a, R-152a, R-290 (propane), R-717 (ammonia), ethers, and others as well as azeotropic and zeotropic blends of these fluids. It addresses polyalkylene glycol (PAG), ester, and other lubricants. It also references documents addressing compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits.

Calm, J.M.

1992-04-30T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Holographic Dark Energy Model with Modified Variable Chaplygin Gas  

E-Print Network (OSTI)

In this letter we consider a correspondence between holographic dark energy and variable modified Chaplygin gas to obtain a holographic dark energy model of the universe. The corresponding potential of the scalar field has been reconstructed which describes the modified variable Chaplygin gas. The stability of the holographic dark energy in this case is also discussed.

B. C. Paul

2010-06-17T23:59:59.000Z

82

Intraseasonal Variability in a Dry Atmospheric Model  

Science Conference Proceedings (OSTI)

A long integration of a primitive equation dry atmospheric model with time-independent forcing under boreal winter conditions is analyzed. A variety of techniques such as time filtering, space–time spectral analysis, and lag regressions are used ...

Hai Lin; Gilbert Brunet; Jacques Derome

2007-07-01T23:59:59.000Z

83

South Atlantic Multidecadal Variability in the Climate System Model  

Science Conference Proceedings (OSTI)

Strong multidecadal variability is detected in a 300-yr integration of the NCAR Climate System Model in the South Atlantic region, through the application of two signal recognition techniques: the multitaper method and singular spectrum analysis. ...

Ilana Wainer; Silvia A. Venegas

2002-06-01T23:59:59.000Z

84

Modeling Semidiurnal Internal Tide Variability in the Southern California Bight  

Science Conference Proceedings (OSTI)

The Regional Oceanic Modeling System (ROMS) is applied in a nested configuration with realistic forcing to the Southern California Bight (SCB) to analyze the variability in semidiurnal internal wave generation and propagation. The SCB has a ...

M. C. Buijsman; Y. Uchiyama; J. C. McWilliams; C. R. Hill-Lindsay

2012-01-01T23:59:59.000Z

85

Intraseasonal Variability in a Barotropic Model with Seasonal Forcing  

Science Conference Proceedings (OSTI)

It has recently been suggested that oscillatory topographic instability could contribute to low-frequency variability over the Northern Hemisphere midlatitudes. A barotropic potential vorticity model, with a hierarchy of forcing and topography ...

Christopher M. Strong; Fei-Fei Jin; Michael Ghil

1993-09-01T23:59:59.000Z

86

A Global Numerical Weather Prediction Model with Variable Resolution  

Science Conference Proceedings (OSTI)

A conformal transformation suggested by F. Schmidt is followed to implement a global spectral model with variable resolution. A conformal mapping is defined from a physical sphere (like the earth) to a transformed (computational) sphere. The ...

Vivek Hardiker

1997-01-01T23:59:59.000Z

87

Japanese Refrigerators : A Field Performance Analysis : Summary Report.  

SciTech Connect

Society generally expects Japanese refrigerators to be more energy efficient than their American-made counterparts. With increasing attention being focused on appliance energy efficiency, research into operating characteristics of Japanese refrigerators has gained importance. Other projects report the monitored energy use of certain models of Japanese refrigerators. In addition, laboratory tests determined energy consumption of certain refrigerators under controlled conditions. In 1987, Bonneville Power Administration (BPA) undertook a project to measure and analyze the energy consumption of 12 Japanese-made refrigerators in the Portland-Vancouver metropolitan area. This project's purpose was to collect field data on certain models and compare with that collected in other projects and laboratory tests. Japanese energy consumption figures fall 30--40% below those of DOE. This energy savings, if real, could substantially cut baseload power for utilities. Determining typical refrigerator energy use patterns and which environmental factors effect them helps utilities to forecast demand. 7 refs., 1 fig., 1 tab.

Short, John A.

1990-02-01T23:59:59.000Z

88

Refrigerated cryogenic envelope  

DOE Patents (OSTI)

An elongated cryogenic envelope including an outer tube and an inner tube coaxially spaced within said inner tube so that the space therebetween forms a vacuum chamber for holding a vacuum. The inner and outer tubes are provided with means for expanding or contracting during thermal changes. A shield is located in the vacuum chamber intermediate the inner and outer tubes; and, a refrigeration tube for directing refrigeration to the shield is coiled about at least a portion of the inner tube within the vacuum chamber to permit the refrigeration tube to expand or contract along its length during thermal changes within said vacuum chamber.

Loudon, John D. (Boulder, CO)

1976-11-16T23:59:59.000Z

89

DOE Opens Three Investigations into Alleged Refrigerator Efficiency  

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

Opens Three Investigations into Alleged Refrigerator Efficiency Opens Three Investigations into Alleged Refrigerator Efficiency Violations DOE Opens Three Investigations into Alleged Refrigerator Efficiency Violations April 12, 2010 - 7:27pm Addthis The Department of Energy has issued one subpoena and two data requests to three companies in response to allegations that the companies are selling refrigerator-freezers that failed to meet federal energy efficiency standards. Under the subpoena, Arçelik A.S, a Turkish Company is required to submit detailed information about the design, marketing and U.S. sales of its Blomberg brand refrigerator-freezer, model "BRFB1450." The Department also requested testing data from Whirlpool Corporation and Viking Range Corporation for two refrigerator-freezers that the companies

90

DOE Opens Three Investigations into Alleged Refrigerator Efficiency  

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

Opens Three Investigations into Alleged Refrigerator Efficiency Opens Three Investigations into Alleged Refrigerator Efficiency Violations DOE Opens Three Investigations into Alleged Refrigerator Efficiency Violations April 12, 2010 - 7:27pm Addthis The Department of Energy has issued one subpoena and two data requests to three companies in response to allegations that the companies are selling refrigerator-freezers that failed to meet federal energy efficiency standards. Under the subpoena, Arçelik A.S, a Turkish Company is required to submit detailed information about the design, marketing and U.S. sales of its Blomberg brand refrigerator-freezer, model "BRFB1450." The Department also requested testing data from Whirlpool Corporation and Viking Range Corporation for two refrigerator-freezers that the companies

91

Development of Low Global Warming Potential Refrigerant Solutions for Commercial Refrigeration Systems using a Life Cycle Climate Performance Design Tool  

SciTech Connect

Commercial refrigeration systems are known to be prone to high leak rates and to consume large amounts of electricity. As such, direct emissions related to refrigerant leakage and indirect emissions resulting from primary energy consumption contribute greatly to their Life Cycle Climate Performance (LCCP). In this paper, an LCCP design tool is used to evaluate the performance of a typical commercial refrigeration system with alternative refrigerants and minor system modifications to provide lower Global Warming Potential (GWP) refrigerant solutions with improved LCCP compared to baseline systems. The LCCP design tool accounts for system performance, ambient temperature, and system load; system performance is evaluated using a validated vapor compression system simulation tool while ambient temperature and system load are devised from a widely used building energy modeling tool (EnergyPlus). The LCCP design tool also accounts for the change in hourly electricity emission rate to yield an accurate prediction of indirect emissions. The analysis shows that conventional commercial refrigeration system life cycle emissions are largely due to direct emissions associated with refrigerant leaks and that system efficiency plays a smaller role in the LCCP. However, as a transition occurs to low GWP refrigerants, the indirect emissions become more relevant. Low GWP refrigerants may not be suitable for drop-in replacements in conventional commercial refrigeration systems; however some mixtures may be introduced as transitional drop-in replacements. These transitional refrigerants have a significantly lower GWP than baseline refrigerants and as such, improved LCCP. The paper concludes with a brief discussion on the tradeoffs between refrigerant GWP, efficiency and capacity.

Abdelaziz, Omar [ORNL; Fricke, Brian A [ORNL; Vineyard, Edward Allan [ORNL

2012-01-01T23:59:59.000Z

92

Thermoacoustic engines and refrigerators  

SciTech Connect

This report is a transcript of a practice lecture given in preparation for a review lecture on the operation of thermoacoustic engines and refrigerators. The author begins by a brief review of the thermodynamic principles underlying the operation of thermoacoustic engines and refrigerators. Remember from thermodynamics class that there are two kinds of heat engines, the heat engine or the prime mover which produces work from heat, and the refrigerator or heat pump that uses work to pump heat. The device operates between two thermal reservoirs at temperatures T{sub hot} and T{sub cold}. In the heat engine, heat flows into the device from the reservoir at T{sub hot}, produces work, and delivers waste heat into the reservoir at T{sub cold}. In the refrigerator, work flows into the device, lifting heat Q{sub cold} from reservoir at T{sub cold} and rejecting waste heat into the reservoir at T{sub hot}.

Swift, G.

1996-12-31T23:59:59.000Z

93

System design and simulation of constant temperature box using semiconductor refrigeration device  

Science Conference Proceedings (OSTI)

This paper presents the variation law of temperature in three-dimensional space, which is cooled by the refrigeration provided by the cold side of a semiconductor. The mathematical model of the temperature field of the semiconductor refrigeration ... Keywords: constant temperature box, forced convection, mathematical modelling, numerical simulation, semiconductor refrigeration, system design

Hui Zhang; Kuang-Chao Fan; Jun Wang

2010-03-01T23:59:59.000Z

94

High temperature refrigerator  

SciTech Connect

A high temperature magnetic refrigerator which uses a Stirling-like cycle in which rotating magnetic working material is heated in zero field and adiabatically magnetized, cooled in high field, then adiabatically demagnetized. During this cycle said working material is in heat exchange with a pumped fluid which absorbs heat from a low temperature heat source and deposits heat in a high temperature reservoir. The magnetic refrigeration cycle operates at an efficiency 70% of Carnot.

Steyert, Jr., William A. (Los Alamos, NM)

1978-01-01T23:59:59.000Z

95

Phase-Field Modeling of Microstructure Evolution for Ni-Base ...  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... of Lithium Battery Materials LiMPO4 (M = Mn, Fe, Co, and Ni): A Comparative ... Forming-Crush Simulation Optimization Using Internal State Variable Model.

96

EnergyPlus Analysis Capabilities for Use in California Building Energy Efficiency Standards Development and Compliance Calculations  

E-Print Network (OSTI)

7 Variable Refrigerant Flowto EnergyPlus. Variable Refrigerant Flow Systems The ACMcapability to model variable refrigerant flow (VRF) systems

Hong, Tianzhen

2009-01-01T23:59:59.000Z

97

Solar absorption refrigeration system using new working fluid pairs  

Science Conference Proceedings (OSTI)

Absorption refrigeration systems powered by solar energy increasingly attract research interests in the last years. In this study, thermodynamic analyses for different working fluid pairs are performed. A computer simulation model has been developed ... Keywords: NH3-LiNO3, absorption, crystallization, generator, performance, refrigeration, solar energy

Jasim M. Abdulateef; Kamaruzzaman Sopian; M. A. Alghoul; Mohd Yusof Sulaiman; Azami Zaharim; Ibrahim Ahmad

2008-02-01T23:59:59.000Z

98

Description and validation of a computer based refrigeration system simulator  

Science Conference Proceedings (OSTI)

This paper describes and evaluates the validation of a novel software package which simulates the transient and steady-state operation of whole refrigeration systems of the type used for the storage and processing of food. This software allows practitioners ... Keywords: Computer simulation, Food processing, Modelling, Refrigeration

I. W. Eames; T. Brown; J. A. Evans; G. G. Maidment

2012-07-01T23:59:59.000Z

99

Non-intrusive refrigerant charge indicator - Energy ...  

... -phase refrigerant line section. The measured temperature can be used to determine the refrigerant charge status of an HVAC system, ...

100

Demand Response Opportunities in Industrial Refrigerated Warehouses...  

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

Demand Response Opportunities in Industrial Refrigerated Warehouses in California Title Demand Response Opportunities in Industrial Refrigerated Warehouses in California...

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

DOE Closes Investigation of Whirlpool's Maytag Refrigerator | Department of  

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

Closes Investigation of Whirlpool's Maytag Refrigerator Closes Investigation of Whirlpool's Maytag Refrigerator DOE Closes Investigation of Whirlpool's Maytag Refrigerator July 8, 2010 - 3:12pm Addthis The Department of Energy has closed its investigation into the energy efficiency of Whirlpool's Maytag refrigerator-freezer model "MSD2578VE." The Department opened this investigation and requested testing data from Whirlpool based on a complaint (April 12, 2010, "DOE Opens Three Investigations into Alleged Refrigerator Efficiency Violations"). After reviewing the data and testing this model, the Department has found the model to be compliant with the applicable efficiency standards and has closed the investigation. The Department takes credible allegations seriously and will continue to initiate investigations on products that are

102

DOE Closes Investigation of Whirlpool's Maytag Refrigerator | Department of  

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

of Whirlpool's Maytag Refrigerator of Whirlpool's Maytag Refrigerator DOE Closes Investigation of Whirlpool's Maytag Refrigerator July 8, 2010 - 3:12pm Addthis The Department of Energy has closed its investigation into the energy efficiency of Whirlpool's Maytag refrigerator-freezer model "MSD2578VE." The Department opened this investigation and requested testing data from Whirlpool based on a complaint (April 12, 2010, "DOE Opens Three Investigations into Alleged Refrigerator Efficiency Violations"). After reviewing the data and testing this model, the Department has found the model to be compliant with the applicable efficiency standards and has closed the investigation. The Department takes credible allegations seriously and will continue to initiate investigations on products that are

103

ARTI Refrigerant Database  

SciTech Connect

The Refrigerant Database consolidates and facilitates access to information to assist industry in developing equipment using alternative refrigerants. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern. The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air-conditioning and refrigeration equipment. The complete documents are not included. The database identifies sources of specific information on R-32, R-123, R-124, R-125, R-134, R-134a, R-141b, R-142b, R-143a, R-152a, R-245ca, R-290 (propane), R-717 (ammonia), ethers, and others as well as azeotropic and zeotropic blends of these fluids. It addresses lubricants including alkylbenzene, polyalkylene glycol, ester, and other synthetics as well as mineral oils. It also references documents addressing compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits. Incomplete citations or abstracts are provided for some documents to accelerate availability of the information and will be completed or replaced in future updates.

Cain, J.M. (Calm (James M.), Great Falls, VA (United States))

1993-04-30T23:59:59.000Z

104

International Refrigeration: Proposed Penalty (2012-CE-1510)  

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

International Refrigeration Products International Refrigeration Products (room air conditioners) ) ) ) ) ) Case Number: 2012-CE-1510 NOTICE OF PROPOSED CIVIL PENALTY Date issued: July 9, 2012 Number of alleged violations: 5475 (365 days, 15 models) Maximum possible assessment: $1,095,000 Proposed civil penalty: $109,500 The U.S. Department of Energy ("DOE") Office of the General Counsel, Office of Enforcement, alleges that International Refrigeration Products ("IRP") has violated cettain provisions of the Energy Policy and Conservation Act, 42 U.S.C. § 6291 et seq. ("the Act"), and 10 C.P.R. § 429.12. Specifically, DOE alleges: 1. IRP has manufactured 1 a variety of Sea Breeze brand room air conditioners, including basic models WA46YR, WA48YRX, WA410YRX, WA412YRX, WH418ZRX,

105

Modeling the Variability of the Greater Agulhas Current System  

Science Conference Proceedings (OSTI)

An eddy-permitting, regional ocean model has been used to examine the variability in the source regions of the Agulhas Current on a range of time scales. These source regions are the East Madagascar Current, the flow through the Mozambique ...

J. C. Hermes; C. J. C. Reason; J. R. E. Lutjeharms

2007-07-01T23:59:59.000Z

106

Decadal Variability in a Simplified Wind-Driven Ocean Model  

Science Conference Proceedings (OSTI)

The impact of an unsteady wind forcing on oceanic low-frequency variability is conceptually studied using a reduced-gravity shallow-water model. A time-averaged wind forcing and a simple ocean–atmosphere coupling is completed by a stochastic ...

Philip Sura; Frank Lunkeit; Klaus Fraedrich

2000-08-01T23:59:59.000Z

107

Proceedings: Commercial Refrigeration Research Workshop  

Science Conference Proceedings (OSTI)

Improving refrigeration systems for commercial use can enhance both utility load factors and supermarket profits. This workshop has pinpointed research needs in commercial refrigeration and systems integration for a supermarket environment.

1984-10-01T23:59:59.000Z

108

A single dimensionless variable for solar chimney power plant modeling  

Science Conference Proceedings (OSTI)

The solar chimney power plant is a relatively new technology for generating electricity from solar energy. In this paper dimensional analysis is used together with engineering intuition to combine eight primitive variables into only one dimensionless variable that establishes a dynamic similarity between a prototype and its scaled models. Three physical configurations of the plant were numerically tested for similarity: fully geometrically similar, partially geometrically similar, and dissimilar types. The values of the proposed dimensionless variable for all these cases were found to be nominally equal to unity. The value for the physical plant actually built and tested previously was also evaluated and found to be about the same as that of the numerical simulations, suggesting the validity of the proposition. The physical meaning of this dimensionless (similarity) variable is also interpreted; and the connection between the Richardson number and this new variable was found. It was found also that, for a fixed solar heat flux, different-sized models that are fully or partially geometrically similar share an equal excess temperature across the roof outlet. (author)

Koonsrisuk, Atit; Chitsomboon, Tawit [School of Mechanical Engineering, Institute of Engineering, Suranaree University of Technology, Muang District, Nakhon Ratchasima 30000 (Thailand)

2009-12-15T23:59:59.000Z

109

COLD STORAGE DESIGN REFRIGERATION EQUIPMENT  

E-Print Network (OSTI)

COLD STORAGE DESIGN AND REFRIGERATION EQUIPMENT REFRIGERATION OF FISH - PART 1 \\ "..\\- ,,, T I Fishery Leaflet 427 Washington 25, D. C. June 1956 REFRIGERATION OF FISH - PART em; COlD STORAGE DESIGN · · · · · 18 Specific design features 0 0 · · · · · · · · · · · · · · 19 Refrigerated surfaces 0 · · 0 0 0 · 0

110

Solar powered refrigeration apparatus  

SciTech Connect

Solar powered refrigeration apparatus is disclosed in which an absorption refrigeration system is operated directly by solar energy. One end of a heat pipe is thermally connected to the boiler of the absorption refrigeration system, and a solar collector is thermally coupled to the other remote end of the heat pipe. The heat pipe is a sealed, evacuated metal tube partially filled with water. The solar collector is a double walled glass vacuum tube with a central axial opening for accommodating the remote end of the heat pipe. Heat energy collected by the solar collector boils the water in the heat pipe to subsequently condense in the area of the boiler thus transferring heat energy along the heat pipe to the boiler. The heat pipe is installed sloping downwardly away from the boiler to permit the return of condensate down the pipe to the solar collector area thus permitting continuous operation.

Theakston, F.H.

1982-12-07T23:59:59.000Z

111

Adsorption Refrigeration System  

SciTech Connect

Adsorption refrigeration is an environmentally friendly cooling technology which could be driven by recovered waste heat or low-grade heat such as solar energy. In comparison with absorption system, an adsorption system has no problems such as corrosion at high temperature and salt crystallization. In comparison with vapor compression refrigeration system, it has the advantages of simple control, no moving parts and less noise. This paper introduces the basic theory of adsorption cycle as well as the advanced adsorption cycles such as heat and mass recovery cycle, thermal wave cycle and convection thermal wave cycle. The types, characteristics, advantages and drawbacks of different adsorbents used in adsorption refrigeration systems are also summarized. This article will increase the awareness of this emerging cooling technology among the HVAC engineers and help them select appropriate adsorption systems in energy-efficient building design.

Wang, Kai [ORNL; Vineyard, Edward Allan [ORNL

2011-01-01T23:59:59.000Z

112

ARTI Refrigerant Database  

Science Conference Proceedings (OSTI)

The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air- conditioning and refrigeration equipment. The database identifies sources of specific information on R-32, R-123, R-124, R-125, R-134, R-134a, R-141b, R-142b, R-143a, R-152a, R-245ca, R-290 (propane), R- 717 (ammonia), ethers, and others as well as azeotropic and zeotropic and zeotropic blends of these fluids. It addresses lubricants including alkylbenzene, polyalkylene glycol, ester, and other synthetics as well as mineral oils. It also references documents on compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits. A computerized version is available that includes retrieval software.

Calm, J.M.

1992-11-09T23:59:59.000Z

113

Refrigerator recycling and CFCs  

SciTech Connect

Utility-sponsored refrigerator and freezer pick-up programs have removed almost 900,000 inefficient appliances from the North American electric grid to date. While the CFC-12 refrigerant from the discarded appliances is typically removed and recycled, in all but a few programs the CFC-11 in the foam insulation is not. About a quarter-billion pounds of CFC-11 are banked in refrigerator foam in the United States. Release of this ``bank`` of CFC, combined with that from foam insulation used in buildings, will be the largest source of future emissions if preventive measures are not taken. Methods exist to recover the CFC for reuse or to destroy it by incineration. The task of recycling or destroying the CFCs and other materials from millions of refrigerators is a daunting challenge, but one in which utilities can play a leadership role. E Source believes that utilities can profitably serve as the catalyst for public-private partnerships that deliver comprehensive refrigerator recycling. Rather than treating such efforts solely as a DSM resource acquisition, utilities could position these programs as a multifaceted service delivery that offers convenient appliance removal for homeowners, a solid waste minimization service for landfills, a source of recycled materials for industry, and a CFC recovery and/or disposal service in support of the HVAC industry and society`s atmospheric protection goals and laws. Financial mechanisms could be developed through these public-private enterprises to ensure that utilities are compensated for the extra cost of fully recycling refrigerators, including the foam CFC.

Shepard, M.; Hawthorne, W.; Wilson, A.

1994-12-31T23:59:59.000Z

114

Low-temperature magnetic refrigerator  

DOE Patents (OSTI)

The invention relates to magnetic refrigeration and more particularly to low temperature refrigeration between about 4 and about 20 K, with an apparatus and method utilizing a belt of magnetic material passed in and out of a magnetic field with heat exchangers within and outside the field operably disposed to accomplish refrigeration.

Barclay, J.A.

1983-05-26T23:59:59.000Z

115

Modeling Agents that Exhibit Variable Performance in a Collaborative Setting  

E-Print Network (OSTI)

Abstract. In a collaborative environment, knowledge about collaborators ’ skills is an important factor when determining which team members should perform a task. However, this knowledge may be incomplete or uncertain. In this paper, we extend our ETAPP (Environment-Task-Agents-Policy-Protocol) collaboration framework by modeling team members that exhibit non-deterministic performance, and comparing two alternative ways of using these models to assign agents to tasks. Our simulation-based evaluation shows that performance variability has a large impact on task performance, and that task performance is improved by consulting agent models built from a small number of observations of agents’ recent performance. 1

Ingrid Zukerman; Christian Guttmann

2005-01-01T23:59:59.000Z

116

Interannual Tropical Rainfall Variability in General Circulation Model Simulations Associated with the Atmospheric Model Intercomparison Project  

Science Conference Proceedings (OSTI)

The interannual variability of rainfall over the Indian subcontinent, the African Sahel, and the Nordeste region of Brazil have been evaluated in 32 models for the period 1979–88 as part of the Atmospheric Model Intercomparison Project (AMIP). ...

K. R. Sperber; T. N. Palmer

1996-11-01T23:59:59.000Z

117

The Greenhouse Gas Protocol Initiative: GHG Emissions from Refrigeration  

Open Energy Info (EERE)

The Greenhouse Gas Protocol Initiative: GHG Emissions from Refrigeration The Greenhouse Gas Protocol Initiative: GHG Emissions from Refrigeration and Air Conditioning Jump to: navigation, search Tool Summary LAUNCH TOOL Name: The Greenhouse Gas Protocol Initiative: GHG Emissions from Refrigeration and Air Conditioning Agency/Company /Organization: World Resources Institute, World Business Council for Sustainable Development Sector: Energy, Climate Focus Area: Greenhouse Gas Phase: Determine Baseline, Evaluate Effectiveness and Revise as Needed Resource Type: Software/modeling tools User Interface: Spreadsheet Website: www.ghgprotocol.org/calculation-tools/all-tools Cost: Free References: Refrigerant Guide[1] The Greenhouse Gas Protocol tool for refrigeration is a free Excel spreadsheet calculator designed to calculate GHG emissions specifically

118

Modeling the Effect of Land Surface Evaporation Variability on Precipitation Variability. Part I: General Response  

Science Conference Proceedings (OSTI)

This is the first of a two-part article that investigates the impact of land surface evaporation variability on the interannual variability of precipitation and compares it with the impact caused by sea surface temperature variability. Previous ...

Oreste Reale; Paul Dirmeyer

2002-08-01T23:59:59.000Z

119

The smallest refrigerators can reach maximal efficiency  

E-Print Network (OSTI)

We investigate whether size imposes a fundamental constraint on the efficiency of small thermal machines. We analyse in detail a model of a small self-contained refrigerator consisting of three qubits. We show analytically that this system can reach the Carnot efficiency, thus demonstrating that there exists no complementarity between size and efficiency.

Paul Skrzypczyk; Nicolas Brunner; Noah Linden; Sandu Popescu

2010-09-04T23:59:59.000Z

120

Variable fuel tax models. [Revenue generated via 4 models for Alabama  

SciTech Connect

Four variable fuel tax models are investigated with respect to Alabama Highway Department operations. The Fixed Percentage Fuel Tax Model establishes the state gasoline tax as a constant percentage of the wholesale price of gasoline. The Price Index Economic Model pegs state fuel taxes to a ratio of price indexes. The Fuel Efficiency Tax Model relates the gasoline tax to the variables of Consumer Price Index and vehicle efficiency. The Sales Tax Model establishes a sales tax on the purchase of gasoline and motor fuel sold in the state. Estimates of the amount of revenue expected to be generated by each model are made. Advantages and disadvantages of each model are presented.

Vecellio, R.L.; Moore, R.K.

1977-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Decadal Variability in an Idealized Ocean Model and Its Sensitivity to Surface Boundary Conditions  

Science Conference Proceedings (OSTI)

Variability in a three-dimensional ocean model of idealized geometry is analyzed. The variability is induced in the model by adding a stochastic component to the surface buoyancy forcing. The influence of the surface thermal forcing on the model ...

A. Capotondi; W. R. Holland

1997-06-01T23:59:59.000Z

122

GEOCHEMICAL MODELING OF F AREA SEEPAGE BASIN COMPOSITION AND VARIABILITY  

SciTech Connect

From the 1950s through 1989, the F Area Seepage Basins at the Savannah River Site (SRS) received low level radioactive wastes resulting from processing nuclear materials. Discharges of process wastes to the F Area Seepage Basins followed by subsequent mixing processes within the basins and eventual infiltration into the subsurface resulted in contamination of the underlying vadose zone and downgradient groundwater. For simulating contaminant behavior and subsurface transport, a quantitative understanding of the interrelated discharge-mixing-infiltration system along with the resulting chemistry of fluids entering the subsurface is needed. An example of this need emerged as the F Area Seepage Basins was selected as a key case study demonstration site for the Advanced Simulation Capability for Environmental Management (ASCEM) Program. This modeling evaluation explored the importance of the wide variability in bulk wastewater chemistry as it propagated through the basins. The results are intended to generally improve and refine the conceptualization of infiltration of chemical wastes from seepage basins receiving variable waste streams and to specifically support the ASCEM case study model for the F Area Seepage Basins. Specific goals of this work included: (1) develop a technically-based 'charge-balanced' nominal source term chemistry for water infiltrating into the subsurface during basin operations, (2) estimate the nature of short term and long term variability in infiltrating water to support scenario development for uncertainty quantification (i.e., UQ analysis), (3) identify key geochemical factors that control overall basin water chemistry and the projected variability/stability, and (4) link wastewater chemistry to the subsurface based on monitoring well data. Results from this study provide data and understanding that can be used in further modeling efforts of the F Area groundwater plume. As identified in this study, key geochemical factors affecting basin chemistry and variability included: (1) the nature or chemistry of the waste streams, (2) the open system of the basins, and (3) duration of discharge of the waste stream types. Mixing models of the archetype waste streams indicated that the overall basin system would likely remain acidic much of the time. Only an extended periods of predominantly alkaline waste discharge (e.g., >70% alkaline waste) would dramatically alter the average pH of wastewater entering the basins. Short term and long term variability were evaluated by performing multiple stepwise modeling runs to calculate the oscillation of bulk chemistry in the basins in response to short term variations in waste stream chemistry. Short term (1/2 month and 1 month) oscillations in the waste stream types only affected the chemistry in Basin 1; little variation was observed in Basin 2 and 3. As the largest basin, Basin 3 is considered the primary source to the groundwater. Modeling showed that the fluctuation in chemistry of the waste streams is not directly representative of the source term to the groundwater (i.e. Basin 3). The sequence of receiving basins and the large volume of water in Basin 3 'smooth' or nullify the short term variability in waste stream composition. As part of this study, a technically-based 'charge-balanced' nominal source term chemistry was developed for Basin 3 for a narrow range of pH (2.7 to 3.4). An example is also provided of how these data could be used to quantify uncertainty over the long term variations in waste stream chemistry and hence, Basin 3 chemistry.

Millings, M.; Denham, M.; Looney, B.

2012-05-08T23:59:59.000Z

123

DOE Testing Reveals Samsung Refrigerator Does Not Meet Energy Star  

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

Testing Reveals Samsung Refrigerator Does Not Meet Energy Star Testing Reveals Samsung Refrigerator Does Not Meet Energy Star Requirements DOE Testing Reveals Samsung Refrigerator Does Not Meet Energy Star Requirements March 16, 2010 - 4:28pm Addthis DOE-initiated testing has revealed that a Samsung refrigerator (model RF26VAB), which the company had claimed was Energy Star compliant, consumed more energy than permitted by the Energy Star program. Test results for the Samsung model at issue show that, when tested in accordance with DOE's test procedure, it consumed between 7 and 11.4 percent more energy than the Energy Star requirement. Samsung is no longer manufacturing this model, although it may still be available from some retail outlets. Based on this testing, DOE is referring Samsung Model RF26VAB to the U.S.

124

Compact acoustic refrigerator  

DOE Patents (OSTI)

This invention is comprised of a compact acoustic refrigeration system that actively cools components, e.g., electrical circuits, in a borehole environment. An acoustic engine includes first thermodynamic elements for generating a standing acoustic wave in a selected medium. An acoustic refrigerator includes second thermodynamic elements located in the standing wave for generating a relatively cold temperature at a first end of the second thermodynamic elements and a relatively hot temperature at a second end of the second thermodynamic elements. A resonator volume cooperates with the first and second thermodynamic elements to support the standing wave. To accommodate the high heat fluxes required for heat transfer to/from the first and second thermodynamic elements, first heat pipes transfer heat from the heat load to the second thermodynamic elements and second heat pipes transfer heat from first and second thermodynamic elements to the borehole environment.

Bennett, G.A.

1991-12-31T23:59:59.000Z

125

Compact acoustic refrigerator  

DOE Patents (OSTI)

A compact acoustic refrigeration system actively cools components, e.g., electrical circuits, in a borehole environment. An acoustic engine includes first thermodynamic elements for generating a standing acoustic wave in a selected medium. An acoustic refrigerator includes second thermodynamic elements located in the standing wave for generating a relatively cold temperature at a first end of the second thermodynamic elements and a relatively hot temperature at a second end of the second thermodynamic elements. A resonator volume cooperates with the first and second thermodynamic elements to support the standing wave. To accommodate the high heat fluxes required for heat transfer to/from the first and second thermodynamic elements, first heat pipes transfer heat from the heat load to the second thermodynamic elements and second heat pipes transfer heat from first and second thermodynamic elements to the borehole environment. 18 figs.

Bennett, G.A.

1992-11-24T23:59:59.000Z

126

Compact acoustic refrigerator  

DOE Patents (OSTI)

A compact acoustic refrigeration system actively cools components, e.g., electrical circuits (22), in a borehole environment. An acoustic engine (12, 14) includes first thermodynamic elements (12) for generating a standing acoustic wave in a selected medium. An acoustic refrigerator (16, 26, 28) includes second thermodynamic elements (16) located in the standing wave for generating a relatively cold temperature at a first end of the second thermodynamic elements (16) and a relatively hot temperature at a second end of the second thermodynamic elements (16). A resonator volume (18) cooperates with the first and second thermodynamic elements (12, 16) to support the standing wave. To accommodate the high heat fluxes required for heat transfer to/from the first and second thermodynamic elements (12, 16), first heat pipes (24, 26) transfer heat from the heat load (22) to the second thermodynamic elements (16) and second heat pipes (28, 32) transfer heat from first and second thermodynamic elements (12, 16) to the borehole environment.

Bennett, Gloria A. (Los Alamos, NM)

1992-01-01T23:59:59.000Z

127

Multilayer Thermionic Refrigeration  

DOE Green Energy (OSTI)

A review is presented of our program to construct an efficient solid state refrigerator based on thermionic emission of electrons over periodic barriers in the solid. The experimental program is to construct a simple device with one barrier layer using a three layers: metal-semiconductor-metal. The theoretical program is doing calculations to determine: (i) the optimal layer thickness, and (ii) the thermal conductivity.

Mahan, G.D.

1999-08-30T23:59:59.000Z

128

Energy Efficiency and Environmental Impact Analyses of Supermarket Refrigeration Systems  

SciTech Connect

This paper presents energy and life cycle climate performance (LCCP) analyses of a variety of supermarket refrigeration systems to identify designs that exhibit low environmental impact and high energy efficiency. EnergyPlus was used to model refrigeration systems in a variety of climate zones across the United States. The refrigeration systems that were modeled include the traditional multiplex DX system, cascade systems with secondary loops and the transcritical CO2 system. Furthermore, a variety of refrigerants were investigated, including R-32, R-134a, R-404A, R-1234yf, R-717, and R-744. LCCP analysis was used to determine the direct and indirect carbon dioxide emissions resulting from the operation of the various refrigeration systems over their lifetimes. Our analysis revealed that high-efficiency supermarket refrigeration systems may result in up to 44% less energy consumption and 78% reduced carbon dioxide emissions compared to the baseline multiplex DX system. This is an encouraging result for legislators, policy makers and supermarket owners to select low emission, high-efficiency commercial refrigeration system designs for future retrofit and new projects.

Fricke, Brian A [ORNL; Bansal, Pradeep [ORNL; Zha, Shitong [Hillphoenix

2013-01-01T23:59:59.000Z

129

Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants  

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

Thermodynamic Evaluation of Thermodynamic Evaluation of Low-GWP Refrigerants Mark O. McLinden National Institute of Standards and Technology markm@boulder.nist.gov; 303-497-3580 April 3, 2013 Optimization Fluid Modeling Cycle Modeling Final Candidates Optimum Thermo Parameters 2 | Building Technologies Office eere.energy.gov Purpose & Objectives Problem Statement: HFC refrigerants face restrictions: U.S./Canada/Mexico proposal to Montreal Protocol (85 % cut) EU regulations likely on all application areas (79 % cut)

130

Improving the energy efficiency of refrigerators in India  

Science Conference Proceedings (OSTI)

Five state-of-the-art, production refrigerators from different manufacturers in India were subjected to a variety of appliance rating and performance evaluation test procedures in an engineering laboratory. Cabinet heat loss, compressor calorimeter, high-ambient pull-down, and closed-door energy consumption tests were performed on each unit to assess the current status of commercially available Indian refrigerators and refrigerator component efficiencies. Daily energy consumption tests were performed at nominal line voltages and at 85% and 115% of nominal voltage to assess the effect of grid voltage variations. These test results were also used to indicate opportunities for effective improvements in energy efficiency. A widely distributed ``generic`` computer model capable of simulating single-door refrigerators with a small interior freezer section was used to estimate cabinet heat loss rates and closed door energy consumption values from basic cabinet and refrigeration circuit inputs. This work helped verify the model`s accuracy and potential value as a tool for evaluating the energy impact of proposed design options. Significant differences ranging from 30 to 90% were seen in the measured performance criterion for these ``comparable`` refrigerators suggesting opportunities for improvements in individual product designs. Modeled cabinet heat loadings differed from experimentally extrapolated values in a range from 2--29%, and daily energy consumption values estimated by the model differed from laboratory data by as little as 3% or as much as 25%, which indicates that refinement of the model may be needed for this single-door refrigerator type. Additional comparisons of experimentally measured performance criteria such as % compressor run times and compressor cycling rates to modeled results are given. The computer model is used to evaluate the energy saving impact of several modest changes to the basic Indian refrigerator design.

Sand, J.R.; Vineyard, E.A. [Oak Ridge National Lab., TN (United States); Bohman, R.H. [Consulting Engineer, Cedar Rapids, IA (United States)

1995-04-01T23:59:59.000Z

131

Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants  

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

Thermodynamic Evaluation of Thermodynamic Evaluation of Low-GWP Refrigerants Mark O. McLinden National Institute of Standards and Technology markm@boulder.nist.gov; 303-497-3580 April 3, 2013 Optimization Fluid Modeling Cycle Modeling Final Candidates Optimum Thermo Parameters 2 | Building Technologies Office eere.energy.gov Purpose & Objectives Problem Statement: HFC refrigerants face restrictions: U.S./Canada/Mexico proposal to Montreal Protocol (85 % cut) EU regulations likely on all application areas (79 % cut)

132

Vaccine refrigerator testing. Final report  

SciTech Connect

For the Central American Health Clinic Project initiated in 1986, Sandia National Laboratories and the Florida Solar Energy Center recognized the need for a test and evaluation program for vaccine refrigeration systems. At the Florida Solar Energy Center, side-by-side testing of three photovoltaic powered vaccine refrigerators began in 1987. The testing was expanded in 1988 to include a kerosene absorption refrigerator. This report presents observations, conclusions, and recommendations derived from testing the four vaccine refrigeration systems. Information is presented pertaining to the refrigerators, photovoltaic arrays, battery subsystems, charge controllers, and user requirements. This report should be of interest to designers, manufacturers, installers, and users of photovoltaic-powered vaccine refrigeration systems and components.

Ventre, G.G. [Univ. of Central Florida, Orlando, FL (United States); Kilfoyle, D.; Marion, B. [Florida Solar Energy Center, Cape Canaveral, FL (United States)

1990-06-01T23:59:59.000Z

133

Variables et categories grammaticales dans un modele ariane  

Science Conference Proceedings (OSTI)

Toutes tes catégories grammaticales utilisées dans un modéle de traduction ariane sont formalisées et codées de faç mnémonique en tant que variables et valeurs de variables. L'ensemble des variables d'un ...

Jean-Phillippe Guilbaud

1986-08-01T23:59:59.000Z

134

A Quasi-Three-Dimensional Variably Saturated Groundwater Flow Model for Climate Modeling  

Science Conference Proceedings (OSTI)

In this study, a quasi-three-dimensional, variably saturated groundwater flow model was developed by approximately dividing the three-dimensional soil water and groundwater flow into an unsaturated vertical soil water flow and a horizontal ...

Zhenghui Xie; Zhenhua Di; Zhendong Luo; Qian Ma

2012-02-01T23:59:59.000Z

135

Magnetic Refrigeration - Programmaster.org  

Science Conference Proceedings (OSTI)

Aug 6, 2013 ... Magnetic Refrigeration a 21st Century Highly Efficient and Green Cooling .... In order to advance their incorporation in prototypes and industrial ...

136

NICE3: Industrial Refrigeration System  

SciTech Connect

Energy Concepts has developed an absorption-augmented system as a cost-effective means of achieving more cooling capacity with a substantial reduction in energy consumption and greenhouse gas emissions for industrial refrigeration. It cuts fuel consumption by 30% by combining an internal combustion engine with a mechanical compression refrigeration system and an absorption refrigeration system. The absorption system is powered by engine waste heat. Conventional industrial refrigeration uses mechanical vapor compression, powered by electric motors, which results in higher energy costs. By the year 2010, the new system could cut fuel consumption by 19 trillion Btu and greenhouse emissions by more than 1 million tons per year.

Simon, P.

1999-09-29T23:59:59.000Z

137

Measurement and Modeling of Solar and PV Output Variability: Preprint  

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

Measurement and Modeling of Measurement and Modeling of Solar and PV Output Variability Preprint M. Sengupta To be presented at SOLAR 2011 Raleigh, North Carolina May 17-21, 2011 Conference Paper NREL/CP-5500-51105 April 2011 NOTICE The submitted manuscript has been offered by an employee of the Alliance for Sustainable Energy, LLC (Alliance), a contractor of the US Government under Contract No. DE-AC36-08GO28308. Accordingly, the US Government and Alliance retain a nonexclusive royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for US Government purposes. This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty,

138

Observational Constraints of New Variable Modified Chaplygin Gas Model  

E-Print Network (OSTI)

Assuming the flat FRW universe in Einstein's gravity filled with New Variable Modified Chaplygin gas (NVMCG) dark energy and dark matter having negligible pressure. In this research work we analyze the viability on the basis of recent observation. Hubble parameter $H$ is expressed in terms of the observable parameters $H_0$, $\\Omega_m^0$ and the model parameters $A_0$, $B_0$, $C_0$, $m$, $n$, $\\alpha$ and the red shift parameter $z$. Here we find a best fitted parameter range of $A_0$, $B_0$ keeping $0\\leq \\alpha \\leq 1$ and using Stern data set (12 points) by minimizing the $\\chi^2$ test at 66%, 90% and 99% confidence levels. Next we do the joint analysis with BAO and CMB observations. Again evaluating the distance modulus $\\mu(z)$ vs redshift ($z$) curve obtained in the model NVMCG with dark matter with the best fitted value of the parameters and comparing with that derived from the union2 compilation data.

Jhumpa Bhadra; Ujjal Debnath

2012-11-09T23:59:59.000Z

139

Commercial Refrigeration Equipment | Open Energy Information  

Open Energy Info (EERE)

Refrigeration Equipment Jump to: navigation, search TODO: Add description List of Commercial Refrigeration Equipment Incentives Retrieved from "http:en.openei.orgw...

140

Covered Product Category: Residential Refrigerators | Department of Energy  

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

Residential Refrigerators Residential Refrigerators Covered Product Category: Residential Refrigerators October 7, 2013 - 11:19am Addthis ENERGY STAR Qualified Products FEMP provides acquisition guidance across a variety of product categories, including residential refrigerators, which are an ENERGY STAR®-qualified product category. Federal laws and executive orders mandate that agencies meet these efficiency requirements in all procurement and acquisition actions that are not specifically exempted by law. Most manufacturers display the ENERGY STAR label on complying models. For a model not displaying this label, check the manufacturer's literature to determine if it meets the efficiency requirements outlined by ENERGY STAR. Performance Requirements for Federal Purchases For the most up-to-date efficiency levels required by ENERGY STAR, look for

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Covered Product Category: Residential Refrigerators | Department of Energy  

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

Refrigerators Refrigerators Covered Product Category: Residential Refrigerators October 7, 2013 - 11:19am Addthis ENERGY STAR Qualified Products FEMP provides acquisition guidance across a variety of product categories, including residential refrigerators, which are an ENERGY STAR®-qualified product category. Federal laws and executive orders mandate that agencies meet these efficiency requirements in all procurement and acquisition actions that are not specifically exempted by law. Most manufacturers display the ENERGY STAR label on complying models. For a model not displaying this label, check the manufacturer's literature to determine if it meets the efficiency requirements outlined by ENERGY STAR. Performance Requirements for Federal Purchases For the most up-to-date efficiency levels required by ENERGY STAR, look for

142

Using Variable Resolution Meshes to Model Tropical Cyclones in the Community Atmosphere Model  

Science Conference Proceedings (OSTI)

A statically-nested, variable-mesh option has recently been introduced into the Community Atmosphere Model’s (CAM) Spectral Element (SE) dynamical core that has become the default in CAM version 5.3. This paper presents a series of tests of ...

Colin M. Zarzycki; Christiane Jablonowski; Mark A. Taylor

143

Helium dilution refrigeration system  

DOE Patents (OSTI)

A helium dilution refrigeration system operable over a limited time period, and recyclable for a next period of operation is disclosed. The refrigeration system is compact with a self-contained pumping system and heaters for operation of the system. A mixing chamber contains [sup 3]He and [sup 4]He liquids which are precooled by a coupled container containing [sup 3]He liquid, enabling the phase separation of a [sup 3]He rich liquid phase from a dilute [sup 3]He-[sup 4]He liquid phase which leads to the final stage of a dilution cooling process for obtaining low temperatures. The mixing chamber and a still are coupled by a fluid line and are maintained at substantially the same level with the still cross sectional area being smaller than that of the mixing chamber. This configuration provides maximum cooling power and efficiency by the cooling period ending when the [sup 3]He liquid is depleted from the mixing chamber with the mixing chamber nearly empty of liquid helium, thus avoiding unnecessary and inefficient cooling of a large amount of the dilute [sup 3]He-[sup 4]He liquid phase. 2 figs.

Roach, P.R.; Gray, K.E.

1988-09-13T23:59:59.000Z

144

Modeling and Model Validation for Variable Generation Technologies: Focus on Wind Generation  

Science Conference Proceedings (OSTI)

The influx of variable-generation technologies, particularly wind generation, into the bulk transmission grid has been tremendous over the past decade. This trend will likely continue, in light of national and state renewable portfolio standards. Thus, there is a need for generic, standard, and publicly available models for variable-generation technologies for power system planning studies. The Electric Power Research Institute (EPRI), in collaboration with the Western Electricity Coordinating Council (...

2010-12-14T23:59:59.000Z

145

Extreme solid state refrigeration using nanostructured Bi-Te alloys.  

SciTech Connect

Materials are desperately needed for cryogenic solid state refrigeration. We have investigated nanostructured Bi-Te alloys for their potential use in Ettingshausen refrigeration to liquid nitrogen temperatures. These alloys form alternating layers of Bi{sub 2} and Bi{sub 2}Te{sub 3} blocks in equilibrium. The composition Bi{sub 4}Te{sub 3} was identified as having the greatest potential for having a high Ettingshausen figure of merit. Both single crystal and polycrystalline forms of this material were synthesized. After evaluating the Ettingshausen figure of merit for a large, high quality polycrystal, we simulated the limits of practical refrigeration in this material from 200 to 77 K using a simple device model. The band structure was also computed and compared to experiments. We discuss the crystal growth, transport physics, and practical refrigeration potential of Bi-Te alloys.

Lima Sharma, Ana L. (San Jose State University, San Jose, CA); Spataru, Dan Catalin; Medlin, Douglas L.; Sharma, Peter Anand; Morales, Alfredo Martin

2009-09-01T23:59:59.000Z

146

Performance bound for quantum absorption refrigerators  

E-Print Network (OSTI)

An implementation of quantum absorption chillers with three qubits has been recently proposed, that is ideally able to reach the Carnot performance regime. Here we study the working efficiency of such self-contained refrigerators, adopting a consistent treatment of dissipation effects. We demonstrate that the coefficient of performance at maximum cooling power is upper bounded by 3/4 of the Carnot performance. The result is independent of the details of the system and the equilibrium temperatures of the external baths. We provide design prescriptions that saturate the bound in the limit of a large difference between the operating temperatures. Our study suggests that delocalized dissipation, which must be taken into account for a proper modelling of the machine-baths interaction, is a fundamental source of irreversibility which prevents the refrigerator from approaching the Carnot performance arbitrarily closely in practice. The potential role of quantum correlations in the operation of these machines is also investigated.

Luis A. Correa; José P. Palao; Gerardo Adesso; Daniel Alonso

2012-12-18T23:59:59.000Z

147

Modes of Interannual Variability of the Southern Hemisphere Circulation Simulated by the CSIRO Climate Model  

Science Conference Proceedings (OSTI)

This study examines the capability of the Commonwealth Scientific and Industrial Research Organisation (CSIRO) climate model in simulating the observed modes of interannual variability of the Southern Hemisphere circulation. Modes of variability ...

Wenju Cai; Ian G. Watterson

2002-05-01T23:59:59.000Z

148

Systematic Biases in the Microphysics and Thermodynamics of Numerical Models That Ignore Subgrid-Scale Variability  

Science Conference Proceedings (OSTI)

A grid box in a numerical model that ignores subgrid variability has biases in certain microphysical and thermodynamic quantities relative to the values that would be obtained if subgrid-scale variability were taken into account. The biases are ...

Vincent E. Larson; Robert Wood; Paul R. Field; Jean-Christophe Golaz; Thomas H. Vonder Haar; William R. Cotton

2001-05-01T23:59:59.000Z

149

Cryogenic refrigeration apparatus  

DOE Patents (OSTI)

A technique for producing a cold environment in a refrigerant system in which input fluid from a compressor at a first temperature is introduced into an input channel of the system and is pre-cooled to a second temperature for supply to one of at least two stages of the system, and to a third temperature for supply to another stage thereof. The temperatures at such stages are reduced to fourth and fifth temperatures below the second and third temperatures, respectively. Fluid at the fourth temperature from the one stage is returned through the input channel to the compressor and fluid at the fifth temperature from the other stage is returned to the compressor through an output channel so that pre-cooling of the input fluid to the one stage occurs by regenerative cooling and counterflow cooling and pre-cooling of the input fluid to the other stage occurs primarily by counterflow cooling.

Crunkleton, James A. (Cambridge, MA)

1992-01-01T23:59:59.000Z

150

Cryogenic refrigeration apparatus  

DOE Patents (OSTI)

A technique for producing a cold environment in a refrigerant system in which input fluid from a compressor at a first temperature is introduced into an input channel of the system and is pre-cooled to a second temperature for supply to one of at least two stages of the system, and to a third temperature for supply to another stage thereof. The temperatures at such stages are reduced to fourth and fifth temperatures below the second and third temperatures, respectively. Fluid at the fourth temperature from the one stage is returned through the input channel to the compressor and fluid at the fifth temperature from the other stage is returned to the compressor through an output channel so that pre-cooling of the input fluid to the one stage occurs by regenerative cooling and counterflow cooling and pre-cooling of the input fluid to the other stage occurs primarily by counterflow cooling. 6 figs.

Crunkleton, J.A.

1992-03-31T23:59:59.000Z

151

The Proof is in the Pudding: How Refrigerator Standards Have Saved  

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

The Proof is in the Pudding: How Refrigerator Standards Have Saved The Proof is in the Pudding: How Refrigerator Standards Have Saved Consumers $Billions The Proof is in the Pudding: How Refrigerator Standards Have Saved Consumers $Billions July 11, 2011 - 12:33pm Addthis Today’s refrigerators have been designed to save energy and money without detriment to capacity, functionality, or extra features. | Image source: Building Technologies Program Today's refrigerators have been designed to save energy and money without detriment to capacity, functionality, or extra features. | Image source: Building Technologies Program Roland Risser Roland Risser Program Director, Building Technologies Office What does this mean for me? Today's refrigerators use only about 25 percent of the energy compared to models built in 1975. They've also increased in size by almost 20 percent, with lots of

152

The Proof is in the Pudding: How Refrigerator Standards Have Saved  

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

The Proof is in the Pudding: How Refrigerator Standards Have Saved The Proof is in the Pudding: How Refrigerator Standards Have Saved Consumers $Billions The Proof is in the Pudding: How Refrigerator Standards Have Saved Consumers $Billions July 11, 2011 - 12:33pm Addthis Today’s refrigerators have been designed to save energy and money without detriment to capacity, functionality, or extra features. | Image source: Building Technologies Program Today's refrigerators have been designed to save energy and money without detriment to capacity, functionality, or extra features. | Image source: Building Technologies Program Roland Risser Roland Risser Program Director, Building Technologies Office What does this mean for me? Today's refrigerators use only about 25 percent of the energy compared to models built in 1975. They've also increased in size by almost 20 percent, with lots of

153

Magnetic refrigeration apparatus and method  

SciTech Connect

The disclosure relates to refrigeration through magnetizing and demagnitizing a body by rotating it within a magnetic field. Internal and external heat exchange fluids and in one embodiment, a regenerator, are used.

Barclay, John A. (Los Alamos, NM); Overton, Jr., William C. (Los Alamos, NM); Stewart, Walter F. (Los Alamos, NM)

1984-01-01T23:59:59.000Z

154

Convective Precipitation Variability as a Tool for General Circulation Model Analysis  

Science Conference Proceedings (OSTI)

Precipitation variability is analyzed in two versions of the Community Atmospheric Model (CAM), the standard model, CAM, and a “multiscale modeling framework” (MMF), in which the cumulus parameterization has been replaced with a cloud-resolving ...

Charlotte A. DeMott; David A. Randall; Marat Khairoutdinov

2007-01-01T23:59:59.000Z

155

Do General Circulation Models Underestimate the Natural Variability in the Arctic Climate?  

Science Conference Proceedings (OSTI)

The authors examine the natural variability of the arctic climate system simulated by two very different models: the Geophysical Fluid Dynamics Laboratory (GFDL) global climate model, and an area-averaged model of the arctic atmosphere–sea ice–...

D. S. Battisti; C. M. Bitz; R. E. Moritz

1997-08-01T23:59:59.000Z

156

Spatial Variability and Interpolation of Stochastic Weather Simulation Model Parameters  

Science Conference Proceedings (OSTI)

The spatial variability of 58 precipitation and temperature parameters from the “generation of weather elements for multiple applications” (GEM) weather generator has been investigated over a region of significant complexity in topography and ...

Gregory L. Johnson; Christopher Daly; George H. Taylor; Clayton L. Hanson

2000-06-01T23:59:59.000Z

157

Biennial Variability in an Atmospheric General Circulation Model  

Science Conference Proceedings (OSTI)

Recent observational analyses have indicated that tropospheric quasi-biennial oscillations (QBs) may play a fundamental role in regulating the timing and strength of El Niño and the Southern Oscillation. The biennial variability is examined in ...

Michael A. Alexander; Klaus M. Weickmann

1995-03-01T23:59:59.000Z

158

DOE Closes Investigation into Energy Efficiency of Viking Refrigerator |  

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

Closes Investigation into Energy Efficiency of Viking Closes Investigation into Energy Efficiency of Viking Refrigerator DOE Closes Investigation into Energy Efficiency of Viking Refrigerator November 9, 2010 - 7:30pm Addthis The Department of Energy has closed its investigation into the energy efficiency of Viking Range Corporation's refrigerator-freezer model VCSB542. The Department initiated this investigation in response to allegations that the model failed to meet federal energy efficiency standards. After reviewing data provided by Viking for this model, the Department issued a testing demand on June 16, 2010 and initially tested four units, one of which was defective and replaced by a fifth unit. The test results showed that two Viking units failed the federal energy standard for maximum energy use, while two passed. Because of the wide variation in the

159

DOE Closes Investigation into Energy Efficiency of Viking Refrigerator |  

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

into Energy Efficiency of Viking into Energy Efficiency of Viking Refrigerator DOE Closes Investigation into Energy Efficiency of Viking Refrigerator November 9, 2010 - 7:30pm Addthis The Department of Energy has closed its investigation into the energy efficiency of Viking Range Corporation's refrigerator-freezer model VCSB542. The Department initiated this investigation in response to allegations that the model failed to meet federal energy efficiency standards. After reviewing data provided by Viking for this model, the Department issued a testing demand on June 16, 2010 and initially tested four units, one of which was defective and replaced by a fifth unit. The test results showed that two Viking units failed the federal energy standard for maximum energy use, while two passed. Because of the wide variation in the

160

Well simulation using Refrigerant 114  

DOE Green Energy (OSTI)

A simple method for the investigation of thermodynamic (substance) similarity in the two-phase domain is introduced based on the assumptions of a simplified model fluid. According to this method, the investigation of the conditions for thermodynamic similarity between substances in the two-phase region reveals the important role the latent heat of evaporation (h/sub fg/) plays in the definition of the property scales. These greatly influence the dynamic and geometric similarity of the process under investigation. The introduction of the thermodynamic similarity property scales into the energy conservation equations for a certain process (e.g., flow up a geothermal well) brings forth a thermodynamic length scale and kinetic energy scale. Refrigerant 114 has been examined for similarity with water substance according to this method and found to be adequate for geothermal well simulation in the laboratory. Low pressures and temperatures and a substantial reduction of mass flow rates and geometric scales are a few of the advantages of using R114 for such experiments.

Nikitopoulos, D.E.; Dickinson, D.A.; DiPippo, R.; Maeder, P.F.

1984-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Speed Control in Industrial Refrigeration: Theory, Application & Case Studies  

E-Print Network (OSTI)

It is often standard practice in the field of industrial refrigeration to design and operate systems with little regard toward part-load performance. This approach is understandable, whether viewed from the standpoint of the design engineer, plant manager or chief operator. As long a space temperature and production rates are maintained during peak periods, the refrigeration system is viewed as operating "correctly". The truth is, most refrigeration systems spend some, if not most operating hours at reduced capacity. Screw compressors back off slide valves, evaporator coils utilize back-pressure regulators (BPRs) or liquid solenoids, and condensers cycle fans. Unfortunately, these control methods do not provide the maximum attainable reduction in brake horsepower (BHP) as refrigeration capacity is reduced. This paper will discuss the application of variable speed drive (VSD, also called "variable frequency drive", "adjustable speed drive", "inverter", or simply "freq. drive") technology to capacity control of screw compressors, evaporator fans, and condenser fans. As shown through theory and case study, speed control of these components provides maximum flexibility, control and energy efficiency.

Wilcox, M. H.

1995-04-01T23:59:59.000Z

162

Thermal Analysis of Refrigeration Systems Used for Vaccine ...  

Science Conference Proceedings (OSTI)

Page 1. Thermal Analysis of Refrigeration Systems Used for Vaccine Storage ... Suitability of commercial refrigerators for vaccine storage not ...

2012-08-03T23:59:59.000Z

163

COMPUTER DESIGN AND OPTIMIZATION OF CRYOGENIC REFRIGERATION SYSTEMS  

E-Print Network (OSTI)

One Stage Compressor Heat Exchanger Refrigeration Load XBLOne Stage Compressor Heat Exchanger Refrigeration Load XBLcondensers, surface heat exchangers, surface condensers,

green, M.A.

2011-01-01T23:59:59.000Z

164

Superinsulation in refrigerators and freezers  

SciTech Connect

The results presented here were obtained during Phase 4 of the first CRADA, which had the specific objective of determining the lifetime of superinsulations when installed in simulated refrigerator doors. The second CRADA was established to evaluate and test design concepts proposed to significantly reduce energy consumption in a refrigerator-freezer that is representative of approximately 60% of the US market. The stated goal of this CRADA is to demonstrate advanced technologies which reduce, by 50%, the 1993 National Appliance Energy Conservation Act (NAECA) standard energy consumption for a 20 ft{sup 3} (570 L) top-mount, automatic-defrost, refrigerator-freezer. For a unit this size, the goal translates to an energy consumption of 1.003 kWh/d. The general objective of the research is to facilitate the introduction of efficient appliances by demonstrating design changes that can be effectively incorporated into new products. In previous work on this project, a Phase 1 prototype refrigerator-freezer achieved an energy consumption of 1.413 kWh/d [Vineyard, et al., 1995]. Following discussions with an advisory group comprised of all the major refrigerator-freezer manufacturers, several options were considered for the Phase 2 effort, one of which was cabinet heat load reductions.

Vineyard, E.; Stovall, T.K.; Wilkes, K.E.; Childs, K.W.

1998-02-01T23:59:59.000Z

165

A Simple Model of Stratospheric Dynamics Including Solar Variability  

Science Conference Proceedings (OSTI)

A simple dynamic model, truncated from the stratospheric wave–zonal flow interaction Holton and Mass model, is introduced and studied. This model consists of three ordinary differential equations controlled by two parameters: the initial ...

Alexander Ruzmaikin; John Lawrence; Cristina Cadavid

2003-05-01T23:59:59.000Z

166

Analysis and Modeling of the Natural Variability of Climate  

Science Conference Proceedings (OSTI)

After removing annual variability, power spectral analyses of local atmospheric temperature from hundreds of stations and ice core records have been carried out from timescales of 1 day to 200 kyr. A clear sequence of power-law behaviors is found ...

Jon D. Pelletier

1997-06-01T23:59:59.000Z

167

The Global Monsoon Variability Simulated by CMIP3 Coupled Climate Models  

Science Conference Proceedings (OSTI)

The global monsoon climate variability during the second half of the twentieth century simulated by 21 coupled global climate models (CGCMs) that participated in the World Climate Research Programme’s Coupled Model Intercomparison Project phase 3 ...

Hyung-Jin Kim; Bin Wang; Qinghua Ding

2008-10-01T23:59:59.000Z

168

North Atlantic Interannual Variability in a Coupled Ocean–Atmosphere Model  

Science Conference Proceedings (OSTI)

The primary mode of sea surface temperature variability in the North Atlantic on interannual timescales during winter is examined in a coupled ocean–atmosphere model. The model, developed at die Geophysical Fluid Dynamics Laboratory, is global in ...

Thomas L. Delworth

1996-10-01T23:59:59.000Z

169

Modeled winter sea ice variability and the North Atlantic Oscillation: a multi-century perspective  

E-Print Network (OSTI)

leading mode in a coupled sea ice-ocen model. J Clim 16:009-0550-7 Modeled winter sea ice variability and the Northrelationship between winter sea ice vari- ability and the

Strong, Courtenay; Magnusdottir, Gudrun

2010-01-01T23:59:59.000Z

170

Historical analysis of legal opinions with a sparse mixed-effects latent variable model  

Science Conference Proceedings (OSTI)

We propose a latent variable model to enhance historical analysis of large corpora. This work extends prior work in topic modelling by incorporating metadata, and the interactions between the components in metadata, in a general way. To test this, we ...

William Yang Wang; Elijah Mayfield; Suresh Naidu; Jeremiah Dittmar

2012-07-01T23:59:59.000Z

171

Data Assimilation as Synchronization of Truth and Model: Experiments with the Three-Variable Lorenz System  

Science Conference Proceedings (OSTI)

The potential use of chaos synchronization techniques in data assimilation for numerical weather prediction models is explored by coupling a Lorenz three-variable system that represents “truth” to another that represents “the model.” By adding ...

Shu-Chih Yang; Debra Baker; Hong Li; Katy Cordes; Morgan Huff; Geetika Nagpal; Ena Okereke; Josue Villafañe; Eugenia Kalnay; Gregory S. Duane

2006-09-01T23:59:59.000Z

172

Variability in a Nonlinear Model of the Atmosphere with Zonally Symmetric Forcing  

Science Conference Proceedings (OSTI)

The variability in a two-level nonlinear atmospheric model is examined. The model domain is spherical. The sole forcing is a zonally symmetric parameterization of the December-February insulation. An extended 1500 day run is carefully analyzed.

Harry H. Hendon; Dennis L. Hartmann

1985-12-01T23:59:59.000Z

173

Variability of Upper Pacific Ocean Overturning in a Coupled Climate Model  

Science Conference Proceedings (OSTI)

Variability of subtropical cell (STC) overturning in the upper Pacific Ocean is examined in a coupled climate model in light of large observed changes in STC transport. In a 1000-yr control run, modeled STC variations are smaller than observed, ...

William J. Merryfield; George J. Boer

2005-03-01T23:59:59.000Z

174

Interdecadal Variability in a Hybrid Coupled Ocean–Atmosphere–Sea Ice Model  

Science Conference Proceedings (OSTI)

Interdecadal climate variability in an idealized coupled ocean–atmosphere–sea-ice model is studied. The ocean component is a fully three-dimensional primitive equation model and the atmospheric component is a two-dimensional (2D) energy balance ...

S. Kravtsov; M. Ghil

2004-07-01T23:59:59.000Z

175

International Refrigeration: Order (2012-CE-1510)  

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

DOE ordered International Refrigeration Products to pay an $8,000 civil penalty after finding International Refrigeration had failed to certify that certain room air conditioners comply with the applicable energy conservation standard.

176

Thermoelectric refrigerator having improved temperature stabilization means  

DOE Patents (OSTI)

A control system for thermoelectric refrigerators is disclosed. The thermoelectric refrigerator includes at least one thermoelectric element that undergoes a first order change at a predetermined critical temperature. The element functions as a thermoelectric refrigerator element above the critical temperature, but discontinuously ceases to function as a thermoelectric refrigerator element below the critical temperature. One example of such an arrangement includes thermoelectric refrigerator elements which are superconductors. The transition temperature of one of the superconductor elements is selected as the temperature control point of the refrigerator. When the refrigerator attempts to cool below the point, the metals become superconductors losing their ability to perform as a thermoelectric refrigerator. An extremely accurate, first-order control is realized.

Falco, Charles M. (Woodridge, IL)

1982-01-01T23:59:59.000Z

177

DOE Proposes Higher Efficiency Standards for Refrigerators  

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

New Proposed Standards for Residential Refrigerators and Freezers to Lower Energy Use by as much as Twenty-Five Percent

178

Magnetocaloric Effect and Enhanced Refrigeration effectiveness in ...  

Science Conference Proceedings (OSTI)

Presentation Title, Magnetocaloric Effect and Enhanced Refrigeration effectiveness in ... Industrial Needs and Applications for Soft Magnetic Materials · Industrial ...

179

Optimization of the Refrigerant Capacity in Multiphase ...  

Science Conference Proceedings (OSTI)

Symposium, Magnetic Materials for Energy Applications. Presentation Title, Optimization of the Refrigerant Capacity in Multiphase Magnetocaloric Materials.

180

Ternary Dy-Er-Al magnetic refrigerants  

DOE Patents (OSTI)

A ternary magnetic refrigerant material comprising (Dy{sub 1{minus}x}Er{sub x})Al{sub 2} for a magnetic refrigerator using the Joule-Brayton thermodynamic cycle spanning a temperature range from about 60K to about 10K, which can be adjusted by changing the Dy to Er ratio of the refrigerant. 29 figs.

Gschneidner, K.A. Jr.; Takeya, Hiroyuki

1995-07-25T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Frontiers in thermoacoustic refrigeration and mixture separation  

E-Print Network (OSTI)

pulse-tube refrigerator shown in Figure 1 dissipates acoustic power by design because power must flowFrontiers in thermoacoustic refrigeration and mixture separation S. Backhaus1 , D. Geller2 , B oscillating thermodynamics in a gas in a sealed system. Since then, many related engines and refrigerators

182

Method and apparatus for desuperheating refrigerant  

DOE Patents (OSTI)

The present invention is an apparatus and method for de-superheating a primary refrigerant leaving a compressor wherein a secondary refrigerant is used between the primary refrigerant to be de-superheated. Reject heat is advantageously used for heat reclaim.

Zess, James A. (Kelso, WA); Drost, M. Kevin (Richland, WA); Call, Charles J. (Richland, WA)

1997-01-01T23:59:59.000Z

183

Ternary Dy-Er-Al magnetic refrigerants  

DOE Patents (OSTI)

A ternary magnetic refrigerant material comprising (Dy.sub.1-x Er.sub.x)Al.sub.2 for a magnetic refrigerator using the Joule-Brayton thermodynamic cycle spanning a temperature range from about 60K to about 10K, which can be adjusted by changing the Dy to Er ratio of the refrigerant.

Gschneidner, Jr., Karl A. (Ames, IA); Takeya, Hiroyuki (Ibaraki, JP)

1995-07-25T23:59:59.000Z

184

Bayesian Modeling of Population Variability -- Practical Guidance and Pitfalls  

SciTech Connect

With the advent of easy-to-use open-source software for Markov chain Monte Carlo (MCMC) simulation, hierarchical Bayesian analysis is gaining in popularity. This paper presents practical guidance for hierarchical Bayes analysis of typical problems in probabilistic safety assessment (PSA). The guidance is related to choosing parameterizations that accelerate convergence of the MCMC sampling and to illustrating the potential sensitivity of the results to the functional form chosen for the first-stage prior. This latter issue has significant ramifications because the mean of the average population variability curve (PVC) from hierarchical Bayes (or the mean of the point estimate distribution from empirical Bayes) can be very sensitive to this choice in cases where variability is large. Numerical examples are provided to illustrate the issues discussed.

Dana L. Kelly; Corwin L. Atwood

2008-05-01T23:59:59.000Z

185

Dilution Refrigeration of Multi-Ton Cold Masses  

E-Print Network (OSTI)

Dilution refrigeration is the only means to provide continuous cooling at temperatures below 250 mK. Future experiments featuring multi-ton cold masses require a new generation of dilution refrigeration systems, capable of providing a heat sink below 10 mK at cooling powers which exceed the performance of present systems considerably. This thesis presents some advances towards dilution refrigeration of multi-ton masses in this temperature range. A new method using numerical simulation to predict the cooling power of a dilution refrigerator of a given design has been developed in the framework of this thesis project. This method does not only allow to take into account the differences between an actual and an ideal continuous heat exchanger, but also to quantify the impact of an additional heat load on an intermediate section of the dilute stream. In addition, transient behavior can be simulated. The numerical model has been experimentally verified with a dilution refrigeration system which has been designed, ...

Wikus, P; CERN. Geneva

2007-01-01T23:59:59.000Z

186

Wheel-type magnetic refrigerator  

DOE Patents (OSTI)

The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load.

Barclay, John A. (Los Alamos, NM)

1983-01-01T23:59:59.000Z

187

Wheel-type magnetic refrigerator  

DOE Patents (OSTI)

The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load.

Barclay, J.A.

1982-01-20T23:59:59.000Z

188

Wheel-type magnetic refrigerator  

DOE Patents (OSTI)

The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load. 7 figs.

Barclay, J.A.

1983-10-11T23:59:59.000Z

189

Investigation of Chlorine-Free Refrigerants for Low-Temperature Supermarket Refrigeration  

Science Conference Proceedings (OSTI)

With the phaseout of chlorofluorocarbon (CFC) refrigerants, supermarkets are seeking a replacement for R-502, the refrigerant of choice for low-temperature (frozen food) refrigeration. EPRI has conducted field testing to characterize the performance of the new hydrofluorocarbon (HFC) nonchlorinated refrigerants replacements for R-502. Results showed that energy and demand savings can be obtained using these alternative refrigerants with zero ozone-depleting potential.

1996-08-10T23:59:59.000Z

190

Variability of the Thermohaline Circulation in an Ocean General Circulation Model Coupled to an Atmospheric Energy Balance Model  

Science Conference Proceedings (OSTI)

The variability of the ocean’s thermohaline circulation in an oceanic general circulation model (OGCM) coupled to a two-dimensional atmospheric energy balance model (EBM) is examined. The EBM calculates air temperatures by balancing heat fluxes, ...

David W. Pierce; K-Y. Kim; Tim P. Barnett

1996-05-01T23:59:59.000Z

191

Examining Uncertainty in Demand Response Baseline Models and Variability in Automated Response to Dynamic Pricing  

Science Conference Proceedings (OSTI)

Controlling electric loads to deliver power system services presents a number of interesting challenges. For example, changes in electricity consumption of Commercial and Industrial (C&I) facilities are usually estimated using counterfactual baseline models, and model uncertainty makes it difficult to precisely quantify control responsiveness. Moreover, C&I facilities exhibit variability in their response. This paper seeks to understand baseline model error and demand-side variability in responses to open-loop control signals (i.e. dynamic prices). Using a regression-based baseline model, we define several Demand Response (DR) parameters, which characterize changes in electricity use on DR days, and then present a method for computing the error associated with DR parameter estimates. In addition to analyzing the magnitude of DR parameter error, we develop a metric to determine how much observed DR parameter variability is attributable to real event-to-event variability versus simply baseline model error. Using data from 38 C&I facilities that participated in an automated DR program in California, we find that DR parameter errors are large. For most facilities, observed DR parameter variability is likely explained by baseline model error, not real DR parameter variability; however, a number of facilities exhibit real DR parameter variability. In some cases, the aggregate population of C&I facilities exhibits real DR parameter variability, resulting in implications for the system operator with respect to both resource planning and system stability.

Mathieu, Johanna L.; Callaway, Duncan S.; Kiliccote, Sila

2011-08-15T23:59:59.000Z

192

Object oriented modelling of variable envelope properties in buildings  

Science Conference Proceedings (OSTI)

The paper deals with some important aspects of continuous systems modelling approaches. Namely the traditional approach is based on block oriented schemes in which causal relations play an important role. However this causality is artificially generated ... Keywords: acausal modelling, intelligent building, object oriented modelling, simulation, thermal flows

Borut Zupan?i?; Anton Sodja

2008-12-01T23:59:59.000Z

193

Spray generators for absorption refrigeration systems  

DOE Patents (OSTI)

A spray generator for an absorption refrigeration system that includes a heat exchanger comprised of a multiplicity of variably spaced heat exchange tubes. The tubes are spaced close together near the top of the heat exchanger and spaced more widely apart near the bottom of the heat exchanger. Dilute absorbent solution is sprayed down through the heat exchanger. The close nesting of the tubes in the top portion of the heat exchanger retards liquid flow and aids heating of the solution. The wide spacing of the tubes in the lower section of the heat exchanger facilitate vapor flow out of the heat exchanger and eliminates liquid "blow-off". The top tubes are covered by a baffle to prevent the liquid solution from splashing out of the heat exchanger off of these top tubes.

Sibley, Howard W. (Baldwinsville, NY)

1979-06-19T23:59:59.000Z

194

Designing Environmentally Safe Refrigerants Using Mathematical Programming  

E-Print Network (OSTI)

Computer aided molecular design is a strategy in which a set of structural groups are systematically combined to form molecules with desired properties. In this paper, a mathematical programming based approach to computer aided molecular design is presented. Using a set of structural groups, the problem is formulated as a mixed integer nonlinear program in which discrete variables represent the number of each type of structural groups present in the candidate compound. The augmentedpenalty /outer-approximation algorithm is used to solve the MINLP to obtain compound(s) with an optimum value of an appropriate performance index such that molecular structural constraints, physical property constraints and process design limitations are met. With the current renewed interest in the environment, the suggested approach is applied to refrigerant design with an environmental constraint. The results indicate the viability of this approach. INTRODUCTION The chemical industry is constantly explo...

Amit P. Duvedi; Luke E. K. Achenie; Copyright Amit Duvedi; Luke Achenie

1996-01-01T23:59:59.000Z

195

Measurement and Modeling of Solar and PV Output Variability: Preprint  

DOE Green Energy (OSTI)

This paper seeks to understand what temporal and spatial scales of variability in global horizontal radiation are important to a PV plants and what measurements are needed to be able to characterize them. As solar radiation measuring instruments are point receivers it is important to understand how those measurements translate to energy received over a larger spatial extent. Also of importance is the temporal natural of variability over large spatial areas. In this research we use high temporal and spatial resolution measurements from multiple sensors at a site in Hawaii to create solar radiation fields at various spatial and temporal scales. Five interpolation schemes were considered and the high resolution solar fields were converted to power production for a PV power plant. It was found that the interpolation schemes are robust and create ramp distributions close to what would be computed if the average solar radiation field was used. We also investigated the possibility of using time averaged solar data from 1 sensor to recreate the ramp distribution from the 17 sensors. It was found that the ramping distribution from using appropriately time averaged data from 1 sensor can reasonably match the distribution created using the 17 sensor network.

Sengupta, M.

2011-04-01T23:59:59.000Z

196

Measurement and Modeling of Solar and PV Output Variability  

Science Conference Proceedings (OSTI)

This paper seeks to understand what temporal and spatial scales of variability in global horizontal radiation are important to a PV plants and what measurements are needed to be able to characterize them. As solar radiation measuring instruments are point receivers it is important to understand how those measurements translate to energy received over a larger spatial extent. Also of importance is the temporal natural of variability over large spatial areas. In this research we use high temporal and spatial resolution measurements from multiple sensors at a site in Hawaii to create solar radiation fields at various spatial and temporal scales. Five interpolation schemes were considered and the high resolution solar fields were converted to power production for a PV power plant. It was found that the interpolation schemes are robust and create ramp distributions close to what would be computed if the average solar radiation field was used. We also investigated the possibility of using time averaged solar data from 1 sensor to recreate the ramp distribution from the 17 sensors. It was found that the ramping distribution from using appropriately time averaged data from 1 sensor can reasonably match the distribution created using the 17 sensor network.

Sengupta, M.

2011-01-01T23:59:59.000Z

197

Low-temperature magnetic refrigerator  

SciTech Connect

The disclosure is directed to a low temperature 4 to 20 K. refrigeration apparatus and method utilizing a ring of magnetic material moving through a magnetic field. Heat exchange is accomplished in and out of the magnetic field to appropriately utilize the device to execute Carnot and Stirling cycles.

Barclay, John A. (Los Alamos, NM)

1985-01-01T23:59:59.000Z

198

Bayesian Analysis of Errors-in-Variables Growth Curve Models  

E-Print Network (OSTI)

Mixture Models. In Robust Bayesian Analysis. Lecture NotesA. (2004). Nonparametric Bayesian Data Analysis. Statistical95-110. West, M. (1990). Bayesian Kernel Density Estimation.

Huang, Hung-Jen

2010-01-01T23:59:59.000Z

199

Direct condensation refrigerant recovery and restoration system  

Science Conference Proceedings (OSTI)

This patent describes a refrigerant recovery and purification system for removing gaseous refrigerant from a disabled refrigeration unit, cleaning the refrigerant of contaminants, and converting the gaseous refrigerant to a liquid state for storage. It comprises a low pressure inlet section; a high pressure storage section; the low pressure inlet section comprising: an oil and refrigerant gas separator, including a separated oil removal means, first conduit means for connecting an inlet of the separator to the disabled refrigerant unit, a slack-sided accumulator, second conduit means connecting the separator to the slack-sided accumulator, a reclaim condenser, third conduit means connecting the separator and the reclaim condenser in series, an evaporator coil in the reclaim condenser connectable to a conventional operating refrigeration system for receiving a liquid refrigerant under pressure for expansion therein, the evaporator coil forming a condensing surface for condensing the refrigerant gas at near atmospheric pressure in the condenser, a liquid receiver, a reclaimed refrigerant storage tank, fourth conduit means further connecting the liquid receiver in series with the reclaim condenser, downstream thereof, means between the reclaim condenser and the liquid receiver.

Grant, D.C.H.

1992-03-10T23:59:59.000Z

200

FINAL PROJECT REPORT LOAD MODELING TRANSMISSION RESEARCH  

E-Print Network (OSTI)

appliances including lighting, refrigerators, dishwashers, clothes washers, dryers, fans, and electronic equipment for developing model databases

Lesieutre, Bernard

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Circumpolar Deep Water Circulation and Variability in a Coupled Climate Model  

Science Conference Proceedings (OSTI)

The natural variability of Circumpolar Deep Water (CDW) is analyzed using a long-term integration of a coupled climate model. The variability is decomposed using a standard EOF analysis into three separate modes accounting for 68% and 82% of the ...

Agus Santoso; Matthew H. England; Anthony C. Hirst

2006-08-01T23:59:59.000Z

202

Modelling and simulation of an autonomous variable speed micro hydropower station  

Science Conference Proceedings (OSTI)

In this paper, the modelling of an autonomous variable speed micro hydropower station is presented. It is composed of a doubly fed induction generator linked mechanically and electrically to a permanent magnet synchronous machine which may recover or ... Keywords: Distributed generation, Doubly fed induction machine, Micro hydroelectricity, Variable speed autonomous hydrogenerator

A. Ansel; B. Robyns

2006-06-01T23:59:59.000Z

203

Modelling and simulation of an autonomous variable speed micro hydropower station  

Science Conference Proceedings (OSTI)

In this paper, the modelling of an autonomous variable speed micro hydropower station is presented. It is composed of a doubly fed induction generator linked mechanically and electrically to a permanent magnet synchronous machine which may recover or ... Keywords: distributed generation, doubly fed induction machine, micro hydroelectricity, variable speed autonomous hydrogenerator

A. Ansel; B. Robyns

2006-06-01T23:59:59.000Z

204

A Representation of Variable Root Distribution in Dynamic Vegetation Models  

Science Conference Proceedings (OSTI)

Root distribution is treated as a static component in most current dynamic vegetation models (DVMs). While changes in leaf and stem biomass are reflected in leaf area index (LAI) and vegetation height via specific leaf area (SLA) and allometric ...

Vivek K. Arora; George J. Boer

2003-06-01T23:59:59.000Z

205

A Linear Model of Wintertime Low-Frequency Variability. Part I: Formulation and Forecast Skill  

Science Conference Proceedings (OSTI)

A linear inverse model (LIM) suitable for studies of atmospheric extratropical variability on longer than weekly timescales is constructed using observations of the past 30 years. Notably, it includes tropical diabatic heating as an evolving ...

Christopher R. Winkler; Matthew Newman; Prashant D. Sardeshmukh

2001-12-01T23:59:59.000Z

206

Interdecadal Variability of the Thermohaline Circulation in Box-Ocean Models Forced by Fixed Surface Fluxes  

Science Conference Proceedings (OSTI)

Intrinsic modes of decadal variability are analyzed using box-geometry ocean models forced by constant surface fluxes. An extensive parameter sensitivity analysis of the oscillatory behavior is carried out with respect to the spherical/Cartesian ...

Thierry Huck; Alain Colin de Verdière; Andrew J. Weaver

1999-05-01T23:59:59.000Z

207

Dynamic Cost-Loss Ratio Decision-making Model with an Autocorrelated Climate Variable  

Science Conference Proceedings (OSTI)

A dynamic decision-making problem is considered involving the use of information about the autocorrelation of a climate variable. Specifically, an infinite horizon, discounted version of the dynamic cost-loss ratio model is treated, in which only ...

Richard W. Katz

1993-01-01T23:59:59.000Z

208

Land Surface Hydrology Parameterization for Atmospheric General Circulation models Including Subgrid Scale Spatial Variability  

Science Conference Proceedings (OSTI)

Parameterizations are developed for the representation of subgrid hydrologic processes in atmospheric general circulation models. Reasonable a priori probability density functions of the spatial variability of soil moisture and of precipitation ...

D. Entekhabi; P. S. Eagleson

1989-08-01T23:59:59.000Z

209

Investigating the Mechanisms of Diurnal Rainfall Variability Using a Regional Climate Model  

Science Conference Proceedings (OSTI)

This study investigates the ability of a regional climate model (RCM) to simulate the diurnal cycle of precipitation over southeast Australia, to provide a basis for understanding the mechanisms that drive diurnal variability. When compared with ...

Jason P. Evans; Seth Westra

2012-10-01T23:59:59.000Z

210

Coupled Variability and Predictability in a Stochastic Climate Model of the Tropical Atlantic  

Science Conference Proceedings (OSTI)

The coupled variability and predictability of the tropical Atlantic ocean–atmosphere system were analyzed within the framework of a linear stochastic climate model. Despite the existence of a meridional dipole as the leading mode, tropical ...

Faming Wang; Ping Chang

2008-12-01T23:59:59.000Z

211

Empirical Mode Reduction in a Model of Extratropical Low-Frequency Variability  

Science Conference Proceedings (OSTI)

This paper constructs and analyzes a reduced nonlinear stochastic model of extratropical low-frequency variability. To do so, it applies multilevel quadratic regression to the output of a long simulation of a global baroclinic, quasigeostrophic, ...

D. Kondrashov; S. Kravtsov; M. Ghil

2006-07-01T23:59:59.000Z

212

Dynamical Origin of Low-Frequency Variability in a Highly Nonlinear Midlatitude Coupled Model  

Science Conference Proceedings (OSTI)

A novel mechanism of decadal midlatitude coupled variability, which crucially depends on the nonlinear dynamics of both the atmosphere and the ocean, is presented. The coupled model studied involves quasigeostrophic atmospheric and oceanic ...

S. Kravtsov; P. Berloff; W. K. Dewar; M. Ghil; J. C. McWilliams

2006-12-01T23:59:59.000Z

213

Multi-Scale Kernel Latent Variable Models for Nonlinear Time Series Pattern Matching  

Science Conference Proceedings (OSTI)

In this paper we propose a method for nonlinear time series pattern matching: "Multi-Scale Kernel Latent Variable (MSKLV) models". The pattern matching methodology includes multi-scale analysis using wavelet decomposition of time series and finding latent ...

B. Venkataramana Kini; C. Chandra Sekhar

2008-01-01T23:59:59.000Z

214

Modeling the Biosphere–Atmosphere System: The Impact of the Subgrid Variability in Rainfall Interception  

Science Conference Proceedings (OSTI)

Subgrid variability in rainfall distribution has been widely recognized as an important factor to include in the representation of land surface hydrology within climate models. In this paper, using West Africa as a case study, the impact of the ...

Guiling Wang; Elfatih A. B. Eltahir

2000-08-01T23:59:59.000Z

215

Using CMAQ for Exposure Modeling and Characterizing the Subgrid Variability for Exposure Estimates  

Science Conference Proceedings (OSTI)

Atmospheric processes and the associated transport and dispersion of atmospheric pollutants are known to be highly variable in time and space. Current air-quality models that characterize atmospheric chemistry effects, for example, the Community ...

Vlad Isakov; John S. Irwin; Jason Ching

2007-09-01T23:59:59.000Z

216

Analysis of Intraseasonal and Interannual Variability of the Asian Summer Monsoon Using a Hidden Markov Model  

Science Conference Proceedings (OSTI)

Intraseasonal and interannual variability of Asian summer monsoon rainfall in pentad precipitation data is examined using a hidden Markov model (HMM). The spatial patterns of discrete rainfall states derived with the HMM and the associated ...

Jin Ho Yoo; Andrew W. Robertson; In-Sik Kang

2010-10-01T23:59:59.000Z

217

Indian Ocean Dipolelike Variability in the CSIRO Mark 3 Coupled Climate Model  

Science Conference Proceedings (OSTI)

Coupled ocean–atmosphere variability in the tropical Indian Ocean is explored with a multicentury integration of the Commonwealth Scientific and Industrial Research Organisation (CSIRO) Mark 3 climate model, which runs without flux adjustment. ...

Wenju Cai; Harry H. Hendon; Gary Meyers

2005-05-01T23:59:59.000Z

218

North Pacific Decadal Variability and Climate Change in the IPCC AR4 Models  

Science Conference Proceedings (OSTI)

The two leading modes of North Pacific sea surface temperature (SST) and sea level pressure (SLP), as well as their connections to tropical variability, are explored in the 24 coupled climate models used in the Intergovernmental Panel on Climate ...

Jason C. Furtado; Emanuele Di Lorenzo; Niklas Schneider; Nicholas A. Bond

2011-06-01T23:59:59.000Z

219

Surface Energy Fluxes and Coupled Variability in the Tropics of a Coupled General Circulation Model  

Science Conference Proceedings (OSTI)

The effect of wind-evaporative feedbacks upon ENSO, and the coupling of Pacific and Indian Ocean variability, is considered based upon a 110-yr simulation from a coupled ocean and atmosphere general circulation model.

R. L. Miller; X. Jiang

1996-07-01T23:59:59.000Z

220

Exploratory Long-Range Models to Estimate Summer Climate Variability over Southern Africa  

Science Conference Proceedings (OSTI)

Teleconnection predictors are explored using multivariate regression models in an effort to estimate southern African summer rainfall and climate impacts one season in advance. The preliminary statistical formulations include many variables ...

Mark R. Jury; Henry M. Mulenga; Simon J. Mason

1999-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

ENSO and Pacific Decadal Variability in the Community Climate System Model Version 4  

Science Conference Proceedings (OSTI)

This study presents an overview of the El Niño–Southern Oscillation (ENSO) phenomenon and Pacific decadal variability (PDV) simulated in a multicentury preindustrial control integration of the NCAR Community Climate System Model version 4 (CCSM4) ...

Clara Deser; Adam S. Phillips; Robert A. Tomas; Yuko M. Okumura; Michael A. Alexander; Antonietta Capotondi; James D. Scott; Young-Oh Kwon; Masamichi Ohba

2012-04-01T23:59:59.000Z

222

A Simple Parameterization of Cloud Water Related Variables for Use in Boundary Layer Models  

Science Conference Proceedings (OSTI)

A simple parameterization of cloud water related variables has been developed which can be used in meteorological models that use a prognostic equation for the turbulent kinetic energy. Based on the results of large-eddy simulations (LES), ...

J. W. M. Cuijpers; P. Bechtold

1995-07-01T23:59:59.000Z

223

Extractive SPL adoption using multi-level variability modeling  

Science Conference Proceedings (OSTI)

Software Product Line engineering aims at reusing and automating software development to reduce costs, have shorter development cycles, and maintain quality. However, for organizations with settled development processes and a large code base, adopting ... Keywords: model-driven engineering, software product lines

Carlos Parra; Leonardo Giral; Alvaro Infante; Camilo Cortés

2012-09-01T23:59:59.000Z

224

Fuzzy Inductive Reasoning for Variable Selection Analysis and Modeling of Biological Systems  

E-Print Network (OSTI)

Fuzzy Inductive Reasoning (FIR) is a qualitative inductive modeling and simulation methodology for dealing with dynamical systems. It has proven to be a powerful tool for qualitative model identification and prediction of future behavior of various kinds of dynamical systems, especially from the soft sciences, such as biology, biomedicine, and ecology. This paper focuses on modeling aspects of the FIR methodology. It is shown that the FIR variable selection analysis is a useful tool not only for FIR but also for other classical quantitative methodologies such as NARMAX (Nonlinear AutoRegressive Moving Average modeling with eXternal inputs). The tool allows to obtain models that interpret a system under study in optimal ways, in the sense that these models are well suited for predicting the future behavior of the system they represent. The FIR variable selection analysis turns out to work well even in those applications where standard statistical variable selection analysis does not pro...

Angela Nebot; Francois E. Cellier; Ra' ul Carvajal V

1997-01-01T23:59:59.000Z

225

New empirical correlations for sizing adiabatic capillary tubes in refrigeration systems  

Science Conference Proceedings (OSTI)

This paper presents new empirical correlations that have been developed for sizing adiabatic capillary tubes used in small vapor compression refrigeration and air-conditioning systems. A numerical model which is based on the basic equations of conservation of mass

S. Shodiya; A. A. Aahar; N. Henry; A. N. Darus

2012-01-01T23:59:59.000Z

226

Evaluating energy dissipation during expansion in a refrigeration cycle using flue pipe acoustic resonators  

E-Print Network (OSTI)

This research evaluates the feasibility of using a flue pipe acoustic resonator to dissipate energy from a refrigerant stream in order to achieve greater cooling power from a cryorefrigeration cycle. Two models of the ...

Luckyanova, Maria N. (Maria Nickolayevna)

2008-01-01T23:59:59.000Z

227

North Atlantic modeling of low-frequency variability in mode water formation  

E-Print Network (OSTI)

The generation of interannual and near-decadal variability in the formation of mode waters in the western North Atlantic is investigated in the realistic framework of an isopycnic coordinate ocean model forced with atmospheric data from 1946 to 1988. At Bermuda, the model reproduces quite well the observed potential vorticity and isopycnal depth anomalies associated with the subtropical mode water (STMW). Heat storage and preconditioning of the convective activity are found to be the important factors for the generation of STMW variability, with persistence of cold (warm) conditions, associated with anomalous heat loss (gain) over the western subtropics, being more significant for the generation of the simulated variability than are strong anomalous events in isolated years. In the Labrador Sea, the model captures the phase and order of magnitude of the observed near-decadal variability in the convective activity, if not its maximum amplitude. The simulated potential vorticity anomali...

Afonso M. Paiva; Eric P. Chassignet

2001-01-01T23:59:59.000Z

228

Optimal Performance of Quantum Refrigerators  

E-Print Network (OSTI)

A reciprocating quantum refrigerator is studied with the purpose of determining the limitations of cooling to absolute zero. We find that if the energy spectrum of the working medium possesses an uncontrollable gap, then there is a minimum achievable temperature above zero. Such a gap, combined with a negligible amount of noise, prevents adiabatic following during the demagnetization stage which is the necessary condition for reaching $T_c \\to 0$. The refrigerator is based on an Otto cycle where the working medium is an interacting spin system with an energy gap. For this system the external control Hamiltonian does not commute with the internal interaction. As a result during the demagnetization and magnetization segments of the operating cycle the system cannot follow adiabatically the temporal change in the energy levels. We connect the nonadiabatic dynamics to quantum friction. An adiabatic measure is defined characterizing the rate of change of the Hamiltonian. Closed form solutions are found for a const...

Feldmann, Tova

2009-01-01T23:59:59.000Z

229

A compact rotating dilution refrigerator  

E-Print Network (OSTI)

We describe the design and performance of a new rotating dilution refrigerator that will primarily be used for investigating the dynamics of quantized vortices in superfluid 4He. All equipment required to operate the refrigerator and perform experimental measurements is mounted on two synchronously driven, but mechanically decoupled, rotating carousels. The design allows for relative simplicity of operation and maintenance and occupies a minimal amount of space in the laboratory. Only two connections between the laboratory and rotating frames are required for the transmission of electrical power and helium gas recovery. Measurements on the stability of rotation show that rotation is smooth to around 0.001 rad/s up to angular velocities in excess of 2.5 rad/s. The behavior of a high-Q mechanical resonator during rapid changes in rotation has also been investigated.

Fear, M J; Chorlton, D A; Zmeev, D E; Gillott, S J; Sellers, M C; Richardson, P P; Agrawal, H; Batey, G; Golov, A I

2013-01-01T23:59:59.000Z

230

Quantum-enhanced absorption refrigerators  

E-Print Network (OSTI)

Thermodynamics is a branch of science blessed by an unparalleled combination of generality of scope and formal simplicity. Based on few natural assumptions together with the four laws, it sets the boundaries between possible and impossible in macroscopic aggregates of matter. This triggered groundbreaking achievements in physics, chemistry and engineering over the last two centuries. Close analogues of those fundamental laws are now being established at the level of individual quantum systems, thus placing limits on the operation of quantum-mechanical devices. Here we study quantum absorption refrigerators, which are driven by heat rather than external work. We establish thermodynamic performance bounds for these machines and investigate their quantum origin. We also show how those bounds may be pushed beyond what is classically achievable, by suitably tailoring the environmental fluctuations via quantum reservoir engineering techniques. Such superefficient quantum-enhanced cooling realises a promising step towards the technological exploitation of autonomous quantum refrigerators.

Luis A. Correa; José P. Palao; Daniel Alonso; Gerardo Adesso

2013-08-19T23:59:59.000Z

231

Suction muffler for refrigeration compressor  

SciTech Connect

A hermetic refrigeration compressor includes a suction muffler formed from two pieces of plastic material mounted on the cylinder housing. One piece is cylindrical in shape with an end wall having an aperture for receiving a suction tube connected to the cylinder head. The other piece fits over and covers the other end of the cylindrical piece, and includes a flaring entrance horn which extends toward the return line on the sidewall of the compressor shell.

Nelson, Richard T. (Worthington, OH); Middleton, Marc G. (West Jefferson, OH)

1983-01-01T23:59:59.000Z

232

Suction muffler for refrigeration compressor  

DOE Patents (OSTI)

A hermetic refrigeration compressor includes a suction muffler formed from two pieces of plastic material mounted on the cylinder housing. One piece is cylindrical in shape with an end wall having an aperture for receiving a suction tube connected to the cylinder head. The other piece fits over and covers the other end of the cylindrical piece, and includes a flaring entrance horn which extends toward the return line on the sidewall of the compressor shell. 5 figs.

Nelson, R.T.; Middleton, M.G.

1983-01-25T23:59:59.000Z

233

Compatibility of refrigerants and lubricants with elastomers  

SciTech Connect

Information contained in this reporters designed to assist the air-conditioning and refrigeration industry in the selection of suitable elastomeric gasket and seal materials that will prove useful in various refrigerant and refrigeration lubricant environments. Swell measurements have been made on approximately 50% of the proposed elastomers (94 total)in both the lubricant (7 total) and refrigerant (10 total) materials. Swell behavior in the these fluids have been determined using weight and in situ diameter measurements for the refrigerants and weight, diameter and thickness measurements for the lubricants. Weight and diameter measurements are repeated after 2 hours and 24 hours for samples removed from the refrigerant test fluids and 24 hours after removal from the lubricants.

Hamed, G.R.; Seiple, R.H.

1992-07-01T23:59:59.000Z

234

Transport Refrigeration Units: A Technical Assessment  

Science Conference Proceedings (OSTI)

This report evaluates the prospects for operating transport refrigeration systems on electricity while they are stationary at a distribution center or refrigerated warehouses. Because most transport refrigeration units (TRUs) in use today are powered by diesel engines, concentrations of diesel exhaust products including particulate matter occur near these distribution centers. Operating TRUs on electricity would eliminate diesel exhaust emissions concentrations at these facilities, but would increase cos...

2004-09-29T23:59:59.000Z

235

List of Refrigerators Incentives | Open Energy Information  

Open Energy Info (EERE)

Refrigerators Incentives Refrigerators Incentives Jump to: navigation, search The following contains the list of 657 Refrigerators Incentives. CSV (rows 1-500) CSV (rows 501-657) Incentive Incentive Type Place Applicable Sector Eligible Technologies Active AEP Ohio - Commercial Custom Project Rebate Program (Ohio) Utility Rebate Program Ohio Commercial Fed. Government Industrial Institutional Local Government Nonprofit Schools State Government Tribal Government Boilers Central Air conditioners Chillers Custom/Others pending approval Furnaces Heat pumps Heat recovery Lighting Lighting Controls/Sensors Processing and Manufacturing Equipment Refrigerators Yes AEP Ohio - Commercial Energy Efficiency Rebate Program (Ohio) Utility Rebate Program Ohio Commercial Fed. Government Industrial

236

Building Technologies Office: Refrigerated Beverage Vending Machines...  

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

Energy Use to Save Money. Learn More. News DOE Issues Notice of Proposed Rulemaking for Commercial Refrigeration Equipment Energy Conservation Standard August 29, 2013 DOE Issues...

237

Regenerator for Magnetic Refrigerants - Energy Innovation Portal  

Magnetic refrigeration is being investigated as an alternative to conventional gas compressor technology ... because of its potential to save energy and ...

238

An Alternative Refrigeration System For Automotive Applications.  

E-Print Network (OSTI)

??The air conditioning systems currently utilized in automobiles are the vapor compression systems. This type of system has many disadvantages: the refrigerant used is not… (more)

McLaughlin, Shannon

2005-01-01T23:59:59.000Z

239

Multi-stage Cascaded Stirling Refrigerator  

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

have developed a multi-stage refrigerator, designed to recapture and utilize the acoustic energy that would ordinarily be wasted in traditional Stirling configurations. Available...

240

NIST Quantum Refrigerator Offers Extreme Cooling and ...  

Science Conference Proceedings (OSTI)

... NIST's prototype solid-state refrigerator uses quantum physics in the square chip mounted on the green circuit board to cool the much larger copper ...

2013-03-05T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Magnetic Refrigeration a 21 - Programmaster.org  

Science Conference Proceedings (OSTI)

Presentation Title, Magnetic Refrigeration a 21st Century Highly Efficient and Green ... Alloy Design and Powder Processing of Mn-Al Based Materials for Rare

242

Optimal Sequencing of Central Refrigeration Equipment in an Industrial Plant  

E-Print Network (OSTI)

A model was developed to find a viable solution to the problem of selecting the optimal sequence of refrigeration equipment (chillers, cooling towers, pumps) to operate in a Central Utility Plant. The optimal equipment sequence is that sequence which has the lowest energy cost to operate at a given plant cooling load and outside air wet bulb temperature. and satisfies all the constraints associated with the refrigeration system. Selection of the optimal equipment sequence is very difficult given the complexity of the refrigeration system and the dynamic nature of the plant cooling load. As a solution a computer program was developed to generate optimal equipment sequences to operate for combinations of a wide range of plant cooling loads and outside air wet bulb temperatures. Analysis of the solution identified the need for a retrofit project to remove "vital" constraints in order to improve the refrigeration system's performance. The solution to the problem was then incorporated in the operating procedures for the Central Utility Plant.

Fiorino, D. P.; Priest, J. W.

1986-01-01T23:59:59.000Z

243

Long-Term Variability in a Coupled Atmosphere–Biosphere Model  

Science Conference Proceedings (OSTI)

A fully coupled atmosphere–biosphere model, version 3 of the NCAR Community Climate Model (CCM3) and the Integrated Biosphere Simulator (IBIS), is used to illustrate how vegetation dynamics may be capable of producing long-term variability in the ...

Christine Delire; Jonathan A. Foley; Starley Thompson

2004-10-01T23:59:59.000Z

244

Federal Energy Management Program: Covered Product Category: Refrigerated  

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

Refrigerated Beverage Vending Machines to someone by E-mail Refrigerated Beverage Vending Machines to someone by E-mail Share Federal Energy Management Program: Covered Product Category: Refrigerated Beverage Vending Machines on Facebook Tweet about Federal Energy Management Program: Covered Product Category: Refrigerated Beverage Vending Machines on Twitter Bookmark Federal Energy Management Program: Covered Product Category: Refrigerated Beverage Vending Machines on Google Bookmark Federal Energy Management Program: Covered Product Category: Refrigerated Beverage Vending Machines on Delicious Rank Federal Energy Management Program: Covered Product Category: Refrigerated Beverage Vending Machines on Digg Find More places to share Federal Energy Management Program: Covered Product Category: Refrigerated Beverage Vending Machines on AddThis.com...

245

DOE Testing Reveals Samsung Refrigerator Does Not Meet Energy...  

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

Testing Reveals Samsung Refrigerator Does Not Meet Energy Star Requirements DOE Testing Reveals Samsung Refrigerator Does Not Meet Energy Star Requirements March 16, 2010 - 4:28pm...

246

Air-Conditioning, Heating, and Refrigeration Institute (AHRI...  

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

Conditioning, Heating, and Refrigeration Institute (AHRI) Regulatory Burden RFI Air-Conditioning, Heating, and Refrigeration Institute (AHRI) Regulatory Burden RFI These comments...

247

U.S. Residential Miscellaneous Refrigeration Products: Results...  

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

Residential Miscellaneous Refrigeration Products: Results from Amazon Mechanical Turk Surveys Title U.S. Residential Miscellaneous Refrigeration Products: Results from Amazon...

248

COMPUTER DESIGN AND OPTIMIZATION OF CRYOGENIC REFRIGERATION SYSTEMS  

E-Print Network (OSTI)

be used to design and optimize refrigeration cycles as wellCOMPUTER DESIGN AND OPTIMIZATION OF CRYOGENIC REFRIGERATIONTrial Design Fixed state parameters (bar) Refrigeration

green, M.A.

2011-01-01T23:59:59.000Z

249

China Refrigerator Information Label: Specification Development and Potential Impact  

E-Print Network (OSTI)

ERKELEY N ATIONAL L ABORATORY China Refrigerator InformationDivision Jianhong Cheng China National Institute of7 Table 2 Coefficient Values for China Refrigerator 2003

Fridley, David

2008-01-01T23:59:59.000Z

250

Applying Ecological Interface Design to Experimental Apparatus Used to Monitor a Refrigeration Plant.  

E-Print Network (OSTI)

A small refrigeration plant, for teaching refrigeration theory, used a control console built to traditional design guidelines: one output in the display for each sensor in the plant. This style of console is notorious for inducing high cognitive loads on operators and for displaying redundant data. Often the high cognitive load is the result of inconsistency between the intent for displaying the data and the format of the displayed data. An interface, based on Ecological Interface Design Theory (EID) was designed and implemented. The completed interface provided the operator with information commensurate with the operator's mental model derived from the system image. During testing of the new interface the expert operator's mental model of the refrigeration system was modified due to improved observation of the refrigeration plant's operational parameters. The application achieved the desired result and reduced the operator's workload by removing a cognitive task - determining system s...

Pat Lehane; Mark Toleman; John Benecke

2000-01-01T23:59:59.000Z

251

Recent variability of the solar spectral irradiance and its impact on climate modelling  

E-Print Network (OSTI)

The lack of long and reliable time series of solar spectral irradiance (SSI) measurements makes an accurate quantification of solar contributions to recent climate change difficult. Whereas earlier SSI observations and models provided a qualitatively consistent picture of the SSI variability, recent measurements by the SORCE satellite suggest a significantly stronger variability in the ultraviolet (UV) spectral range and changes in the visible and near-infrared (NIR) bands in anti-phase with the solar cycle. A number of recent chemistry-climate model (CCM) simulations have shown that this might have significant implications on the Earth's atmosphere. Motivated by these results, we summarize here our current knowledge of SSI variability and its impact on Earth's climate. We present a detailed overview of existing SSI measurements and provide thorough comparison of models available to date. SSI changes influence the Earth's atmosphere, both directly, through changes in shortwave (SW) heating and therefore, temp...

Ermolli, I; de Wit, T Dudok; Krivova, N A; Tourpali, K; Weber, M; Unruh, Y C; Gray, L; Langematz, U; Pilewskie, P; Rozanov, E; Schmutz, W; Shapiro, A; Solanki, S K; Woods, T N

2013-01-01T23:59:59.000Z

252

The Use of Water Vapor as a Refrigerant: Impact of Cycle Modifications on Commercial Viability  

SciTech Connect

This project investigated the economic viability of using water as the refrigerant in a 1000-ton chiller application. The most attractive water cycle configuration was found to be a flash-intercooled, two-stage cycle using centrifugal compressors and direct contact heat exchangers. Component level models were developed that could be used to predict the size and performance of the compressors and heat exchangers in this cycle as well as in a baseline, R-134a refrigeration cycle consistent with chillers in use today. A survey of several chiller manufacturers provided information that was used to validate and refine these component models. The component models were integrated into cycle models that were subsequently used to investigate the life-cycle costs of both an R-134a and water refrigeration cycle. It was found that the first cost associated with the water as a refrigerant cycle greatly exceeded the savings in operating costs associated with its somewhat higher COP. Therefore, the water refrigeration cycle is not an economically attractive option to today's R-134a refrigeration system. There are a number of other issues, most notably the requirements associated with purging non-condensable gases that accumulate in a direct contact heat exchanger, which will further reduce the economic viability of the water cycle.

Brandon F. Lachner, Jr.; Gregory F. Nellis; Douglas T. Reindl

2004-08-30T23:59:59.000Z

253

Cosmological Models of Universe with Variable Deceleration Parameter in Lyra's Manifold  

E-Print Network (OSTI)

FRW models of the universe have been studied in the cosmological theory based on Lyra's manifold. A new class of exact solutions has been obtained by considering a time dependent displacement field for variable deceleration parameter from which three models of the universe are derived (i) exponential (ii) polynomial and (iii) sinusoidal form respectively. The behaviour of these models of the universe are also discussed. Finally some possibilities of further problems and their investigations have been pointed out.

A. Pradhan; J. P. Shahi; C. B. Singh

2006-08-14T23:59:59.000Z

254

The Use of lce-Liquid Water Potential Temperature as a Thermodynamic Variable In Deep Atmospheric Models  

Science Conference Proceedings (OSTI)

Previous studies have shown liquid water potential temperature to be an inappropriate choice for a thermodynamic variable in a deep cumulus convection model. In this study, an alternate form of this variable called ice-liquid water potential ...

Gregory J. Tripoli; William R. Cotton

1981-05-01T23:59:59.000Z

255

Date | 1Refrigeration and Air Conditioning EMA Education and Training Date | 2Refrigeration and Air Conditioning EMA Education and Training  

E-Print Network (OSTI)

Date | 1Refrigeration and Air Conditioning EMA Education and Training #12;Date | 2Refrigeration Flow Coil Design etc. Finger Print Relationship Every evaporator is unique Unstable Region * = examples

Oak Ridge National Laboratory

256

Seven-effect absorption refrigeration  

DOE Patents (OSTI)

A seven-effect absorption refrigeration cycle is disclosed utilizing three absorption circuits. In addition, a heat exchanger is used for heating the generator of the low absorption circuit with heat rejected from the condenser and absorber of the medium absorption circuit. A heat exchanger is also provided for heating the generator of the medium absorption circuit with heat rejected from the condenser and absorber of the high absorption circuit. If desired, another heat exchanger can also be provided for heating the evaporator of the high absorption circuit with rejected heat from either the condenser or absorber of the low absorption circuit.

DeVault, Robert C. (Knoxville, TN); Biermann, Wendell J. (Fayetteville, NY)

1989-01-01T23:59:59.000Z

257

Seven-effect absorption refrigeration  

DOE Patents (OSTI)

A seven-effect absorption refrigeration cycle is disclosed utilizing three absorption circuits. In addition, a heat exchanger is used for heating the generator of the low absorption circuit with heat rejected from the condenser and absorber of the medium absorption circuit. A heat exchanger is also provided for heating the generator of the medium absorption circuit with heat rejected from the condenser and absorber of the high absorption circuit. If desired, another heat exchanger can also be provided for heating the evaporator of the high absorption circuit with rejected heat from either the condenser or absorber of the low absorption circuit. 1 fig.

DeVault, R.C.; Biermann, W.J.

1989-05-09T23:59:59.000Z

258

Design of Industrial Process Refrigeration Systems  

E-Print Network (OSTI)

When considering electric driven refrigeration compressors, proper integration with the process may result in reduced power consumption. However, the total utility situation must be considered when evaluating the compressor driver. Conversion from steam drivers to electric drivers may be more economical when considering proper process integration. These questions and various scenarios must be addressed in light of the total process requirements and constraints. During the last few years, Union Carbide has successfully applied ADVENT™ technology to several complex processes that utilize refrigeration systems. In most cases the design of a complex refrigeration system in isolation (i.e., without considering process integration) generally results in non-optimum refrigeration levels and excessive refrigeration consumption. By applying ADVENT™ Process Integration Technologv to these non-optimal designs, retrofit projects have emerged that clearly identify how to optimize the existing design with good project economics. This paper presents the results of an ADVENT Process Integration Study for the Electric Power Research Institute (EPRI) of Palo Alto, California. The study objective was to demonstrate process synthesis techniques for retrofit design in two industrial refrigeration intensive processes: an olefins process and a beer brewery process. Study results for each retrofit design are explained along with generalized guidelines for application to other processes. An industry scoping portion of the study is discussed in terms of identifying refrigeration intensive processes. Specific and general conclusions are presented to help facilitate proper industrial refrigeration system design throughout the industry.

Witherell, W. D.

1987-09-01T23:59:59.000Z

259

Compatibility of refrigerants and lubricants with elastomers  

Science Conference Proceedings (OSTI)

The information contained in this report is designed to assist the air-conditioning and refrigeration industry in the selection of suitable elastomeric gasket and seal materials that will prove useful in various refrigerant and refrigeration lubricant environments. 97% of the swell measurements have been made to date. The other 3% of the measurements are contingent on availability of additional R-32. Swell behavior in the fluids have been determined using weight and in situ diameter measurements for the refrigerants and weight, diameter and thickness measurements for the lubricants. Weight and diameter measurements are repeated after 2 and 24 hours for samples removed from the refrigerant test fluids and 24 hours after removal from the lubricants.

Hamed, G.R.; Seiple, R.H.

1993-01-01T23:59:59.000Z

260

Compatibility of refrigerants and lubricants with elastomers  

Science Conference Proceedings (OSTI)

Information contained in this report is designed to assist the air-conditioning and refrigeration industry in the selection of suitable elastomeric gasket and seal materials that will prove useful in various refrigerant and refrigeration lubricant environments. 97% of the swell measurements have been made to date. The other 3% of the measurements are contingent on the availability of additional quantities of R-32. Swell behavior in the fluids have been determined using weight and in situ diameter measurements for the refrigerants and weight, diameter and thickness measurements for the lubricants. Weight and diameter measurements are repeated after 2 hours and 24 hours for samples removed from the refrigerant test fluids and 24 hours after removal from the lubricants.

Hamed, G.R.; Seiple, R.H.

1992-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Optimal Performance of Quantum Refrigerators  

E-Print Network (OSTI)

A reciprocating quantum refrigerator is studied with the purpose of determining the limitations of cooling to absolute zero. We find that if the energy spectrum of the working medium possesses an uncontrollable gap, then there is a minimum achievable temperature above zero. Such a gap, combined with a negligible amount of noise, prevents adiabatic following during the demagnetization stage which is the necessary condition for reaching $T_c \\to 0$. The refrigerator is based on an Otto cycle where the working medium is an interacting spin system with an energy gap. For this system the external control Hamiltonian does not commute with the internal interaction. As a result during the demagnetization and magnetization segments of the operating cycle the system cannot follow adiabatically the temporal change in the energy levels. We connect the nonadiabatic dynamics to quantum friction. An adiabatic measure is defined characterizing the rate of change of the Hamiltonian. Closed form solutions are found for a constant adiabatic measure for all the cycle segments. We have identified a family of quantized frictionless cycles with increasing cycle times. These cycles minimize the entropy production. Such frictionless cycles are able to cool to $T_c=0$. External noise on the controls eliminates these frictionless cycles. The influence of phase and amplitude noise on the demagnetization and magnetization segments is explicitly derived. An extensive numerical study of optimal cooling cycles was carried out which showed that at sufficiently low temperature the noise always dominates restricting the minimum temperature.

Tova Feldmann; Ronnie Kosloff

2009-06-04T23:59:59.000Z

262

Oil cooled, hermetic refrigerant compressor  

DOE Patents (OSTI)

A hermetic refrigerant compressor having an electric motor and compressor assembly in a hermetic shell is cooled by oil which is first cooled in an external cooler and is then delivered through the shell to the top of the motor rotor where most of it is flung radially outwardly within the confined space provided by the cap which channels the flow of most of the oil around the top of the stator and then out to a multiplicity of holes to flow down to the sump and provide further cooling of the motor and compressor. Part of the oil descends internally of the motor to the annular chamber to provide oil cooling of the lower part of the motor, with this oil exiting through vent hole also to the sump. Suction gas with entrained oil and liquid refrigerant therein is delivered to an oil separator from which the suction gas passes by a confined path in pipe to the suction plenum and the separated oil drops from the separator to the sump. By providing the oil cooling of the parts, the suction gas is not used for cooling purposes and accordingly increase in superheat is substantially avoided in the passage of the suction gas through the shell to the suction plenum. 3 figs.

English, W.A.; Young, R.R.

1985-05-14T23:59:59.000Z

263

Oil cooled, hermetic refrigerant compressor  

DOE Patents (OSTI)

A hermetic refrigerant compressor having an electric motor and compressor assembly in a hermetic shell is cooled by oil which is first cooled in an external cooler 18 and is then delivered through the shell to the top of the motor rotor 24 where most of it is flung radially outwardly within the confined space provided by the cap 50 which channels the flow of most of the oil around the top of the stator 26 and then out to a multiplicity of holes 52 to flow down to the sump and provide further cooling of the motor and compressor. Part of the oil descends internally of the motor to the annular chamber 58 to provide oil cooling of the lower part of the motor, with this oil exiting through vent hole 62 also to the sump. Suction gas with entrained oil and liquid refrigerant therein is delivered to an oil separator 68 from which the suction gas passes by a confined path in pipe 66 to the suction plenum 64 and the separated oil drops from the separator to the sump. By providing the oil cooling of the parts, the suction gas is not used for cooling purposes and accordingly increase in superheat is substantially avoided in the passage of the suction gas through the shell to the suction plenum 64.

English, William A. (Murrysville, PA); Young, Robert R. (Murrysville, PA)

1985-01-01T23:59:59.000Z

264

Novel materials for laser refrigeration  

SciTech Connect

The status of optical refrigeration of rare-earth-doped solids is reviewed, and the various factors that limit the performance of current laser-cooling materials are discussed. Efficient optical refrigeration is possible in materials for which {Dirac_h}{omega}{sub max} < E{sub p}/8, where {Dirac_h}{omega}{sub max} is the maximum phonon energy of the host material and E{sub p} is the pump energy of the rare-earth dopant. Transition-metal and OH{sup -}impurities at levels >100 ppb are believed to be the main factors for the limited laser-cooling performance in current materials. The many components of doped ZBLAN glass pose particular processing challenges. Binary fluoride glasses such as YF{sub 3}-LiF are considered as alternatives to ZBLAN. The crystalline system KPb{sub 2}CI{sub 5} :Dy{sup 3+} is identified as a prime candidate for high-efficiency laser cooling.

Hehlen, Markus P [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

265

Modelling and Analysis of Variable Speed Wind Turbines with Induction Generator during Grid  

E-Print Network (OSTI)

Modelling and Analysis of Variable Speed Wind Turbines with Induction Generator during Grid Fault Wind Turbines with Induction Generator during Grid Fault by Sigrid M. Bolik Institute of Energy turbine technology has undergone rapid developments. Growth in size and the optimization of wind turbines

Hansen, René Rydhof

266

Interactive visualisation of products in online configurators: a case study for variability modelling technologies  

Science Conference Proceedings (OSTI)

Numerous companies develop interactive environments to assist users in customising sales products through the selection of configuration options. A visual representation of these products is an important factor in terms of user experience. However, an ... Keywords: configurator, software product line, user interface, variability modelling

Marianela Ciolfi Felice, Joao Bosco Ferreira Filho, Mathieu Acher, Arnaud Blouin, Olivier Barais

2013-08-01T23:59:59.000Z

267

Ocean Model Diagnosis of Low-Frequency Climate Variability in the South Atlantic Region  

Science Conference Proceedings (OSTI)

South Atlantic Ocean variability is investigated by means of an ocean general circulation model (ORCA2), forced with the NCEP–NCAR reanalyses for the 1948–99 period. A rotated EOF analysis of the mixed layer temperature suggests a breakdown of ...

Frank Colberg; C. J. C. Reason

2007-03-01T23:59:59.000Z

268

Ocean Model Diagnosis of Interannual Coevolving SST Variability in the South Indian and South Atlantic Oceans  

Science Conference Proceedings (OSTI)

A global ocean model (ORCA2) forced with 50 yr of NCEP–NCAR reanalysis winds and heat fluxes has been used to investigate the evolution and forcing of interannual dipolelike sea surface temperature (SST) variability in the South Indian and South ...

J. C. Hermes; C. J. C. Reason

2005-08-01T23:59:59.000Z

269

Wind-Driven Thermocline Variability in the Pacific: A Model–Data Comparison  

Science Conference Proceedings (OSTI)

The spatial and temporal patterns of interannual temperature variability within the main thermocline (200–400-m depth) of the Pacific (30°S–60°N) during 1968–97 are documented in two observational datasets and an ocean general circulation model ...

Jo Ann Lysne; Clara Deser

2002-04-01T23:59:59.000Z

270

Multiple Equilibria, Natural Variability, and Climate Transitions in an Idealized Ocean–Atmosphere Model  

Science Conference Proceedings (OSTI)

An idealized coupled ocean–atmosphere is constructed to study climatic equilibria and variability. The model focuses on the role of large-scale fluid motions in the climate system. The atmospheric component is an eddy-resolving two-level global ...

R. Saravanan; James C. Mc Williams

1995-10-01T23:59:59.000Z

271

Decadal Variability of the Kuroshio Extension: Observations and an Eddy-Resolving Model Hindcast  

Science Conference Proceedings (OSTI)

Low-frequency variability of the Kuroshio Extension (KE) is studied using observations and a multidecadal (1950–2003) hindcast by a high-resolution (0.1°), eddy-resolving, global ocean general circulation model for the Earth Simulator (OFES). In ...

Bunmei Taguchi; Shang-Ping Xie; Niklas Schneider; Masami Nonaka; Hideharu Sasaki; Yoshikazu Sasai

2007-06-01T23:59:59.000Z

272

Modeling and design of control system for variable speed wind turbine in all operating region  

Science Conference Proceedings (OSTI)

In order to get the maximum power from the wind, the variable-speed wind turbine should run at different speed when wind speed changes. In this paper a control system is introduced to get this purpose base on establishing the three-mass model of the ... Keywords: doubly-fed induction generator (DFIG), feed-forward compensator, loop-shaping, pitch controller, speed controller, three-mass model, wind turbine

Wu Dingguo; Wang Zhixin

2008-05-01T23:59:59.000Z

273

Refrigerant Phase-Change Stirling-Cycle Solar Power Towers  

Science Conference Proceedings (OSTI)

This paper firstly introduces the principles of Refrigerant Phase-Change Stirling-Cycle solar power towers This heat engines use solar reservoire. When the refrigerant in an engine cylinder absorbs heat from high-temperature heat sources, refrigerant ... Keywords: refrigerant phase-change cycle, heat engines, solar power tower, finite-time thermodynamics

Dezhong Huang

2011-01-01T23:59:59.000Z

274

Magnetic Refrigeration Technology for High Efficiency Air Conditioning  

SciTech Connect

Magnetic refrigeration was investigated as an efficient, environmentally friendly, flexible alternative to conventional residential vapor compression central air conditioning systems. Finite element analysis (FEA) models of advanced geometry active magnetic regenerator (AMR) beds were developed to minimize bed size and thus magnet mass by optimizing geometry for fluid flow and heat transfer and other losses. Conventional and magnetocaloric material (MCM) regenerator fabrication and assembly techniques were developed and advanced geometry passive regenerators were built and tested. A subscale engineering prototype (SEP) magnetic air conditioner was designed, constructed and tested. A model of the AMR cycle, combined with knowledge from passive regenerator experiments and FEA results, was used to design the regenerator beds. A 1.5 Tesla permanent magnet assembly was designed using FEA and the bed structure and plenum design was extensively optimized using FEA. The SEP is a flexible magnetic refrigeration platform, with individually instrumented beds and high flow rate and high frequency capability, although the current advanced regenerator geometry beds do not meet performance expectations, probably due to manufacturing and assembly tolerances. A model of the AMR cycle was used to optimize the design of a 3 ton capacity magnetic air conditioner, and the system design was iterated to minimize external parasitic losses such as heat exchanger pressure drop and fan power. The manufacturing cost for the entire air conditioning system was estimated, and while the estimated SEER efficiency is high, the magnetic air conditioning system is not cost competitive as currently configured. The 3 ton study results indicate that there are other applications where magnetic refrigeration is anticipated to have cost advantages over conventional systems, especially applications where magnetic refrigeration, through the use of its aqueous heat transfer fluid, could eliminate intermediate heat exchangers or oil distribution issues found in traditional vapor compression systems.

Boeder, A; Zimm, C

2006-09-30T23:59:59.000Z

275

Dual-circuit, multiple-effect refrigeration system and method  

DOE Patents (OSTI)

A dual circuit absorption refrigeration system comprising a high temperature single-effect refrigeration loop and a lower temperature double-effect refrigeration loop separate from one another and provided with a double-condenser coupling therebetween. The high temperature condenser of the single-effect refrigeration loop is double coupled to both of the generators in the double-effect refrigeration loop to improve internal heat recovery and a heat and mass transfer additive such as 2-ethyl-1-hexanol is used in the lower temperature double-effect refrigeration loop to improve the performance of the absorber in the double-effect refrigeration loop.

DeVault, Robert C. (Knoxville, TN)

1995-01-01T23:59:59.000Z

276

Modeling the Effect of Land Surface Evaporation Variability on Precipitation Variability. Part II: Time- and Space-Scale structure  

Science Conference Proceedings (OSTI)

This is the second of a two-part article investigating the impact of variations of land surface evaporability on the interannual variability of precipitation. The first goal of this part is to analyze the relationship between the atmospheric ...

Oreste Reale; Paul Dirmeyer; Adam Schlosser

2002-08-01T23:59:59.000Z

277

China Refrigerator Information Label: Specification Development and Potential Impact  

SciTech Connect

In the last five years, China's refrigerator market has grown rapidly, and now urban markets are showing signs of saturation, with ownership rates in urban households reaching 92%. Rural markets continue to grow from a much lower base. As a result of this growth, the Chinese government in 2006 decided to revise the refrigerator standards and its associated efficiency grades for the mandatory energy information label. In the Chinese standards process, the efficiency grades for the information label are tied to the minimum standards. Work on the minimum standards revision began in 2006 and continued through the first half of 2007, when the draft standard was completed under the direction of the China National Institute of Standardization (CNIS). Development of the information label grades required consideration of stakeholder input, continuity with the previous grade classification, ease of implementation, and potential impacts on the market. In this process, CLASP, with the support of METI/IEEJ, collaborated with CNIS to develop the efficiency grades, providing technical input to the process, comment and advice on particular technical issues, and evaluation of the results. After three months of effort and three drafts of the final grade specifications, this work was completed. In addition, in order to effectively evaluate the impact of the label on China's market, CLASP further provided assistance to CNIS to collect data on both the efficiency distribution and product volume distribution of refrigerators on the market. The new information label thresholds to be implemented in 2008 maintain the approach first adopted in 2005 of establishing efficiency levels relative to the minimum standard, but increased the related required efficiency levels by 20% over those established in 2003 and implemented in 2005. The focus of improvement was on the standard refrigerator/freezer (class 5), which constitutes the bulk of the Chinese market. Indeed, the new requirements to achieve grade 1 on the label are now virtually as stringent as those for US Energy Star-qualified or EU A-grade refrigerators. When the energy information label went into effect in March 2005, refrigerator manufacturers were required to display their declared level of efficiency on the label and report it to the China Energy Label Center (CELC), a newly established unit of CNIS responsible for label program management. Because of the visible nature of the label, it was found, through a METI/IEEJ-supported study, that MEPS non-compliance dropped from 4% to zero after the label became mandatory, and that the percentage of higher-grade refrigerators increased. This suggests that the label itself does have potential for shifting the market to higher-efficiency models (Lin 2007). One challenge, however, of assessing this potential impact is the lack of a comprehensive baseline of market efficiency and a program to evaluate the market impact on a yearly basis. As a result, the impact evaluation in this study draws upon the market transformation experience of the related EU energy information label, for which quantitative assessments of its market impact exist. By assuming a parallel process unfolding in China, it is possible to look at the potential impact of the label to 2020. The results of the analysis demonstrates that a robust market transformation program in China focused on the energy information label could save substantial amounts of electricity by 2020, totaling 16.4 TWh annually by that year, compared to a case in which the efficiency distribution of refrigerators was frozen at the 2007 level. Remarkably, the impact of a successful market transformation program with the label would essentially flatten the consumption of electricity for refrigerator use throughout most of the next decade, despite the expectations of continued growth in total stock by nearly 190 million units. At the end of this period, total consumption begins to rise again, as the least efficient of the units have been mostly removed from the market. Such a level of savings would reduce CO{sub

Fridley, David; Fridley, David; Zheng, Nina; Zhou, Nan; Aden, Nathaniel; Lin, Jiang; Jianhong, Cheng; Sakamoto, Tomoyuki

2008-02-01T23:59:59.000Z

278

Estimates of Refrigerator Loads in Public Housing Based on Metered Consumption Data  

SciTech Connect

The New York Power Authority (NYPA), the New York City Housing Authority (NYCHA), and the U.S. Departments of Housing and Urban Development (HUD) and Energy (DOE) have joined in a project to replace refrigerators in New York City public housing with new, highly energy-efficient models. This project laid the ground work for the Consortium for Energy Efficiency (CEE) and DOE to enable housing authorities throughout the United States to bulk-purchase energy-efficient appliances. DOE helped develop and plan the program through the ENERGY STAR@ Partnerships program conducted by its Pacific Nofiwest National Laboratory (PNNL). PNNL was subsequently asked to conduct the savings evahations for 1996 and 1997. PNNL designed the metering protocol and occupant survey, supplied and calibrated the metering equipment, and managed and analyzed the data. The 1996 metering study of refrigerator energy usage in New York City public housing (Pratt and Miller 1997) established the need and justification for a regression-model-based approach to an energy savings estimate. The need originated in logistical difficulties associated with sampling the population and pen?orming a stratified analysis. Commonly, refrigerators[a) with high representation in the popula- tion were missed in the sampling schedule, leaving significant holes in the sample and difficulties for the stratified anrdysis. The just{jfcation was found in the fact that strata (distinct groups of identical refrigerators) were not statistically distinct in terms of their label ratio (ratio of metered consumption to label rating). This finding suggested a general regression model could be used to represent the consumption of all refrigerators in the population. In 1996 a simple two-coefficient regression model, a function of only the refrigerator label rating, was developed and used to represent the existing population of refrigerators. A key concept used in the 1997 study grew from findings in a small number of apartments metered in 1996 with a detailed protocol. Fifteen-minute time-series data of ambient and compartment temperatures and refrigerator power were analyzed and demonstrated the potential for reducing power records into three components. This motivated the development of an analysis process to divide the metered consumption into baseline load, occupant-associated load, and defrosting load. The baseline load is the consumption that would occur if the refrigerator were on but had no occupant usage load (no door- opening events) and the defrosting mechanism was disabled. The motivation behind this component reduction process was the hope that components could be more effectively modeled than the total. We reasoned that the components would lead to abetter (more general and more significant) understanding of the relationships between consumption, the characteristics of the refrigerator, and its operating environment.

JD Miller; RG Pratt

1998-09-11T23:59:59.000Z

279

Phenomenological Varying Modified Chaplygin Gas with Variable $G$ and $?$: Toy Models for Our Universe  

E-Print Network (OSTI)

This article motivated by the recent articles and results of two authors. Recently, J. Sadeghi and H. Farahani presented a work [1], where they include viscosity and analyze general model, by this way they extended models considered by M. Khurshudyan [2] and [3]. In this article, We tempt to consider varying Modified Chaplygin gas model in case of variable $G$ and $\\Lambda$. It is well known, that varying $G$ and $\\Lambda$ gives rise to modified field equations and modified conservation laws. We will consider two different toy models. First model is a Universe with one component phenomenological gas of our consideration, while for the second model we assume existence of a composed fluid of gas and a matter with $P=\\omega(t)\\rho_{m}$. Sign changeable interaction between fluids is accepted. We will analyze important cosmological parameters like EoS parameter of a fluid, deceleration parameter $q$ of the model.

J. Sadeghi; M. Khurshudyan; H. Farahani

2013-08-08T23:59:59.000Z

280

Plate Fin Heat Exchanger Model with Axial Conduction and Variable Properties  

E-Print Network (OSTI)

Future superconducting radio frequency (SRF) cavities, as part of Project X at Fermilab, will be cooled to superfluid helium temperatures by a cryogenic distribution system supplying cold supercritical helium. To reduce vapor fraction during the final Joule-Thomson (J-T) expansion into the superfluid helium cooling bath, counter-flow, plate-fin heat exchangers will be utilized. Due to their compact size and ease of fabrication, plate-fin heat exchangers are an effective option. However, the design of compact and high-effectiveness cryogenic heat exchangers operating at liquid helium temperatures requires consideration of axial heat conduction along the direction of flow, in addition to variable fluid properties. Here we present a numerical model that includes the effects of axial conduction and variable properties for a plate fin heat exchanger. The model is used to guide design decisions on heat exchanger material choice and geometry. In addition, the J-T expansion process is modeled with the heat exchanger ...

Hansen, B J; Klebaner, A; 10.1063/1.4706971

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Bearing construction for refrigeration compresssor  

DOE Patents (OSTI)

A hermetic refrigeration compressor has a cylinder block and a crankshaft rotatable about a vertical axis to reciprocate a piston in a cylinder on the cylinder block. A separate bearing housing is secured to the central portion of the cylinder block and extends vertically along the crankshaft, where it carries a pair of roller bearings to journal the crankshaft. The crankshaft has a radially extending flange which is journaled by a thrust-type roller bearing above the bearing housing to absorb the vertical forces on the crankshaft so that all three of the roller bearings are between the crankshaft and the bearing housing to maintain and control the close tolerances required by such bearings.

Middleton, Marc G. (Wyoming, MI); Nelson, Richard T. (Worthington, OH)

1988-01-01T23:59:59.000Z

282

Optimization of Industrial Refrigeration Systems  

E-Print Network (OSTI)

A computer program designed to optimize the size of an evaporative condenser in a two-stage industrial refrigeration plant was created. The program sizes both the high-stage and low-stage compressors and an evaporative condenser. Once the initial system is sized, a year long plant simulation is performed resulting in electric energy consumption profile and an exergy destruction profile for each component and for the system. The program uses actual regional hourly outside dry bulb and wet bulb temperatures for both sizing and simulation. An exergoeconomic optimization uses the results of the simulation combined with component and energy costs to optimize the condenser size such that both plant costs and energy losses are minimized.

Flack, P. J.; Sharp, M. K.; Case, M. E.; Gregory, R. W.; Case, P. L.

1995-04-01T23:59:59.000Z

283

Status of not-in-kind refrigeration technologies for household space conditioning, water heating and food refrigeration  

Science Conference Proceedings (OSTI)

This paper presents a review of the next generation not-in-kind technologies to replace conventional vapor compression refrigeration technology for household applications. Such technologies are sought to provide energy savings or other environmental benefits for space conditioning, water heating and refrigeration for domestic use. These alternative technologies include: thermoacoustic refrigeration, thermoelectric refrigeration, thermotunneling, magnetic refrigeration, Stirling cycle refrigeration, pulse tube refrigeration, Malone cycle refrigeration, absorption refrigeration, adsorption refrigeration, and compressor driven metal hydride heat pumps. Furthermore, heat pump water heating and integrated heat pump systems are also discussed due to their significant energy saving potential for water heating and space conditioning in households. The paper provides a snapshot of the future R&D needs for each of the technologies along with the associated barriers. Both thermoelectric and magnetic technologies look relatively attractive due to recent developments in the materials and prototypes being manufactured.

Bansal, Pradeep [ORNL; Vineyard, Edward Allan [ORNL; Abdelaziz, Omar [ORNL

2012-01-01T23:59:59.000Z

284

Opportunities for Energy Efficiency and Automated Demand Response in Industrial Refrigerated Warehouses in California  

E-Print Network (OSTI)

D. Brown (2004). Industrial Refrigeration Best PracticesD. Brown (2004). Industrial Refrigeration Best Practicesoutlet – common in industrial refrigeration Source: Wilcox,

Lekov, Alex

2009-01-01T23:59:59.000Z

285

U.S. Residential Miscellaneous Refrigeration Products: Results from Amazon Mechanical Turk Surveys  

E-Print Network (OSTI)

refrigeration products use vapor compression technology toicemakers and non-vapor compression refrigerators and+4.5) million non-vapor compression refrigerators in U.S.

Greenblatt, Jeffery B.

2013-01-01T23:59:59.000Z

286

Small Commercial Refrigeration Incentive | Department of Energy  

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

Small Commercial Refrigeration Incentive Small Commercial Refrigeration Incentive Small Commercial Refrigeration Incentive < Back Eligibility Agricultural Commercial Industrial Institutional Nonprofit Savings Category Appliances & Electronics Commercial Lighting Lighting Maximum Rebate Incentives over $5,000 must be pre-approved Program Info Funding Source Efficiency Vermont Public Benefit Fund Expiration Date 06/30/2013 State Vermont Program Type State Rebate Program Rebate Amount Outside Air Economizers: $1,250 Evaporator Fan Motors: $20 - $100 Evaporator Fan Motor Controls: $550 Door/Frame Heater Controls: $50 per door Case Light Occupancy Controls: $40 LED Refrigerator and Freezer Case Light Fixtures: $6 - $15 per foot Energy Star Ice Machines: $50 - $75 Efficient Compressors: $200 Display Case Strip-Curtain and Continuous Covers: $6 per foot

287

Cospolich Refrigerator: Proposed Penalty (2013-CE-5314)  

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

DOE alleged in a Notice of Proposed Civil Penalty that Cospolich Refrigerator Co, Inc. failed to certify walk-in cooler or freezer components as compliant with the energy conservation standards.

288

Refrigerator Manufacturers: Proposed Penalty (2013-CE-5341)  

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

DOE alleged in a Notice of Proposed Civil Penalty that Refrigerator Manufacturers, LLC failed to certify a variety of walk-in cooler or freezer components as compliant with the applicable energy conservation standards.

289

Defrost Temperature Termination in Supermarket Refrigeration Systems  

SciTech Connect

The objective of this project was to determine the potential energy savings associated with implementing demand defrost strategies to defrost supermarket refrigerated display case evaporators, as compared to the widely accepted current practice of controlling display case defrost cycles with a preset timer. The defrost heater energy use of several representative display case types was evaluated. In addition, demand defrost strategies for refrigerated display cases as well as those used in residential refrigerator/freezers were evaluated. Furthermore, it is anticipated that future work will include identifying a preferred defrost strategy, with input from Retail Energy Alliance members. Based on this strategy, a demand defrost system will be designed which is suitable for supermarket refrigerated display cases. Limited field testing of the preferred defrost strategy will be performed in a supermarket environment.

Fricke, Brian A [ORNL; Sharma, Vishaldeep [ORNL

2011-11-01T23:59:59.000Z

290

Loveland Water & Power- Refrigerator Recycling Program  

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

Loveland Water & Power is providing an incentive for its customers to recycle their old refrigerators. Interested customers can call the utility to arrange a time to pick up the old...

291

Elastic Metal Alloy Refrigerants: Thermoelastic Cooling  

SciTech Connect

BEETIT Project: UMD is developing an energy-efficient cooling system that eliminates the need for synthetic refrigerants that harm the environment. More than 90% of the cooling and refrigeration systems in the U.S. today use vapor compression systems which rely on liquid to vapor phase transformation of synthetic refrigerants to absorb or release heat. Thermoelastic cooling systems, however, use a solid-state material—an elastic shape memory metal alloy—as a refrigerant and a solid to solid phase transformation to absorb or release heat. UMD is developing and testing shape memory alloys and a cooling device that alternately absorbs or creates heat in much the same way as a vapor compression system, but with significantly less energy and a smaller operational footprint.

2010-10-01T23:59:59.000Z

292

Working Fluids Low Global Warming Potential Refrigerants  

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

Working Fluids Low GWP Working Fluids Low GWP Refrigerants - CRADA Ed Vineyard Oak Ridge National Laboratory vineyardea@ornl.gov (865) 574-0576 3 April 2013 2 | Building Technologies Office eere.energy.gov Purpose & Objectives Problem Statement: - High GWP refrigerants increase CO 2 equivalent emissions for HVAC&R equipment - Low GWP alternatives may increase energy consumption, introduce safety risks, require significant modifications to equipment, and have higher costs

293

Combined cold compressor/ejector helium refrigerator  

DOE Patents (OSTI)

A refrigeration apparatus having an ejector operatively connected with a cold compressor to form a two-stage pumping system. This pumping system is used to lower the pressure, and thereby the temperature of a bath of boiling refrigerant (helium). The apparatus as thus arranged and operated has substantially improved operating efficiency when compared to other processes or arrangements for achieving a similar low pressure.

Brown, Donald P. (Southold, NY)

1985-01-01T23:59:59.000Z

294

Working Fluids Low Global Warming Potential Refrigerants  

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

Working Fluids Low GWP Working Fluids Low GWP Refrigerants - CRADA Ed Vineyard Oak Ridge National Laboratory vineyardea@ornl.gov (865) 574-0576 3 April 2013 2 | Building Technologies Office eere.energy.gov Purpose & Objectives Problem Statement: - High GWP refrigerants increase CO 2 equivalent emissions for HVAC&R equipment - Low GWP alternatives may increase energy consumption, introduce safety risks, require significant modifications to equipment, and have higher costs

295

ARI delegation to Japan on Alternative Refrigerants  

SciTech Connect

Researchers from ARI member companies spoke at the International Conference on Alternative Refrigerants in Tokyo and visited several Japanese organizations for the purpose of exchanging information on alternative refrigerants. The specific purpose of the meetings was to review the methods being utilized to screen alternatives to CFCs and HCFCs: materials compatibility screening methods, lubricant testing techniques, as well as flammability studies. A list of papers presented at the conference is included.

Not Available

1993-02-01T23:59:59.000Z

296

BNL Refrigerant Overview Presentation to the  

E-Print Network (OSTI)

0.25 4700 Cold boxes, environmental chambers R-718 Water 212 0 N/A Steam-driven absorption chiller 4750 Older centrifugal chillers (>200 tons) R-12 CFC -20 1 10900 Old refrigerators and vehicle A/C R-13/C mach. R-123 HCFC 81 1.3 77 Newer centrifugal chillers (>200 tons) R-134a HFC -15 0 1430 Refrigerators

Homes, Christopher C.

297

Combined cold compressor/ejector helium refrigerator  

DOE Patents (OSTI)

A refrigeration apparatus having an ejector operatively connected with a cold compressor to form a two-stage pumping system. This pumping system is used to lower the pressure, and thereby the temperature of a bath of boiling refrigerant (helium). The apparatus as thus arranged and operated has substantially improved operating efficiency when compared to other processes or arrangements for achieving a similar low pressure.

Brown, D.P.

1984-06-05T23:59:59.000Z

298

Predictability of Linear Coupled Systems. Part II: An Application to a Simple Model of Tropical Atlantic Variability  

Science Conference Proceedings (OSTI)

A predictability analysis developed within a general framework of linear stochastic dynamics in a companion paper is applied to a simple coupled climate model of tropical Atlantic variability (TAV). The simple model extends the univariate ...

Ping Chang; R. Saravanan; Faming Wang; Link Ji

2004-04-01T23:59:59.000Z

299

Simulation of the Tropical Pacific Climate with a Coupled Ocean-Atmosphere General Circulation Model. Part II: Interannual Variability  

Science Conference Proceedings (OSTI)

Two multiyear simulations with a coupled ocean-atmosphere general circulation model (GCM)-totaling 45 years-are used to investigate interannual variability at the equator. The model consists of the UCLA global atmospheric GCM coupled to the GFDL ...

A. W. Robertson; C-C. Ma; M. Ghil; C. R. Mechoso

1995-05-01T23:59:59.000Z

300

Stratospheric Variability in Twentieth-Century CMIP5 Simulations of the Met Office Climate Model: High Top versus Low Top  

Science Conference Proceedings (OSTI)

An examination is made of stratospheric climate, circulation, and variability in configurations of the Hadley Centre Global Environmental Model version 2 (HadGEM2) differing only in stratospheric resolution and the placement of the model lid. This ...

Scott M. Osprey; Lesley J. Gray; Steven C. Hardiman; Neal Butchart; Tim J. Hinton

2013-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Ground Loops for Heat Pumps and Refrigeration  

E-Print Network (OSTI)

Ground loops are used for water source heat pumps. Refrigeration can be put on a ground loop. Water-cooled condensing units are more efficient than air-cooled, and they can be put indoors. Indoor location makes piping for desuperheater hot water easy. Since refrigeration equipment runs more than heat pumps, energy savings can be large for ground-coupled refrigeration. The paper presents a design procedure for ground loops for heat pumps, hot water, ice machines, and water-cooled refrigeration. It gives an overview of the commercial ground-coupled systems in Louisiana that have both refrigeration and heat pumps. Systems vary from small offices to a three-story office building with 187 tons. A chain of hamburger outlets uses total ground-coupling in all of its stores. A grocery store has ground-coupling for heat pumps and refrigeration. Desuperheaters provide 80 percent of the hot water for a coin laundry in the same building. A comparison of energy costs in a bank with a ground-coupled heat pump system to a similar bank with air-conditioning and gas for heat revealed a 31 percent reduction in utility costs for the ground-coupled building. Two buildings of the Mississippi Power and Light Co. have ground-coupled heat pumps in one, and high efficiency air source heat pumps in the other. Energy savings in nine months was 60,000 kWh (25 percent), and electric peak demand was reduced 42 kW (35 percent).

Braud, H. J.

1986-01-01T23:59:59.000Z

302

Global warming impacts of ozone-safe refrigerants and refrigeration, heating, and air-conditioning technologies  

SciTech Connect

International agreements mandate the phase-out of many chlorine containing compounds that are used as the working fluid in refrigeration, air-conditioning, and heating equipment. Many of the chemical compounds that have been proposed, and are being used in place of the class of refrigerants eliminated by the Montreal Protocol are now being questioned because of their possible contributions to global warming. Natural refrigerants are put forth as inherently superior to manufactured refrigerants because they have very low or zero global warming potentials (GWPs). Questions are being raised about whether or not these manufactured refrigerants, primarily hydrofluorocarbons (HFCs), should be regulated and perhaps phased out in much the same manner as CFCs and HCFCs. Several of the major applications of refrigerants are examined in this paper and the results of an analysis of their contributions to greenhouse warming are presented. Supermarket refrigeration is shown to be an application where alternative technologies have the potential to reduce emissions of greenhouse gases (GHG) significantly with no clear advantage to either natural or HFC refrigerants. Mixed results are presented for automobile air conditioners with opportunities to reduce GHG emissions dependent on climate and comfort criteria. GHG emissions for hermetic and factory built systems (i.e. household refrigerators/freezers, unitary equipment, chillers) are shown to be dominated by energy use with much greater potential for reduction through efficiency improvements than by selection of refrigerant. The results for refrigerators also illustrate that hydrocarbon and carbon dioxide blown foam insulation have lower overall effects on GHG emissions than HFC blown foams at the cost of increased energy use.

Fischer, S.; Sand, J.; Baxter, V.

1997-12-01T23:59:59.000Z

303

THE MULTI-USE STEINEL VARIABLE TEMPERATURE  

E-Print Network (OSTI)

THE MULTI-USE STEINEL VARIABLE TEMPERATURE ELECTRONICALLY CONTROLLED HEAT GUNTEMPERATURE RANGE 212 COMBUSTIBLE LIQUIDS. DO NOT USE FOR: · Heating gas engines · Heating car batteries · Thawing refrigerator equipment Specifications Temperature Variable from 212° F to 1100° F Watts 1500W Weight 1.5 lbs. Supply

Kleinfeld, David

304

THE MULTI-USE STEINEL VARIABLE TEMPERATURE  

E-Print Network (OSTI)

THE MULTI-USE STEINEL VARIABLE TEMPERATURE ELECTRONICALLY CONTROLLED HEAT GUNTEMPERATURE RANGE 212 COMBUSTIBLE LIQUIDS. DO NOT USE FOR: · Heating gas engines · Heating car batteries · Thawing refrigerator equipment Specifications Temperature Variable from 212" F to 1100° F Watts 1500W Weight 1.5 lbs. Supply

Kleinfeld, David

305

Previous work conducted in the laboratory demonstrated optimal control of refrigerant flow and airflow for a breadboard CVSHP (Miller 1987a). This previous work was continued in the present study by investigation  

E-Print Network (OSTI)

#12;Previous work conducted in the laboratory demonstrated optimal control of refrigerant flow optimal refrigerant flow and airflow control settings. Previous studies by Tanaka and Yamanaka (1982 pump were replaced with fine metering hand valves having variable flow area for both heating

Oak Ridge National Laboratory

306

Testing executive function models of ADHD and its comorbid conditions: A latent variable approach  

E-Print Network (OSTI)

Current theoretical models of ADHD (i.e., Disinhibition Model: Barkley, 1997; Working Memory Model: Rapport et al., 2001) conceptualize ADHD as the disorder of executive function (EF) with some variation in their emphases on particular components of the broadly-defined EF (e.g., working memory vs. inhibition) and in their postulated relationships with ADHD symptoms. Although these models provide systematic accounts of the manifestation of ADHD, they have not been extensively tested from an empirical standpoint. Moreover, despite the fact that ADHD is highly comorbid with other additional conditions such as learning and behavioral problems and EF deficits are found in individuals with these conditions as well as in those with ADHD, current EF models have not specified the developmental relationship between ADHD and its comorbid conditions. This study was: (1) to examine the extent to which two current models of ADHD are supported in a sample of 102 adults; (2) to present an ??integrated?? model by combining two current models of ADHD and linking them to recent research findings on two common comorbid conditions with ADHD (i.e., reading difficulty and substance abuse); and (3) to test and revise such an integrated model in the light of data using a latent variable analysis. Major findings provided a strong support for the Working Memory Model with a lesser degree of support for the Disinhibition Model. Preliminary evidence of working memory as the primary deficit in ADHD was also obtained in the present sample. Finally, the integrated EF model and its revised model (final model) demonstrated a very good fit to the data. These findings suggest that the integrated model provides a unified account of how EF deficits contribute to the manifestation of ADHD symptoms and comorbid conditions with ADHD. Given some limitations (e.g., sample size and scope) of the present study, current findings need to be replicated.

Lee, Dong Hyung

2004-08-01T23:59:59.000Z

307

Bubble Pump Design for Single Pressure Absorption Refrigeration Cycles  

E-Print Network (OSTI)

A model has been developed for the design and optimization of a small bubble pump to be used in a single pressure absorption refrigeration cycle to lift the working fluid mixture against gravity and overcome flow friction. This analytical model is developed from two-phase flow fundamentals and incorporates the design parameters of the bubble pump. Parametric studies are carried out and a design optimization for maximum efficiency is performed for various operating conditions. Optimum efficiency is defined as the liquid pumped per unit of bubble pump heat input. The results show the optimum bubble pump tube diameter over a range of operating conditions.

Sam V. Shelton; Susan White Stewart

2002-01-01T23:59:59.000Z

308

High Efficiency Low Emission Supermarket Refrigeration Research Project |  

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

High Efficiency Low Emission Supermarket High Efficiency Low Emission Supermarket Refrigeration Research Project High Efficiency Low Emission Supermarket Refrigeration Research Project The U.S. Department of Energy (DOE) is currently conducting research into high efficiency, low emission supermarket refrigeration technologies. Project Description The project involves the development of a supermarket refrigeration system that can reduce greenhouse gas emissions and energy consumption when compared to existing systems. The challenge is to design a system that is capable of achieving low refrigerant leak rates while significantly reducing both the energy consumption and the refrigerant charge size. Project Partners Research is being undertaken between DOE and Oak Ridge National Laboratory. Project Goals

309

Opportunities for Energy Efficiency and Automated Demand Response in Industrial Refrigerated Warehouses in California  

E-Print Network (OSTI)

system. The refrigeration system design involves sizing ofDesign Essentials for Refrigerated Storage Facilities, American Society for Heating Refrigeration anddesign considerations are mostly related to wall and roof types, shell insulation, and the refrigeration

Lekov, Alex

2009-01-01T23:59:59.000Z

310

Comparison of Several Eco-Friendly Refrigeration Technologies  

E-Print Network (OSTI)

In this paper, the operation principles, thermodynamics characteristics, and technical practicability were compared between thermoelectric refrigeration, magnetic refrigeration and adsorption refrigeration. The TE refrigeration is the most well-developed, applicable and competitive technology. Three eco-friendly refrigeration systems are increasingly getting attention, especially in a day with increasingly energy and environmental crises. In summary, thermoelectric refrigeration possesses the following superiorities: a longer developmental period, more perfect techniques, increasing applications, a larger range of refrigerating capacity, and a better economic property in small refrigerating capacity. Thermoelectric refrigeration cannot be replaced in special fields, and its applications have received more and more attention in recovering waste heat. Magnetic refrigeration has been widely applied in lower temperature regions; its application in middle temperature regions is juvenile. In particular, there is no application of this technique in high temperature regions. Adsorption refrigeration is practical only in near room temperatures. Its advantage is that it can be used in some fields where conventional refrigeration cannot be applied, such as in the application of solar energy, geothermal energy, and other renewable energy, and the recovery of residual and waste heat.? Supported by the Young Foundation of Central South University of Forestry & Technology (06002A) The disadvantages are as follows: the cost is expensive, no practical technique is available at present, and thus, it possesses no general superiority versus other refrigeration technologies.

Tang, C.; Luo, Q.; Li, X.; Zhu, X.

2006-01-01T23:59:59.000Z

311

End-Use Load and Consumer Assessment Program: Analysis of residential refrigerator/freezer performance  

SciTech Connect

The Bonneville Power Administration (Bonneville) is conducting a large end-use data acquisition program in an effort to understand how energy is utilized in buildings with permanent electric space heating equipment in the Pacific Northwest. The initial portion of effort, known as the End-Use Load and Consumer Assessment Program (ELCAP), was conducted for Bonneville by the Pacific Northwest Laboratory (PNL). The collection of detailed end-use data provided an opportunity to analyze the amount of energy consumed by both refrigerators and separate freezers units located in residential buildings. By obtaining this information, the uncertainty of long- term regional end-use forecasting can be improved and potential utility marketing programs for new appliances with a reduced overall energy demand can be identified. It was found that standby loads derived from hourly averages between 4 a.m. and 5 a.m. reflected the minimum consumption needed to maintain interior refrigerator temperatures at a steady-state condition. Next, an average 24-hour consumption that included cooling loads from door openings and cooling food items was also determined. Later, analyses were conducted to develop a model capable of predicting refrigerator standby loads and 24-hour consumption for comparison with national refrigerator label ratings. Data for 140 residential sites with a refrigeration end-use were screened to develop a sample of 119 residences with pure refrigeration for use in this analysis. To identify those refrigerators that were considered to be pure (having no other devices present on the circuit) in terms of their end-use classification, the screening procedure used a statistical clustering technique that was based on standby loads with 24-hour consumption. 5 refs., 18 figs., 4 tabs.

Ross, B.A.

1991-09-01T23:59:59.000Z

312

Potential Refrigerants for Power Electronics Cooling  

DOE Green Energy (OSTI)

In the past, automotive refrigerants have conventionally been used solely for the purpose of air conditioning. However, with the development of hybrid-electric vehicles and the incorporation of power electronics (PEs) into the automobile, automotive refrigerants are taking on a new role. Unfortunately, PEs have lifetimes and functionalities that are highly dependent on temperature and as a result thermal control plays an important role in the performance of PEs. Typically, PEs are placed in the engine compartment where the internal combustion engine (ICE) already produces substantial heat. Along with the ICE heat, the additional thermal energy produced by PEs themselves forces designers to use different cooling methods to prevent overheating. Generally, heat sinks and separate cooling loops are used to maintain the temperature. Disturbingly, the thermal control system can consume one third of the total volume and may weigh more than the PEs [1]. Hence, other avenues have been sought to cool PEs, including submerging PEs in automobile refrigerants to take advantage of two-phase cooling. The objective of this report is to explore the different automotive refrigerants presently available that could be used for PE cooling. Evaluation of the refrigerants will be done by comparing environmental effects and some thermo-physical properties important to two-phase cooling, specifically measuring the dielectric strengths of potential candidates. Results of this report will be used to assess the different candidates with good potential for future use in PE cooling.

Starke, M.R.

2005-10-24T23:59:59.000Z

313

Energy Consumption of Refrigerators in Ghana - Outcomes of Household  

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

Energy Consumption of Refrigerators in Ghana - Outcomes of Household Energy Consumption of Refrigerators in Ghana - Outcomes of Household Surveys Speaker(s): Essel Ben Hagan Date: July 12, 2007 - 12:00pm Location: 90-3122 Seminar Host/Point of Contact: Robert Van Buskirk Galen Barbose As part of activities to develop refrigerator efficiency standards regulations in Ghana, a national survey on the energy consumption of refrigerators and refrigerator-freezers has been conducted. The survey covered 1000 households in urban, peri-urban and rural communities in various parts of the country. The survey found that, on average, refrigerators and refrigerator-freezers in Ghana use almost three times what is allowed by minimum efficiency standards in the U.S., and a few refrigerators had energy use at levels almost ten times the U.S.

314

Loveland Water and Power - Refrigerator Recycling Program | Department of  

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

Refrigerator Recycling Program Refrigerator Recycling Program Loveland Water and Power - Refrigerator Recycling Program < Back Eligibility Residential Savings Category Appliances & Electronics Maximum Rebate Limit one rebate per account per year Program Info State Colorado Program Type Utility Rebate Program Rebate Amount Refrigerator and Freezer Recycling: $35 Loveland Water and Power is providing an incentive for its customers to recycle their old refrigerators. Interested customers can call the utility to arrange a time to pick up the old refrigerator. The old refrigerator should be brought outside but remain plugged in so the utility can make it is in working condition. the utility will then take the refrigerator to a recycling facility and issue a $35 bill credit. Other Information

315

Refrigerator Standards Save Consumers $ Billions | Department of Energy  

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

Refrigerator Standards Save Consumers $ Billions Refrigerator Standards Save Consumers $ Billions Refrigerator Standards Save Consumers $ Billions March 5, 2013 - 10:35am Addthis Refrigerator Standards Refrigerator Standards Refrigerator technology has come a long way since Dr. John Gorrie (1803 - 1855), a forward-looking inventor, was granted U. S. Patent #8080 for mechanical refrigeration in 1851. In those days, ice was expensive, if it was even available: Blocks of natural ice were carved from frozen lakes and rivers and stored in special warehouses under layers of sawdust for insulation. By the 1890s, pollution and sewage dumping caused by population growth compromised sources of pure, natural ice, threatening the brewing, meat-packing, and dairy industries. As these and other industries sought better solutions, modern refrigeration technology started to evolve.

316

DOE Resolves Avanti Refrigerator and Freezer Civil Penalty Case  

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

Today, the Department of Energy announced that it has resolved the civil penalty action against Mackle Company for its failure to certify that refrigerators and refrigerator-freezers sold under the...

317

VEE-0079 - In the Matter of Diversified Refrigeration, Inc.  

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

Diversified Refrigeration, Inc. (DRI) requests a six-month exception from the 2001 energy appliance efficiency standards for built-in refrigerators that become effective July 1, 2001. As explained...

318

Integrating giant microwave absorption with magnetic refrigeration in one  

E-Print Network (OSTI)

Integrating giant microwave absorption with magnetic refrigeration in one multifunctional with magnetic refrigeration in one multifunctional material. This integration not only advances our EMI problem, it is becoming very urgent to design and fabricate the electromagnetic compatibility (EMC

Wang, Wei Hua

319

Thermoelectric refrigerator having improved temperature-stabilization means  

DOE Patents (OSTI)

A control system for thermoelectric refrigerators is disclosed. The thermoelectric refrigerator includes at least one thermoelectric element that undergoes a first order change at a predetermined critical temperature. The element functions as a thermoelectric refrigerator element above the critical temperature but discontinuously ceases to function as a thermoelectric refrigerator element below the critical temperature. One example of such an arrangement includes thermoelectric refrigerator elements which are superconductors. The transition temperature of one of the superconductor elements is selected as the temperature control point of the refrigerator. When the refrigerator attempts to cool below the point, the metals become superconductors losing their ability to perform as a thermoelectric refrigerator. An extremely accurate, first-order control is realized.

Falco, C.M.

1981-07-29T23:59:59.000Z

320

Modelling the asymmetric wind of the luminous blue variable binary MWC 314  

E-Print Network (OSTI)

We present a spectroscopic analysis of MWC 314, a luminous blue variable (LBV) candidate with an extended bipolar nebula. The detailed spectroscopic variability is investigated to determine if MWC 314 is a massive binary system with a supersonically accelerating wind or a low-mass B[e] star. We compare the spectrum and spectral energy distribution to other LBVs (such as P Cyg) and find very similar physical wind properties, indicating strong kinship. We combined long-term high-resolution optical spectroscopic monitoring and V-band photometric observations to determine the orbital elements and stellar parameters and to investigate the spectral variability with the orbital phases. We developed an advanced model of the large-scale wind-velocity and wind-density structure with 3-D radiative transfer calculations that fit the orbitally modulated P Cyg profile of He I lam5876, showing outflow velocities above 1000 km/s. We find that MWC 314 is a massive semi-detached binary system of ~1.22 AU, observed at an inclin...

Lobel, A; Martayan, C; Frémat, Y; Dozinel, K Torres; Raskin, G; Van Winckel, H; Prins, S; Pessemier, W; Waelkens, C; Hensberge, H; Dummortier, L; Jorissen, A; Van Eck, S; Lehmann, H

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

A Variable-Resolution Semi-Lagrangian Finite-Element Global Model of the Shallow-Water Equations  

Science Conference Proceedings (OSTI)

To meet the needs of short- and medium-range operational forecasting, the authors propose a unified strategy based on the use of a global variable-resolution model, run in two different configurations. These are as follows: (i) a variable-...

Jean Côté; Michel Roch; Andrew Staniforth; Luc Fillion

1993-01-01T23:59:59.000Z

322

Model of variable speed constant frequency double fed wind power generation system and analysis of its operating performance  

Science Conference Proceedings (OSTI)

Structure of variable speed constant frequency double fed wind power generation system (WPGS) was analyzed, and its model was established. Maximum power point tracking (MPPT) control, constant power control and vector control for WPGS were discussed. ... Keywords: operating performance, variable speed constant frequency, vector control, wind power generation system

Pan Tinglong; Ji Zhicheng

2009-06-01T23:59:59.000Z

323

A simple model to assess the sensitivity of grassland dairy systems to scenarios of seasonal biomass production variability  

Science Conference Proceedings (OSTI)

In recent decades, dairy herds of the peri-Mediterranean area have coped with high climatic variability, which has contributed to weakening their economic equilibrium. Survey studies highlighted that climatic impact depends on the strategies of farmers, ... Keywords: Biomass production variability, Cattle farming system, Modelling, System sensitivity

A. Lurette; C. Aubron; C. -H. Moulin

2013-04-01T23:59:59.000Z

324

Internal Versus SST-Forced Atmospheric Variability as Simulated by an Atmospheric General Circulation Model  

Science Conference Proceedings (OSTI)

The variability of atmospheric flow is analyzed by separating it into an internal part due to atmospheric dynamics only and an external (or forced) part due to the variability of sea surface temperature forcing. The two modes of variability are ...

Ali Harzallah; Robert Sadourny

1995-03-01T23:59:59.000Z

325

Variability of the South Atlantic Convergence Zone Simulated by an Atmospheric General Circulation Model  

Science Conference Proceedings (OSTI)

Interannual and decadal variability of the South Atlantic convergence zone (SACZ) during austral summer [season January–February–March (JFM)] is investigated. An attempt is made to separate the forced variability from the internal variability. ...

Marcelo Barreiro; Ping Chang; R. Saravanan

2002-04-01T23:59:59.000Z

326

High Efficiency Low Emission Supermarket Refrigeration Research Project  

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

The U.S. Department of Energy (DOE) is currently conducting research into high efficiency, low emission supermarket refrigeration technologies.

327

Of Refrigerators & Regulations | Department of Energy  

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

Of Refrigerators & Regulations Of Refrigerators & Regulations Of Refrigerators & Regulations February 8, 2011 - 9:29am Addthis Jesse Lee White House Director of Online Affairs Editor's Note: This entry has been cross-posted from The White House Blog. For those interested in the President's remarks to the U.S. Chamber of Commerce and his views on the shared responsibilities of government and business to the American people, our post earlier will give a suitable overview. For those interested in the details of the President's Executive Order on reviewing regulations and their impacts on the economy, Cass Sunstein's post this morning will also be of value. But the President also took a moment during his speech to put the debate over regulation in a different perspective, and to break through the false dichotomy so often

328

Energy Saving with Absorption Refrigeration Technologies  

E-Print Network (OSTI)

Absorption refrigeration technology can be an economical and cost effective means of reducing energy cost and/or improving the efficiency and output of your process. We believe the potential benefits of absorption refrigeration technology have generally been overlooked by the process industry. This paper will address the application of the lithium bromide-water cycle in various energy saving modes. A waste heat powered absorption chiller producing chilled water can reduce energy consumption in a process plant by replacing an existing mechanical refrigeration system or replacing cooling tower water with a lower temperature cooling medium at negligible increase in energy cost. A variety of waste heat sources can be used at temperatures as low as 150 F.

Davis, R. C.

1984-01-01T23:59:59.000Z

329

Hyperspectral remote sensing of plant biochemistry using Bayesian model averaging with variable and band selection  

SciTech Connect

Model specification remains challenging in spectroscopy of plant biochemistry, as exemplified by the availability of various spectral indices or band combinations for estimating the same biochemical. This lack of consensus in model choice across applications argues for a paradigm shift in hyperspectral methods to address model uncertainty and misspecification. We demonstrated one such method using Bayesian model averaging (BMA), which performs variable/band selection and quantifies the relative merits of many candidate models to synthesize a weighted average model with improved predictive performances. The utility of BMA was examined using a portfolio of 27 foliage spectral–chemical datasets representing over 80 species across the globe to estimate multiple biochemical properties, including nitrogen, hydrogen, carbon, cellulose, lignin, chlorophyll (a or b), carotenoid, polar and nonpolar extractives, leaf mass per area, and equivalent water thickness. We also compared BMA with partial least squares (PLS) and stepwise multiple regression (SMR). Results showed that all the biochemicals except carotenoid were accurately estimated from hyerspectral data with R2 values > 0.80.

Zhao, Kaiguang; Valle, Denis; Popescu, Sorin; Zhang, Xuesong; Malick, Bani

2013-05-15T23:59:59.000Z

330

Multiscale Modeling of Polycrystalline Magnetostrictive Alloy Galfenol  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... Different Generations of Gamma Prime Precipitates in a Commercial Nickel ...

331

How small can thermal machines be? The smallest possible refrigerator  

E-Print Network (OSTI)

We investigate the fundamental dimensional limits to thermodynamic machines. In particular we show that it is possible to construct self-contained refrigerators (i.e. not requiring external sources of work) consisting of only a small number of qubits and/or qutrits. We present three different models, consisting of two qubits, a qubit and a qutrit with nearest-neighbour interactions, and a single qutrit respectively. We then investigate fundamental limits to their performance; in particular we show that it is possible to cool towards absolute zero.

Noah Linden; Sandu Popescu; Paul Skrzypczyk

2009-08-14T23:59:59.000Z

332

Toxicity Data to Determine Refrigerant Concentration Limits  

SciTech Connect

This report reviews toxicity data, identifies sources for them, and presents resulting exposure limits for refrigerants for consideration by qualified parties in developing safety guides, standards, codes, and regulations. It outlines a method to calculate an acute toxicity exposure limit (ATEL) and from it a recommended refrigerant concentration limit (RCL) for emergency exposures. The report focuses on acute toxicity with particular attention to lethality, cardiac sensitization, anesthetic and central nervous system effects, and other escape-impairing effects. It addresses R-11, R-12, R-22, R-23, R-113, R-114, R-116, R-123, R-124, R-125, R-134, R-134a, R-E134, R-141b, R-142b, R-143a, R-152a, R-218, R-227ea, R-236fa, R-245ca, R-245fa, R-290, R-500, R-502, R-600a, R-717, and R-744. It summarizes additional data for R-14, R-115, R-170 (ethane), R-C318, R-600 (n-butane), and R-1270 (propylene) to enable calculation of limits for blends incorporating them. The report summarizes the data a nd related safety information, including classifications and flammability data. It also presents a series of tables with proposed ATEL and RCL concentrations-in dimensionless form and the latter also in both metric (SI) and inch-pound (IP) units of measure-for both the cited refrigerants and 66 zerotropic and azeotropic blends. They include common refrigerants, such as R-404A, R-407C, R-410A, and R-507A, as well as others in commercial or developmental status. Appendices provide profiles for the cited single-compound refrigerants and for R-500 and R-502 as well as narrative toxicity summaries for common refrigerants. The report includes an extensive set of references.

Calm, James M.

2000-09-30T23:59:59.000Z

333

ENVIRONMENTAL ASSESSMENT FOR THE PROPOSED ENERGY CONSERVATION STANDARD FOR REFRIGERATORS, REFRIGERATOR-  

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

ASSESSMENT FOR THE PROPOSED ENERGY ASSESSMENT FOR THE PROPOSED ENERGY CONSERVATION STANDARD FOR REFRIGERATORS, REFRIGERATOR- , AND FREEZERS - 1. INTRODUCTION AND NEED FOR PROPOSED ACTION ental Assessment (EA) on the candidate energy conservation stand licy Act. of 1969 (NEPA), regulations of the Council on Environmentd Qu refrigerators, re€iigerator-freezers, and freezers was prepared pursuant to the National ' ederal Regulations, Parts 1500 through. 1508. The proposed energy conservation standard (Level 1) and the alternative standards are being reviewed in an energy- efficiency standards rulemaking that the Department has undertaken pursuant to the Energy Policy and Conservation Act, as amended by the National Energy Conservation Policy Act and the National Appliance Energy Consehation Act

334

Reducing the Carbon Footprint of Commercial Refrigeration Systems Using Life Cycle Climate Performance Analysis: From System Design to Refrigerant Options  

SciTech Connect

In this paper, Life Cycle Climate Performance (LCCP) analysis is used to estimate lifetime direct and indirect carbon dioxide equivalent gas emissions of various refrigerant options and commercial refrigeration system designs, including the multiplex DX system with various hydrofluorocarbon (HFC) refrigerants, the HFC/R744 cascade system incorporating a medium-temperature R744 secondary loop, and the transcritical R744 booster system. The results of the LCCP analysis are presented, including the direct and indirect carbon dioxide equivalent emissions for each refrigeration system and refrigerant option. Based on the results of the LCCP analysis, recommendations are given for the selection of low GWP replacement refrigerants for use in existing commercial refrigeration systems, as well as for the selection of commercial refrigeration system designs with low carbon dioxide equivalent emissions, suitable for new installations.

Fricke, Brian A [ORNL; Abdelaziz, Omar [ORNL; Vineyard, Edward Allan [ORNL

2013-01-01T23:59:59.000Z

335

ASHRAE/NIST Refrigerants Conference International concerns about the impact of refrigerants on climate change drive the  

E-Print Network (OSTI)

ASHRAE/NIST Refrigerants Conference International concerns about the impact of refrigerants conference between ASHRAE and NIST. Supporting Organizations: NOTE: Registration closes Oct. 18 and includes conference proceedings, daily lunch and dinner Monday evening. ASHRAE Members: $425 Non

Fernández-Juricic, Esteban

336

Refrigeration needs for sustainable preservation of horticultural products  

Science Conference Proceedings (OSTI)

Fresh horticultural products are highly perishable and need refrigeration for further preservation. Refrigeration needs energy consumption with consequent economical cost and damage for the environment. The objective of the present work was to use efficiently ... Keywords: energy efficiency, food salads, halophytes, postharvest technologies, refrigeration, safe food, sustainability

Custódia Gago; Ana Rita Sousa; Miriam Julião; Graça Miguel; Dulce Antunes; Thomas Panagopoulos

2011-02-01T23:59:59.000Z

337

HANDLING FRESH FISH REFRIGERATION OF FISH -PART 2  

E-Print Network (OSTI)

(Fishery Leaflet 427) Cold-Storage Design and Refrigeration Equipment Part 3 (Fisher y Leaflet 429) FactorsHANDLING FRESH FISH REFRIGERATION OF FISH - PART 2 UNITED STATES DEPARTMENT OF THE INTERIOR FISH 428 Washington 25, D, C. December 1956 REFRIGERATION OF FISH - PART TWO HANDLING FRESH FISH By Charles

338

A Comparison of the Variability of a Climate Model with Paleotemperature Estimates from a Network of Tree-Ring Densities  

Science Conference Proceedings (OSTI)

Validation of the decadal to centennial timescale variability of coupled climate models is limited by the scarcity of long observational records. Proxy indicators of climate, such as tree rings, ice cores, etc., can be utilized for this purpose. ...

Matthew Collins; Timothy J. Osborn; Simon F. B. Tett; Keith R. Briffa; Fritz H. Schweingruber

2002-07-01T23:59:59.000Z

339

Phenomenology of the Low-Frequency Variability in a Reduced-Gravity, Quasigeostrophic Double-Gyre Model  

Science Conference Proceedings (OSTI)

The low-frequency variability of the oceanic wind-driven circulation is investigated by use of a reduced-gravity, quasigeostrophic model with slight variations on the classic double-gyre wind forcing. Approximately 30 eddy-resolving simulations ...

John D. McCalpin; Dale B. Haidvogel

1996-05-01T23:59:59.000Z

340

Principal Modes of Atmospheric Variability in Model Atmospheres with and without Anomalous Sea Surface Temperature Forcing in the Tropical Pacific  

Science Conference Proceedings (OSTI)

Principal modes of low-frequency atmospheric variability and the influence of sea surface temperature anomalies on such modes are investigated by examining the output from two general circulation model experiments. In the first experiment (the “...

In-Sik Kang; Ngar-Cheung Lau

1986-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Interdecadal and Interannual Variability in the Northern Extratropical Circulation Simulated with the JMA Global Model. Part I: Wintertime Leading Mode  

Science Conference Proceedings (OSTI)

Interdecadal and interannual atmospheric variability in the extratropical Northern Hemisphere is investigated using an atmospheric GCM. The model used for this research is a T42 GCM version of the Japan Meteorological Agency (JMA-GSM89) global ...

Ryuichi Kawamura; Masato Sugi; Nobuo Sato

1995-12-01T23:59:59.000Z

342

The Mid-Quaternary Climatic Transition as the Free Response of a Three-Variable Dynamical Model  

Science Conference Proceedings (OSTI)

A simplified version of a previously described dynamical model governing global ice mass, atmospheric carbon dioxide, and mean ocean temperature (that may also be a proxy for some other CO2–controlling oceanic variable, e.g., nutrient supply) is ...

Barry Saltzman; Alfonso Sutera

1987-01-01T23:59:59.000Z

343

Decadal Sea Level Variability in the South Pacific in a Global Eddy-Resolving Ocean Model Hindcast  

Science Conference Proceedings (OSTI)

Sea level variability and related oceanic changes in the South Pacific from 1970 to 2003 are investigated using a hindcast simulation of an eddy-resolving ocean general circulation model (OGCM) for the Earth Simulator (OFES), along with sea level ...

Yoshi N. Sasaki; Shoshiro Minobe; Niklas Schneider; Takashi Kagimoto; Masami Nonaka; Hideharu Sasaki

2008-08-01T23:59:59.000Z

344

Global Retrospective Estimation of Soil Moisture Using the Variable Infiltration Capacity Land Surface Model, 1980–93  

Science Conference Proceedings (OSTI)

A daily set of surface meteorological forcings, model-derived surface moisture fluxes, and state variables for global land areas for the period of 1979–93 is described. The forcing dataset facilitates global simulations and evaluation of land ...

Bart Nijssen; Reiner Schnur; Dennis P. Lettenmaier

2001-04-01T23:59:59.000Z

345

Retrofitting Doors on Open Refrigerated Cases  

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

Retrofitting Doors on Open Retrofitting Doors on Open Refrigerated Cases William Goetzler Navigant Consulting, Inc. wgoetzler@navigant.com (781) 270-8351 April 4, 2013 BBA Refrigeration Project Team Images courtesy of REMIS AMERICA, LLC. 2 | Building Technologies Office eere.energy.gov Technology Overview Image from Investigation of Energy- Efficient Supermarket Display Cases. 2004, Oak Ridge National Laboratory. Background and Motivation * Adding doors to open cases (retrofits) greatly reduces cold air loss - 50-80% load reduction - Load reduction = system energy savings

346

Plate Fin Heat Exchanger Model with Axial Conduction and Variable Properties  

Science Conference Proceedings (OSTI)

Future superconducting radio frequency (SRF) cavities, as part of Project X at Fermilab, will be cooled to superfluid helium temperatures by a cryogenic distribution system supplying cold supercritical helium. To reduce vapor fraction during the final Joule-Thomson (J-T) expansion into the superfluid helium cooling bath, counter-flow, plate-fin heat exchangers will be utilized. Due to their compact size and ease of fabrication, plate-fin heat exchangers are an effective option. However, the design of compact and high-effectiveness cryogenic heat exchangers operating at liquid helium temperatures requires consideration of axial heat conduction along the direction of flow, in addition to variable fluid properties. Here we present a numerical model that includes the effects of axial conduction and variable properties for a plate fin heat exchanger. The model is used to guide design decisions on heat exchanger material choice and geometry. In addition, the J-T expansion process is modeled with the heat exchanger to analyze the effect of heat load and cryogenic supply parameters. A numerical model that includes the effects of axial conduction and variable properties for a plate fin heat exchanger was developed and the effect of various design parameters on overall heat exchanger size was investigated. It was found that highly conductive metals should be avoided in the design of compact JT heat exchangers. For the geometry considered, the optimal conductivity is around 3.5 W/m-K and can range from 0.3-10 W/m-K without a large loss in performance. The model was implemented with an isenthalpic expansion process. Increasing the cold side inlet temperature from 2K to 2.2 K decreased the liquid fraction from 0.856 to 0.839 which corresponds to a 0.12 g/s increase in supercritical helium supply needed to maintain liquid level in the cooling bath. Lastly, it was found that the effectiveness increased when the heat load was below the design value. Therefore, the heat exchanger should be sized on the high end of the required heat load.

Hansen, B.J.; White, M.J.; Klebaner, A.; /Fermilab

2011-06-10T23:59:59.000Z

347

Final Report: Climate Variability, Stochasticity and Learning in Integrated Assessment Models, September 15, 1996 - September 14, 1999  

SciTech Connect

The focus of the work has been on climate variability and learning within computational climate-economy models (integrated assessment models--IAM's). The primary objective of the research is to improve the representation of learning in IAM's. This include's both endogenous and exogenous learning. A particular focus is on Bayesian learning about climate damage. A secondary objective is to improve the representation of climate variability within IAM's.

Kolstad, Charles D.

1999-09-14T23:59:59.000Z

348

Evaluation of design options for improving the energy efficiency of an environmentally safe domestic refrigerator-freezer  

SciTech Connect

In order to reduce greenhouse emissions from power plants and respond to regulatory actions arising from the National Appliance Energy Conservation Act (NAECA), several design options were investigated for improving the energy efficiency of a conventionally designed, domestic refrigerator-freezer. The options, such as improved cabinet insulation and high-efficiency compressor and fans, were incorporated into a prototype refrigerator-freezer cabinet and refrigeration system to produce a unit that is superior from an environmental viewpoint due to its lower energy consumption and the use of refrigerant HFC-134a as a replacement for CFC-12. Baseline energy performance of the original 1993 production refrigerator-freezer, along with cabinet heat load and compressor calorimeter test results, were extensively documented to provide a firm basis for experimentally measured energy savings. A detailed refrigerator system computer model was used to evaluate the energy savings for several design modifications that, collectively, could achieve a targeted energy consumption of 1.00 kWh/d for a 20 ft{sup 3} (570 l) top-mount, automatic-defrost, refrigerator-freezer. The energy consumption goal represents a 50% reduction in the 1993 NAECA standard for units of this size. Following the modeling simulation, laboratory prototypes were fabricated and tested to experimentally verify the analytical results and aid in improving the model in those areas where discrepancies occurred. While the 1.00 kWh/d goal was not achieved with the modifications, a substantial energy efficiency improvement of 22% (1.41 kWh/d) was demonstrated using near-term technologies. It is noted that each improvement exacts a penalty in terms of increased cost or system complexity/reliability. Further work on this project will analyze cost-effectiveness of the design changes and investigate alternative, more-elaborate, refrigeration system changes to further reduce energy consumption.

Vineyard, E.A.; Sand, J.R. [Oak Ridge National Lab., TN (United States); Bohman, R.H.

1995-03-01T23:59:59.000Z

349

Floating Loop System For Cooling Integrated Motors And Inverters Using Hot Liquid Refrigerant  

DOE Patents (OSTI)

A floating loop vehicle component cooling and air-conditioning system having at least one compressor for compressing cool vapor refrigerant into hot vapor refrigerant; at least one condenser for condensing the hot vapor refrigerant into hot liquid refrigerant by exchanging heat with outdoor air; at least one floating loop component cooling device for evaporating the hot liquid refrigerant into hot vapor refrigerant; at least one expansion device for expanding the hot liquid refrigerant into cool liquid refrigerant; at least one air conditioning evaporator for evaporating the cool liquid refrigerant into cool vapor refrigerant by exchanging heat with indoor air; and piping for interconnecting components of the cooling and air conditioning system.

Hsu, John S [Oak Ridge, TN; Ayers, Curtis W [Kingston, TN; Coomer, Chester [Knoxville, TN; Marlino, Laura D [Oak Ridge, TN

2006-02-07T23:59:59.000Z

350

Carbon Dioxide and Ionic Liquid Refrigerants: Compact, Efficient Air Conditioning with Ionic Liquid-Based Refrigerants  

SciTech Connect

BEETIT Project: Notre Dame is developing an air-conditioning system with a new ionic liquid and CO2 as the working fluid. Synthetic refrigerants used in air conditioning and refrigeration systems are potent GHGs and can trap 1,000 times more heat in the atmosphere than CO2 alone—making CO2 an attractive alternative for synthetic refrigerants in cooling systems. However, operating cooling systems with pure CO2 requires prohibitively high pressures and expensive hardware. Notre Dame is creating a new fluid made of CO2 and ionic liquid that enables the use of CO2 at low pressures and requires minimal changes to existing hardware and production lines. This new fluid also produces no harmful emissions and can improve the efficiency of air conditioning systems— enabling new use of CO2 as a refrigerant in cooling systems.

2010-10-01T23:59:59.000Z

351

Performance simulation of R410A air conditioning system with variable speeds  

Science Conference Proceedings (OSTI)

With the implementation of "Montreal protocol on substances that deplete the ozone layer", HCFCs especially R22 will be phased out. R410A (R32/R125,50/50wt%), as one alternative of R22, is a promising refrigerant for air conditioning ... Keywords: R410A, air conditioning, electronic expansion valve, performance, refrigerants, system simulation, variable speeds

Zaoxiao Zhang; Yongzhang Yu; Leping Zhang

2004-12-01T23:59:59.000Z

352

International Refrigeration: Proposed Penalty (2012-CE-1510) | Department  

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

International Refrigeration: Proposed Penalty (2012-CE-1510) International Refrigeration: Proposed Penalty (2012-CE-1510) International Refrigeration: Proposed Penalty (2012-CE-1510) July 9, 2012 DOE alleged in a Notice of Proposed Civil Penalty that International Refrigeration Products failed to certify a various room air conditioners as compliant with the applicable energy conservation standards. DOE regulations require a manufacturer (which includes importers) to submit reports certifying that its products have been tested and meet the applicable energy conservation standards. This civil penalty notice advises the company of the potential penalties and DOE's administrative process, including the company's right to a hearing. International Refrigeration: Proposed Penalty (2012-CE-1510) More Documents & Publications

353

Refrigeration in a world without CFCs  

Science Conference Proceedings (OSTI)

In an era of heightened awareness of energy efficiency and the associated environmental impacts, many industries, worldwide, are exploring ``environmentally friendly`` technologies that provide equivalent or improved performance while reducing or eliminating harmful side effects. The refrigeration and air conditioning industry, due to its reliance on CFCs and HCFCs has invested in research in alternatives to the industry standard vapor compression machines. One alternative technology with great promise is chemical absorption. Absorption chillers offer comparable refrigeration output with reduced SO{sub 2}, CO{sub 2}, and NO{sub x} emissions. Additionally, absorption chillers do not use CFCs or HCFCs, refrigerants that contribute to ozone depletion and global warming. The purpose of this paper is to provide an introduction for those new to absorption technology as well as a discussion of selected high efficiency cycles and environmental impacts for those familiar with absorption. The introduction will include a brief history of absorption and a description of the basic refrigeration cycle, while the advanced sections will discuss triple-effect technology and a life-cycle or ``systems`` approach to evaluating global warming impacts.

Garland, R.W. [U.S. Dept. of Energy, Washington D.C. (United States); Adcock, P.W. [Oak Ridge National Lab., TN (United States)

1996-09-01T23:59:59.000Z

354

Waste Heat Recapture from Supermarket Refrigeration Systems  

DOE Green Energy (OSTI)

The objective of this project was to determine the potential energy savings associated with improved utilization of waste heat from supermarket refrigeration systems. Existing and advanced strategies for waste heat recovery in supermarkets were analyzed, including options from advanced sources such as combined heat and power (CHP), micro-turbines and fuel cells.

Fricke, Brian A [ORNL

2011-11-01T23:59:59.000Z

355

On the performance of ejector refrigeration systems  

Science Conference Proceedings (OSTI)

The design characteristics of an ejector refrigeration system using R134a with fixed cooling capacity and fixed inlet temperatures of the external fluids at the inlet of the generator, the condenser and the evaporator are presented for different pressures ... Keywords: COP, R-134a, computer simulation, finite size thermodynamics

Abdelouahid Dahmani; Zine Aidoun; Nicolas Galanis

2010-02-01T23:59:59.000Z

356

Building Technologies Office: Low-Global Warming Potential Refrigerants  

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

Low-Global Warming Low-Global Warming Potential Refrigerants Research Project to someone by E-mail Share Building Technologies Office: Low-Global Warming Potential Refrigerants Research Project on Facebook Tweet about Building Technologies Office: Low-Global Warming Potential Refrigerants Research Project on Twitter Bookmark Building Technologies Office: Low-Global Warming Potential Refrigerants Research Project on Google Bookmark Building Technologies Office: Low-Global Warming Potential Refrigerants Research Project on Delicious Rank Building Technologies Office: Low-Global Warming Potential Refrigerants Research Project on Digg Find More places to share Building Technologies Office: Low-Global Warming Potential Refrigerants Research Project on AddThis.com... About Take Action to Save Energy

357

Dilution cycle control for an absorption refrigeration system  

DOE Patents (OSTI)

A dilution cycle control system for an absorption refrigeration system is disclosed. The control system includes a time delay relay for sensing shutdown of the absorption refrigeration system and for generating a control signal only after expiration of a preselected time period measured from the sensed shutdown of the absorption refrigeration system, during which the absorption refrigeration system is not restarted. A dilution cycle for the absorption refrigeration system is initiated in response to generation of a control signal by the time delay relay. This control system is particularly suitable for use with an absorption refrigeration system which is frequently cycled on and off since the time delay provided by the control system prevents needless dilution of the absorption refrigeration system when the system is turned off for only a short period of time and then is turned back on.

Reimann, Robert C. (Lafayette, NY)

1984-01-01T23:59:59.000Z

358

Effect of surface conditions on boiling heat transfer of refrigerants in shell-and-tube evaporators  

Science Conference Proceedings (OSTI)

Experimental results are presented for the boiling heat transfer performance of R 22 and R 717 on surfaces with porous metallized coatings. A calculational-theoretical model is given for predicting the heat transfer of refrigerants boiling on a bundle of finned tubes.

Danilova, G.N.; Dyundin, V.A.; Borishanskaya, A.V.; Soloviyov, A.G.; Vol'nykh, Y.A.; Kozyrev, A.A.

1990-01-01T23:59:59.000Z

359

An inhomogeneous jet model for the rapid variability of TeV blazars  

E-Print Network (OSTI)

We present a new time-dependent inhomogeneous jet model of non-thermal blazar emission, which reproduces the entire spectral energy distribution together with the rapid gamma-ray variability. Ultra-relativistic leptons are injected at the base of a jet and propagate along the jet structure. We assume continuous reacceleration and cooling, producing a relativistic quasi-maxwellian (or "pile-up") particle energy distribution. The synchrotron and Synchrotron-Self Compton jet emissivity are computed at each altitude. Klein-Nishina effects as well as intrinsic gamma-gamma absorption are included in the computation. Due to the pair production optical depth, considerable particle density enhancement can occur, particularly during flaring states. Time-dependent jet emission can be computed by varying the particle injection, but due to the sensitivity of pair production process, only small variations of the injected density are required during the flares. The stratification of the jet emission, together with a pile-up distribution, allows significantly lower bulk Lorentz factors, compared to one-zone models. Applying this model to the case of PKS2155-304 and its big TeV flare observed in 2006, we can reproduce simultaneously the average broad band spectrum of this source as well as the TeV spectra and TeV light curve of the flare with bulk Lorentz factor lower than 15.

Timothé Boutelier; Gilles Henri; Pierre-Olivier Petrucci

2008-07-31T23:59:59.000Z

360

A Variable-Resolution Stretched-Grid General Circulation Model: Regional Climate Simulation  

Science Conference Proceedings (OSTI)

The development of and results obtained with a variable-resolution stretched-grid GCM for the regional climate simulation mode are presented. A global variable-resolution stretched grid used in the study has enhanced horizontal resolution over ...

Michael S. Fox-Rabinovitz; Lawrence L. Takacs; Ravi C. Govindaraju; Max J. Suarez

2001-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Modeling, Error Analysis, and Evaluation of Dual-Polarization Variables Obtained from Simultaneous Horizontal and Vertical Polarization Transmit Radar. Part I: Modeling and Antenna Errors  

Science Conference Proceedings (OSTI)

In this two-part paper the biases of polarimetric variables from simultaneous horizontally and vertically transmitted (SHV) data are investigated. Here, in Part I, a radar-scattering model is developed and antenna polarization errors are ...

J. C. Hubbert; S. M. Ellis; M. Dixon; G. Meymaris

2010-10-01T23:59:59.000Z

362

Variably Saturated Flow and Multicomponent Biogeochemical Reactive Transport Modeling of a Uranium Bioremediation Field Experiment  

Science Conference Proceedings (OSTI)

Field experiments at a former uranium mill tailings site have identified the potential for stimulating indigenous bacteria to catalyze the conversion of aqueous uranium in the +6 oxidation state to immobile solid-associated uranium in the +4 oxidation state. This effectively removes uranium from solution resulting in groundwater concentrations below actionable standards. Three-dimensional, coupled variably-saturated flow and biogeochemical reactive transport modeling of a 2008 in situ uranium bioremediation field experiment is used to better understand the interplay of transport rates and biogeochemical reaction rates that determine the location and magnitude of key reaction products. A comprehensive reaction network, developed largely through previous 1-D modeling studies, was used to simulate the impacts on uranium behavior of pulsed acetate amendment, seasonal water table variation, spatially-variable physical (hydraulic conductivity, porosity) and geochemical (reactive surface area) material properties. A principal challenge is the mechanistic representation of biologically-mediated terminal electron acceptor process (TEAP) reactions whose products significantly alter geochemical controls on uranium mobility through increases in pH, alkalinity, exchangeable cations, and highly reactive reduction products. In general, these simulations of the 2008 Big Rusty acetate biostimulation field experiment in Rifle, Colorado confirmed previously identified behaviors including (1) initial dominance by iron reducing bacteria that concomitantly reduce aqueous U(VI), (2) sulfate reducing bacteria that become dominant after {approx}30 days and outcompete iron reducers for the acetate electron donor, (3) continuing iron-reducer activity and U(VI) bioreduction during dominantly sulfate reducing conditions, and (4) lower apparent U(VI) removal from groundwater during dominantly sulfate reducing conditions. New knowledge on simultaneously active metal and sulfate reducers has been incorporated into the modeling. In this case, an initially small population of slow growing sulfate reducers is active from the initiation of biostimulation. Three-dimensional, variably saturated flow modeling was used to address impacts of a falling water table during acetate injection. These impacts included a significant reduction in aquifer saturated thickness and isolation of residual reactants and products, as well as unmitigated uranium, in the newly unsaturated vadose zone. High permeability sandy gravel structures resulted in locally high flow rates in the vicinity of injection wells that increased acetate dilution. In downgradient locations, these structures created preferential flow paths for acetate delivery that enhanced local zones of TEAP reactivity and subsidiary reactions. Conversely, smaller transport rates associated with the lower permeability lithofacies (e.g., fine) and vadose zone were shown to limit acetate access and reaction. Once accessed by acetate, however, these same zones limited subsequent acetate dilution and provided longer residence times that resulted in higher concentrations of TEAP products when terminal electron donors and acceptors were not limiting. Finally, facies-based porosity and reactive surface area variations were shown to affect aqueous uranium concentration distributions; however, the ranges were sufficiently small to preserve general trends. Large computer memory and high computational performance were required to simulate the detailed coupled process models for multiple biogeochemical components in highly resolved heterogeneous materials for the 110-day field experiment and 50 days of post-biostimulation behavior. In this case, a highly-scalable subsurface simulator operating on 128 processor cores for 12 hours was used to simulate each realization. An equivalent simulation without parallel processing would have taken 60 days, assuming sufficient memory was available.

Yabusaki, Steven B.; Fang, Yilin; Williams, Kenneth H.; Murray, Christopher J.; Ward, Anderson L.; Dayvault, Richard; Waichler, Scott R.; Newcomer, Darrell R.; Spane, Frank A.; Long, Philip E.

2011-11-01T23:59:59.000Z

363

Analysis of Mass Flow and Enhanced Mass Flow Methods of Flashing Refrigerant-22 from a Small Vessel  

E-Print Network (OSTI)

The mass flow characteristics of flashing Refrigerant-22 from a small vessel were investigated. A flash boiling apparatus was designed and built. It was modeled after the flashing process encountered by the accumulator of air-source heat pump systems. Three small pyrex glass vessels were used to hold the refrigerant and allow for visualization studies of the flashing process. Baseline experiments were run varying initial pressure, initial refrigerant amount, orifice diameter, and vessel geometry. Three sets of experiments were run using two passive enhancement methods (the addition of steel balls and the addition of small amounts of oil) and one active enhancement method (the addition of an immersion heater). Furthermore, a lumped-parameter analytical model was developed from basic thermodynamic principles that predicted the rate of depressurization for the flashing refrigerant. The study showed that the initial refrigerant amount and the orifice size had the greatest influence on the mass flow and pressure characteristics during each sixty second test. The initial pressure and vessel volume had less of an impact under the conditions tested. Two of the enhancement methods consistently increased the amount of refrigerant flashed during the tests as compared to the baseline data for the same initial conditions. The addition a 1 cm layer of 3.6 mm steel balls to the base of the vessel increased the amount flashed from 21% to 81% and the addition of the 215-watt flat-spiral immersion heater the increased the amount flashed from 47% to 111 %. Foaming at the vapor-liquid interface was observed with the refrigerant-oil mixture experiments as two of the eight test conditions averaged an increase while six averaged a decrease, ranging from a 21% increase to a 27% decrease. The analytical depressurization model predicted general pressure and mass flux trends, and revisions to the model improved pressure predictions to within ±11%.

Nutter, Darin Wayne

1994-12-01T23:59:59.000Z

364

China Refrigerator Information Label: Specification Development and Potential Impact  

SciTech Connect

In the last five years, China's refrigerator market has grown rapidly, and now urban markets are showing signs of saturation, with ownership rates in urban households reaching 92%. Rural markets continue to grow from a much lower base. As a result of this growth, the Chinese government in 2006 decided to revise the refrigerator standards and its associated efficiency grades for the mandatory energy information label. In the Chinese standards process, the efficiency grades for the information label are tied to the minimum standards. Work on the minimum standards revision began in 2006 and continued through the first half of 2007, when the draft standard was completed under the direction of the China National Institute of Standardization (CNIS). Development of the information label grades required consideration of stakeholder input, continuity with the previous grade classification, ease of implementation, and potential impacts on the market. In this process, CLASP, with the support of METI/IEEJ, collaborated with CNIS to develop the efficiency grades, providing technical input to the process, comment and advice on particular technical issues, and evaluation of the results. After three months of effort and three drafts of the final grade specifications, this work was completed. In addition, in order to effectively evaluate the impact of the label on China's market, CLASP further provided assistance to CNIS to collect data on both the efficiency distribution and product volume distribution of refrigerators on the market. The new information label thresholds to be implemented in 2008 maintain the approach first adopted in 2005 of establishing efficiency levels relative to the minimum standard, but increased the related required efficiency levels by 20% over those established in 2003 and implemented in 2005. The focus of improvement was on the standard refrigerator/freezer (class 5), which constitutes the bulk of the Chinese market. Indeed, the new requirements to achieve grade 1 on the label are now virtually as stringent as those for US Energy Star-qualified or EU A-grade refrigerators. When the energy information label went into effect in March 2005, refrigerator manufacturers were required to display their declared level of efficiency on the label and report it to the China Energy Label Center (CELC), a newly established unit of CNIS responsible for label program management. Because of the visible nature of the label, it was found, through a METI/IEEJ-supported study, that MEPS non-compliance dropped from 4% to zero after the label became mandatory, and that the percentage of higher-grade refrigerators increased. This suggests that the label itself does have potential for shifting the market to higher-efficiency models (Lin 2007). One challenge, however, of assessing this potential impact is the lack of a comprehensive baseline of market efficiency and a program to evaluate the market impact on a yearly basis. As a result, the impact evaluation in this study draws upon the market transformation experience of the related EU energy information label, for which quantitative assessments of its market impact exist. By assuming a parallel process unfolding in China, it is possible to look at the potential impact of the label to 2020. The results of the analysis demonstrates that a robust market transformation program in China focused on the energy information label could save substantial amounts of electricity by 2020, totaling 16.4 TWh annually by that year, compared to a case in which the efficiency distribution of refrigerators was frozen at the 2007 level. Remarkably, the impact of a successful market transformation program with the label would essentially flatten the consumption of electricity for refrigerator use throughout most of the next decade, despite the expectations of continued growth in total stock by nearly 190 million units. At the end of this period, total consumption begins to rise again, as the least efficient of the units have been mostly removed from the market. Such a level of savings would redu

Fridley, David; Fridley, David; Zheng, Nina; Zhou, Nan; Aden, Nathaniel; Lin, Jiang; Jianhong, Cheng; Sakamoto, Tomoyuki

2008-02-01T23:59:59.000Z

365

Prediction of autoignition in a lifted methane/air flame using an unsteady flamelet/progress variable model  

Science Conference Proceedings (OSTI)

An unsteady flamelet/progress variable (UFPV) model has been developed for the prediction of autoignition in turbulent lifted flames. The model is a consistent extension to the steady flamelet/progress variable (SFPV) approach, and employs an unsteady flamelet formulation to describe the transient evolution of all thermochemical quantities during the flame ignition process. In this UFPV model, all thermochemical quantities are parameterized by mixture fraction, reaction progress parameter, and stoichiometric scalar dissipation rate, eliminating the explicit dependence on a flamelet time scale. An a priori study is performed to analyze critical modeling assumptions that are associated with the population of the flamelet state space. For application to LES, the UFPV model is combined with a presumed PDF closure to account for subgrid contributions of mixture fraction and reaction progress variable. The model was applied in LES of a lifted methane/air flame. Additional calculations were performed to quantify the interaction between turbulence and chemistry a posteriori. Simulation results obtained from these calculations are compared with experimental data. Compared to the SFPV results, the unsteady flamelet/progress variable model captures the autoignition process, and good agreement with measurements is obtained for mixture fraction, temperature, and species mass fractions. From the analysis of scatter data and mixture fraction-conditional results it is shown that the turbulence/chemistry interaction delays the ignition process towards lower values of scalar dissipation rate, and a significantly larger region in the flamelet state space is occupied during the ignition process. (author)

Ihme, Matthias; See, Yee Chee [Department of Aerospace Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)

2010-10-15T23:59:59.000Z

366

Combined transmission distribution load flow model employing system reduction and voltage variable load representation  

SciTech Connect

In the few decades since its introduction the digital computer has found widespread application within the electric power industry. One of the more fruitful areas for its utilization has been in the determination of the steady-state voltage conditions throughout the system. A power system naturally breaks down into two very distinct parts: transmission and distribution, and traditionally, the voltage problem has been separated the same way. In the transmission system it is referred to as a load flow problem, and in the distribution part it is called a voltage profile. In addition, the loads are often treated differently. Transmission loads are usually considered to be constant power, and the equations that result are therefore nonlinear. In the distribution portion the loads, though specified in terms of power, are sometimes handled as constant impedances, with linear equations. This work produced a new model wherein a mesh transmission system is combined with a radial distribution system and they are solved simultaneously. A system reduction technique is used to eliminate part of the transmission system from consideration, and thereby keep the problem at a manageable size. The solution algorithm incorporates a voltage variable load model which approximates the behavior of real loads more nearly than the common representations.

Enouen, P.W.

1985-01-01T23:59:59.000Z

367

REFRIGERANT-BASED PROPULSION SYSTEM FOR SMALL SPACECRAFT  

E-Print Network (OSTI)

The MR SAT spacecraft under development at UMR requires a propulsion system that can be utilized to perform orbital maneuvers and three-axis attitude control to complete its mission objective of conducting spacecraft formation flight. This thesis documents the research, analysis design and development of the cold gas propulsion system that was integrated in the MR SAT spacecraft. The basis of design and safety requirements stemmed from the AFRL University Nanosat Program competition, in which the UMR SAT project placed third out of eleven schools from across the nation. The MR SAT propulsion system was a primary feature as it implements a refrigerant (R-134a) propellant that has never been flown in space. As detailed in this thesis, through engineering modeling and laboratory testing R-134a is demonstrated to be a feasible propellant for small spacecraft. As the R-134a is stored as a saturated liquid in the tank, it was necessary to analyze the thermodynamic properties of the refrigerant and investigate phase changes for its use as a propellant. Also documented is the hardware selected and the integration into the MR SAT spacecraft, along with the laboratory testing

Carl Reiner Seubert; Dr. Kelly; O. Homan

2007-01-01T23:59:59.000Z

368

Combined Phase Field-Potts Model for Grain Growth and ...  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... Different Generations of Gamma Prime Precipitates in a Commercial Nickel ...

369

Modeling and Simulation of Process-Structure-Property of ...  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... Different Generations of Gamma Prime Precipitates in a Commercial Nickel ...

370

Integrated Modeling of Tundish and Continuous Caster to Meet ...  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... Different Generations of Gamma Prime Precipitates in a Commercial Nickel ...

371

Elastoplastic Phase Field Model for Time-Dependent Hydrogen ...  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... of Gamma Prime Precipitates in a Commercial Nickel Base Superalloy.

372

PolymerModeler Tool at NanoHUB.org  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... Different Generations of Gamma Prime Precipitates in a Commercial Nickel ...

373

Modelling the Process Chain of Microalloyed Case Hardening Steel ...  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... of Gamma Prime Precipitates in a Commercial Nickel Base Superalloy.

374

Preliminary selection of refrigerants for dual-circuit and Lorenz refrigerator/freezers  

SciTech Connect

The paper discusses the preliminary selection of refrigerants for dual-circuit and Lorenz refrigerator/freezers (RFs). Since RFs currently use a fully halogenated chlorofluorocarbon (CFC) as a refrigerant and are the most energy-consuming appliances in most households in the U.S., EPA is concerned about not only RFs' effects on stratospheric ozone depletion but also their impact on the greenhouse effect. Reductions in power consumption will slow the increase in carbon dioxide (CO{sub 2}) concentrations in the atmosphere by reducing the utility companies' need for capacity. CO{sub 2} concentrations are believed to be directly related to impacts of the greenhouse effect. For these reasons, EPA believes that finding the most energy-efficient refrigerant(s) and RF design is important when eliminating fully halogenated CFCs. Two new configurations (the dual-circuit and Lorenz RFs) appear to provide energy savings of up to 20% over standard U.S. RF designs.

Bare, J.C.

1990-01-01T23:59:59.000Z

375

International Refrigeration: Order (2012-CE-1510)  

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

WASHINGTON, D.C. 20585 WASHINGTON, D.C. 20585 Case Number: 2012-CE-1510 International Refrigeration Products, Respondent ) ) ) ) ) ) ORDER Issued: July 20, 2012 By the General Counsel, U.S. Department of Energy: 1. In this Order, I adopt the attached Compromise Agreement entered into between the U.S. Department of Energy ("DOE") and International Refrigeration Products ("Respondent"). The Compromise Agreement resolves the case initiated to pursue a civil penalty for violations of the compliance certification requirements located at 10 C.P.R. § 429.12. 2. DOE and Respondent have negotiated the terms of the Compromise Agreement that resolve this matter. A copy of the Compromise Agreement is attached hereto and incorporated by reference. 3. After reviewing the terms of the Compromise Agreement and evaluating the facts

376

SCREW COMPRESSOR CHARACTERISTICS FOR HELIUM REFRIGERATION SYSTEMS  

SciTech Connect

The oil injected screw compressors have practically replaced all other types of compressors in modern helium refrigeration systems due to their large displacement capacity, minimal vibration, reliability and capability of handling helium's high heat of compression.At the present state of compressor system designs for helium systems, typically two-thirds of the lost input power is due to the compression system. Therefore it is important to understand the isothermal and volumetric efficiencies of these machines to help properly design these compression systems to match the refrigeration process. This presentation summarizes separate tests that have been conducted on Sullair compressors at the Superconducting Super-Collider Laboratory (SSCL) in 1993, Howden compressors at Jefferson Lab (JLab) in 2006 and Howden compressors at the Spallation Neutron Source (SNS) in 2006. This work is part of an ongoing study at JLab to understand the theoretical basis for these efficiencies and their loss

Ganni, Venkatarao; Knudsen, Peter; Creel, Jonathan; Arenius, Dana; Casagrande, Fabio; Howell, Matt

2008-03-01T23:59:59.000Z

377

The Climatology of the Middle Atmosphere in a Vertically Extended Version of the Met Office’s Climate Model. Part II: Variability  

Science Conference Proceedings (OSTI)

Stratospheric variability is examined in a vertically extended version of the Met Office global climate model. Equatorial variability includes the simulation of an internally generated quasi-biennial oscillation (QBO) and semiannual oscillation (...

Scott M. Osprey; Lesley J. Gray; Steven C. Hardiman; Neal Butchart; Andrew C. Bushell; Tim J. Hinton

2010-11-01T23:59:59.000Z

378

Improving Industrial Refrigeration System Efficiency - Actual Applications  

E-Print Network (OSTI)

This paper discusses actual design and modifications for increased system efficiency and includes reduced chilled liquid flow during part load operation, reduced condensing and increased evaporator temperatures for reduced system head, thermosiphon cycle cooling during winter operation, compressor intercooling, direct refrigeration vs. brine cooling, insulation of cold piping to reduce heat gain, multiple screw compressors for improved part load operation, evaporative condensers for reduced system head and pumping energy, and using high efficiency motors.

White, T. L.

1980-01-01T23:59:59.000Z

379

A Method for On-Going Commissioning of VRV Package Systems Using a Simulation Model  

E-Print Network (OSTI)

Variable refrigerant volume (VRV) systems, which have several indoor units and a single outdoor unit, have become very popular HVAC systems in Japan. However, some systems may be operated under inefficient conditions and consume excessive energy, since verification of system performance is not conducted. Although the performance of systems should be evaluated by some indices such as coefficient of performance (COP), calculating such a value is difficult, because the heat load handled by machines is not known. A simulation model based on a refrigeration cycle was proposed to evaluate system performance. Basic conditions for evaporation and condensation were defined from conditions provided in Japanese Industrial Standards (JIS). Flow rate of refrigerant was calculated from heat load under full occupancy and enthalpy difference of the evaporator. If power consumption exceeds the calculated value, malfunctions or inadequate conditions are considered to occur. The method presented here can be used for on-going commissioning of VRV package systems.

Yamaha, M.; Sekiyama, K.; Misaki, S.

2006-01-01T23:59:59.000Z

380

Could You Save Money on Your Refrigerator? | Department of Energy  

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

Could You Save Money on Your Refrigerator? Could You Save Money on Your Refrigerator? Could You Save Money on Your Refrigerator? July 20, 2012 - 4:35pm Addthis Earlier this week, Amanda wrote about how you can save energy by choosing the right refrigerator and using it efficiently. These tips explain all sorts of ways you can ensure your refrigerator uses as little energy as possible to keep itself cool. So this week, we're curious: Could you save money with your refrigerator? You have the chance to share your thoughts on a question about energy efficiency or renewable energy for consumers. E-mail your responses to the Energy Saver team at consumer.webmaster@nrel.gov. Addthis Related Articles How Do You Save Money on Summer Holidays? Have You Seen Energy Efficiency Improvements in Your Neighborhood?

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Method of reducing chlorofluorocarbon refrigerant emissons to the atmosphere  

DOE Patents (OSTI)

A method is disclosed for reducing chloroflurocarbon (CFC) refrigerant emissions during removal or transfer or refrigerants from a vapor compression cooling system or heat pump which comprises contacting the refrigerant with a suitable sorbent material. The sorbent material allows for the storage and retention or the chlorofluorocarbon in non-gaseous form so that it does not tend to escape to the atmosphere where it would cause harm by contributing to ozone depletion. In other aspects of the invention, contacting of CFC refrigerants with sorbent material allows for purification and recycling of used refrigerant, and a device containing stored sorbent material can be employed in the detection of refrigerant leakage in a cooling system or heat pump.

DeVault, Robert C. (Knoxville, TN); Fairchild, Phillip D. (Clinton, TN); Biermann, Wendell J. (Fayetteville, NY)

1990-01-01T23:59:59.000Z

382

Optimal Design Refrigeration System for a Mucilage Glue Fiber Factory  

E-Print Network (OSTI)

In a mucilage glue fiber factory, the design of the refrigeration system takes into account the characteristics of mucilage glue fiber production and fully uses the refrigeration compressor heat to economize energy and reduce the production cost. In this paper, the author introduces different points of this kind of design with conventional design. For efficient use of the compressed heat of the refrigeration system, the designer should calculate the number of condensers according to the changes that the refrigeration system undergoes after using the soft water as cooling water. To economize the investment, the designer should use the refrigeration workshop and the soft water workshop and obtain optimum processing to shorten the duct. Through an economizing energy analysis, the paper demonstrates that an optimum design for a refrigeration system for a mucilage glue factory has a significant energy saving potential.

Tan, C.; Liu, J.; Tang, F.; Liu, Y.

2006-01-01T23:59:59.000Z

383

Could You Save Money on Your Refrigerator? | Department of Energy  

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

Could You Save Money on Your Refrigerator? Could You Save Money on Your Refrigerator? Could You Save Money on Your Refrigerator? July 20, 2012 - 4:35pm Addthis Earlier this week, Amanda wrote about how you can save energy by choosing the right refrigerator and using it efficiently. These tips explain all sorts of ways you can ensure your refrigerator uses as little energy as possible to keep itself cool. So this week, we're curious: Could you save money with your refrigerator? You have the chance to share your thoughts on a question about energy efficiency or renewable energy for consumers. E-mail your responses to the Energy Saver team at consumer.webmaster@nrel.gov. Addthis Related Articles How Do You Save Money on Summer Holidays? Have You Seen Energy Efficiency Improvements in Your Neighborhood?

384

Air Conditioning with Magnetic Refrigeration : An Efficient, Green Compact Cooling System Using Magnetic Refrigeration  

SciTech Connect

BEETIT Project: Astronautics is developing an air conditioning system that relies on magnetic fields. Typical air conditioners use vapor compression to cool air. Vapor compression uses a liquid refrigerant to circulate within the air conditioner, absorb the heat, and pump the heat out into the external environment. Astronautics’ design uses a novel property of certain materials, called “magnetocaloric materials”, to achieve the same result as liquid refrigerants. These magnetocaloric materials essentially heat up when placed within a magnetic field and cool down when removed, effectively pumping heat out from a cooler to warmer environment. In addition, magnetic refrigeration uses no ozone-depleting gases and is safer to use than conventional air conditioners which are prone to leaks.

None

2010-09-01T23:59:59.000Z

385

Energy conservation for household refrigerators and water heaters  

Science Conference Proceedings (OSTI)

An energy conservation arrangement for household refrigerators and water heaters, in which the source of cold water to the hot water heater is divided and part is caused to flow through and be warmed in the condenser of the refrigerator. The warmed water is then further heated in the oil cooling loop of the refrigerator compressor, and proceeds then to the top of the hot water tank.

Speicher, T. L.

1984-12-11T23:59:59.000Z

386

Studies of regional-scale climate variability and change: Hidden Markov models and coupled ocean-atmosphere modes  

SciTech Connect

In this project we developed further a twin approach to the study of regional-scale climate variability and change. The two approaches involved probabilistic network (PN) models (sometimes called dynamic Bayesian networks) and intermediate-complexity coupled ocean-atmosphere models (ICMs). We thus made progress in identifying the predictable modes of climate variability and investigating their impacts on the regional scale. In previous work sponsored by DOE�s Climate Change Prediction Program (CCPP), we had developed a family of PNs (similar to Hidden Markov Models) to simulate historical records of daily rainfall, and used them to downscale seasonal predictions of general circulation models (GCMs). Using an idealized atmospheric model, we had established a novel mechanism through which ocean-induced sea-surface temperature (SST) anomalies might in�uence large-scale atmospheric circulation patterns on interannual and longer time scales; similar patterns were found in a hybrid coupled ocean�atmosphere�sea-ice model. In this continuation project, we built on these ICM results and PN model development to address prediction of rainfall and temperature statistics at the local scale, associated with global climate variability and change, and to investigate the impact of the latter on coupled ocean�atmosphere modes. Our main project results consist of extensive further development of the hidden Markov models for rainfall simulation and downscaling together with the development of associated software; new intermediate coupled models; a new methodology of inverse modeling for linking ICMs with observations and GCM simulations, called empirical mode reduction (EMR); and observational studies of decadal and multi-decadal natural climate variability, informed by ICM simulations. A particularly timely by-product of this work is an extensive study of clustering of cyclone tracks in the extratropical Atlantic and the western Tropical Pacific, with potential applications to predicting landfall.

M. Ghil (UCLA), PI; S. Kravtsov (UWM); A. W. Robertson (IRI); P. Smyth (UCI)

2008-10-14T23:59:59.000Z

387

Active magnetic refrigerants based on Gd-Si-Ge material and refrigeration apparatus and process  

DOE Patents (OSTI)

Active magnetic regenerator and method using Gd.sub.5 (Si.sub.x Ge.sub.1-x).sub.4, where x is equal to or less than 0.5, as a magnetic refrigerant that exhibits a reversible ferromagnetic/antiferromagnetic or ferromagnetic-II/ferromagnetic-I first order phase transition and extraordinary magneto-thermal properties, such as a giant magnetocaloric effect, that renders the refrigerant more efficient and useful than existing magnetic refrigerants for commercialization of magnetic regenerators. The reversible first order phase transition is tunable from approximately 30 K to approximately 290 K (near room temperature) and above by compositional adjustments. The active magnetic regenerator and method can function for refrigerating, air conditioning, and liquefying low temperature cryogens with significantly improved efficiency and operating temperature range from approximately 10 K to 300 K and above. Also an active magnetic regenerator and method using Gd.sub.5 (Si.sub.x Ge.sub.1-x).sub.4, where x is equal to or greater than 0.5, as a magnetic heater/refrigerant that exhibits a reversible ferromagnetic/paramagnetic second order phase transition with large magneto-thermal properties, such as a large magnetocaloric effect that permits the commercialization of a magnetic heat pump and/or refrigerant. This second order phase transition is tunable from approximately 280 K (near room temperature) to approximately 350 K by composition adjustments. The active magnetic regenerator and method can function for low level heating for climate control for buildings, homes and automobile, and chemical processing.

Gschneidner, Jr., Karl A. (Ames, IA); Pecharsky, Vitalij K. (Ames, IA)

1998-04-28T23:59:59.000Z

388

Active magnetic refrigerants based on Gd-Si-Ge material and refrigeration apparatus and process  

DOE Patents (OSTI)

Active magnetic regenerator and method using Gd{sub 5} (Si{sub x}Ge{sub 1{minus}x}){sub 4}, where x is equal to or less than 0.5, as a magnetic refrigerant that exhibits a reversible ferromagnetic/antiferromagnetic or ferromagnetic-II/ferromagnetic-I first order phase transition and extraordinary magneto-thermal properties, such as a giant magnetocaloric effect, that renders the refrigerant more efficient and useful than existing magnetic refrigerants for commercialization of magnetic regenerators. The reversible first order phase transition is tunable from approximately 30 K to approximately 290 K (near room temperature) and above by compositional adjustments. The active magnetic regenerator and method can function for refrigerating, air conditioning, and liquefying low temperature cryogens with significantly improved efficiency and operating temperature range from approximately 10 K to 300 K and above. Also an active magnetic regenerator and method using Gd{sub 5} (Si{sub x} Ge{sub 1{minus}x}){sub 4}, where x is equal to or greater than 0.5, as a magnetic heater/refrigerant that exhibits a reversible ferromagnetic/paramagnetic second order phase transition with large magneto-thermal properties, such as a large magnetocaloric effect that permits the commercialization of a magnetic heat pump and/or refrigerant. This second order phase transition is tunable from approximately 280 K (near room temperature) to approximately 350 K by composition adjustments. The active magnetic regenerator and method can function for low level heating for climate control for buildings, homes and automobile, and chemical processing. 27 figs.

Gschneidner, K.A. Jr.; Pecharsky, V.K.

1998-04-28T23:59:59.000Z

389

Geothermal: Sponsored by OSTI -- Chapter 13. Absorption Refrigeration  

Office of Scientific and Technical Information (OSTI)

GEOTHERMAL TECHNOLOGIES LEGACY COLLECTION - Sponsored by OSTI -- Chapter 13. Absorption Refrigeration Geothermal Technologies Legacy Collection HelpFAQ | Site Map | Contact Us |...

390

Economizer refrigeration cycle space heating and cooling system and process  

DOE Patents (OSTI)

This invention relates to heating and cooling systems and more particularly to an improved system utilizing a Stirling Cycle engine heat pump in a refrigeration cycle. 18 figs.

Jardine, D.M.

1983-03-22T23:59:59.000Z

391

Thermal Analysis of Refrigeration Systems Used for Vaccine ...  

Science Conference Proceedings (OSTI)

... may result from planned HVAC outages at night or ... recording data after the refrigerator was powered. ... the length of the power outage and the ...

2012-08-02T23:59:59.000Z

392

Electric, Gas, Water, Heating, Refrigeration, and Street Railways...  

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

and Street Railways Facilities and Service (South Dakota) Electric, Gas, Water, Heating, Refrigeration, and Street Railways Facilities and Service (South Dakota) < Back...

393

The Ghana Refrigerator Efficiency Initiative - An Overview of...  

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

refrigeration services the most expensive of energy services in residential Ghanaian households, posing serious financial burden on households. --The problem that this project...

394

Purchase of newer refrigerators slows during economic downturn ...  

U.S. Energy Information Administration (EIA)

Sales data from the Association of Home Appliance ... Decreasing sales of new refrigerators means slower adoption of new energy-efficient technology and less ...

395

Energy Efficiency Standards for Refrigerators in Brazil: A Methodology...  

Open Energy Info (EERE)

It uses a bottom-up approach to estimate residential end-use consumption and evaluate the energy saving potential for refrigerators. References Retrieved from "http:...

396

Federal Energy Management Program: New and Underutilized Refrigeration...  

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

Power Management, and Vending Machine Technologies to someone by E-mail Share Federal Energy Management Program: New and Underutilized Refrigeration, Computer Power Management,...

397

Sustainable design of hydrocarbon refrigerants applied to the hermetic compressor.  

E-Print Network (OSTI)

??International environmental concern led to the control and phase out of traditional chlorofluorocarbon refrigerants (CFCs) under the terms of the Montreal protocol. CFCs used in… (more)

Garland, Nigel P.

2004-01-01T23:59:59.000Z

398

Magnetocaloric Refrigeration Concepts: Current State of the Art  

Science Conference Proceedings (OSTI)

Abstract Scope, Refrigeration devices based on the magnetocaloric effect have been ... Some of the major design choices are then evaluated and, based on ...

399

Refrigerator Efficiency in Ghana: Tailoring an Appliance Market...  

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

Refrigerator Efficiency in Ghana: Tailoring an Appliance Market Transformation Program Design for Africa Publication Type Report LBNL Report Number LBNL-61251 Year of...

400

Enhancement of the Refrigerant Capacity in Partially Crystallized Gd ...  

Science Conference Proceedings (OSTI)

Consequently, the magnetic refrigerant capacity of the partially crystallized alloys is ... Alloy Design and Powder Processing of Mn-Al Based Materials for Rare ...

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Economizer refrigeration cycle space heating and cooling system and process  

DOE Patents (OSTI)

This invention relates to heating and cooling systems and more particularly to an improved system utilizing a Stirling Cycle engine heat pump in a refrigeration cycle.

Jardine, Douglas M. (Colorado Springs, CO)

1983-01-01T23:59:59.000Z

402

DOE Opens Three Investigations into Alleged Refrigerator Efficiency...  

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

The Department of Energy has issued one subpoena and two data requests to three companies in response to allegations that the companies are selling refrigerator-freezers that...

403

List of Commercial Refrigeration Equipment Incentives | Open Energy  

Open Energy Info (EERE)

Refrigeration Equipment Incentives Refrigeration Equipment Incentives Jump to: navigation, search The following contains the list of 103 Commercial Refrigeration Equipment Incentives. CSV (rows 1 - 103) Incentive Incentive Type Place Applicable Sector Eligible Technologies Active AEP Appalachian Power - Commercial and Industrial Rebate Programs (West Virginia) Utility Rebate Program West Virginia Commercial Industrial Central Air conditioners Chillers Custom/Others pending approval Heat pumps Lighting Lighting Controls/Sensors Motor VFDs Programmable Thermostats Commercial Refrigeration Equipment Ground Source Heat Pumps Yes AEP Ohio - Commercial New Construction Energy Efficiency Rebate Program (Ohio) Utility Rebate Program Ohio Commercial Industrial Local Government Municipal Utility

404

Simulated Diurnal Range and Variability of Surface Temperature in a Global Climate Model for Present and Doubled C02 Climates  

Science Conference Proceedings (OSTI)

The variability of surface temperature simulated by a global climate model with a simple mixed-layer ocean is analyzed. The simulated diurnal and seasonal ranges of temperature are compared with observation, as is the day-to-day and interannual ...

Hong Xing Cao; J. F. B. Mitchell; J. R. Lavery

1992-09-01T23:59:59.000Z

405

U.S. Residential Miscellaneous Refrigeration Products: Results from Amazon Mechanical Turk Surveys  

E-Print Network (OSTI)

icemakers and non-vapor compression refrigerators and2.5,+4.5) million non-vapor compression refrigerators inthe existence of non-vapor compression freezers. Moreover,

Greenblatt, Jeffery B.

2013-01-01T23:59:59.000Z

406

Refrigeration system with a compressor-pump unit and a liquid ...  

The refrigeration system includes a compressor-pump unit and/or a liquid-injection assembly. The refrigeration system is a vapor-compression refrigera ...

407

Verification of a level-3 diesel emissions control strategy for transport refrigeration units.  

E-Print Network (OSTI)

??Transport Refrigeration Units (TRUs) are refrigeration systems used to control the environment of temperature sensitive products while they are being transported from one place to… (more)

Shewalla, Umesh.

2010-01-01T23:59:59.000Z

408

Design and Analysis of a Nested Halbach Permanent Magnet Magnetic Refrigerator.  

E-Print Network (OSTI)

??A technology with the potential to create efficient and compact refrigeration devices is an active magnetic regenerative refrigerator (AMRR). AMRRs exploit the magnetocaloric effect displayed… (more)

Tura, Armando

2013-01-01T23:59:59.000Z

409

Inverse Modeling of Intra-annual Variability in the Subtropical North Pacific  

Science Conference Proceedings (OSTI)

Climatological data on the oceanic and atmospheric variability are inverted to study seasonal variation of the Kuroshio Extension (KE) and the recirculation gyre to the south. The processed datasets include climatological fluxes of heat, salt, ...

Max Yaremchuk; Konstantin Lebedev

2002-10-01T23:59:59.000Z

410

Investigation of Hydrological Variability in West Africa Using Land Surface Models  

Science Conference Proceedings (OSTI)

The availability of freshwater is a particularly important issue in Africa where large portions of the continent are arid or semiarid and climate is highly variable. Sustainable water resource management requires the assessment of hydrological ...

K. Y. Li; M. T. Coe; N. Ramankutty

2005-08-01T23:59:59.000Z

411

Development of Regional Models that Use Meteorological Variables for Predicting Stripe Rust Disease on Winter Wheat  

Science Conference Proceedings (OSTI)

Meteorological variables can be used to predict stripe rust, a disease of wheat caused by Puccinia striiformis West., at Lind, Pullman, and Walla Walla, Washington and Pendleton, Oregon in the Pacific Northwest of the United States. Regional ...

Stella Melugin Coakley; William S. Boyd; Roland F. Line

1984-08-01T23:59:59.000Z

412

A Model for the Estimation of Global Solar Radiation Using Fuzzy Random Variables  

Science Conference Proceedings (OSTI)

In this paper, the concept of fuzzy random variables is applied for the estimation of global solar radiation on a surface at ground level. The cloudiness index is defined as the fraction of extraterrestrial radiation that reaches the earth's ...

Nalin K. Gautam; N. D. Kaushika

2002-12-01T23:59:59.000Z

413

Wet Equivalent Potential Temperature and Enthalpy as Prognostic Variables in Cloud Modeling  

Science Conference Proceedings (OSTI)

The bulk thermodynamic consequences of nonreversible phase changes and of the precipitation process are emphasized. Two predictive quantities are proposed, either of which can be used as a prognostic thermodynamic variable, instead of temperature ...

Y. Pointin

1984-02-01T23:59:59.000Z

414

Mechanisms of Decadal Arctic Climate Variability in the Community Climate System Model, Version 2 (CCSM2)  

Science Conference Proceedings (OSTI)

Several mechanisms have been proposed to explain natural climate variability in the Arctic. These include processes related to the influence of the North Atlantic Oscillation/Arctic Oscillation (NAO/AO), anticyclonic/cyclonic regimes, changes in ...

Hugues Goosse; Marika M. Holland

2005-09-01T23:59:59.000Z

415

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

416

Climate Variability and Radiocarbon in the CM2Mc Earth System Model  

Science Conference Proceedings (OSTI)

The distribution of radiocarbon (14C) in the ocean and atmosphere has fluctuated on time scales ranging from seasons to millennia. It is thought that these fluctuations partly reflect variability in the climate system, offering a rich potential ...

Eric D. Galbraith; Eun Young Kwon; Anand Gnanadesikan; Keith B. Rodgers; Stephen M. Griffies; Daniele Bianchi; Jorge L. Sarmiento; John P. Dunne; Jennifer Simeon; Richard D. Slater; Andrew T. Wittenberg; Isaac M. Held

2011-08-01T23:59:59.000Z

417

This is a 1D model of an active magnetic regenerative refrigerator (AMRR) that was developed in MATLAB. The model uses cycle inputs such as the fluid mass flow and  

E-Print Network (OSTI)

temperature profile of the fluid and regenerator. Using the temperature profiles, the cooling load produced in MATLAB. The model uses cycle inputs such as the fluid mass flow and magnetic field profiles, fluid external hardware. The model starts from an initial temperature profile for the regenerator and fluid

Wisconsin at Madison, University of

418

Magnetic refrigeration apparatus with heat pipes  

DOE Patents (OSTI)

A magnetic refrigerator operating in the 4 to 20 K range utilizes heat pipes to transfer heat to and from the magnetic material at the appropriate points during the material's movement. In one embodiment circular disks of magnetic material can be interleaved with the ends of the heat pipes. In another embodiment a mass of magnetic material reciprocatingly moves between the end of the heat pipe or pipes that transmits heat from the object of cooling to the magnetic material and the end of the heat pipe or pipes that transmits heat from the magnetic material to a heat sink.

Barclay, J.A.; Prenger, F.C. Jr.

1985-10-25T23:59:59.000Z

419

Magnetic refrigeration apparatus with heat pipes  

DOE Patents (OSTI)

A magnetic refrigerator operating in the 4 to 20 K range utilizes heat pipes to transfer heat to and from the magnetic material at the appropriate points during the material's movement. In one embodiment circular disks of magnetic material can be interleaved with the ends of the heat pipes. In another embodiment a mass of magnetic material reciprocatingly moves between the end of the heat pipe of pipes that transmits heat from the object of cooling to the magnetic material and the end of the heat pipe or pipes that transmits heat from the magnetic material to a heat sink.

Barclay, John A. (Los Alamos, NM); Prenger, Jr., F. Coyne (Madison, WI)

1987-01-01T23:59:59.000Z

420

Performance monitoring strategies for effective running of commercial refrigeration systems  

Science Conference Proceedings (OSTI)

Refrigeration systems often represent the largest electricity consumers in the supermarkets. Therefore there is a clear need for running these systems effectively. Performance monitoring uses different techniques to determine the actual system state. ... Keywords: COP, FDD, energy monitoring, performance measure, refrigeration

Martin Hrn?ár; Petr Stluka

2010-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Energy efficiency strategies in refrigeration systems of large supermarkets  

Science Conference Proceedings (OSTI)

Energy efficiency and its relationship with sustainable development are one of the most important objectives in modern engineering systems. In Industrial Installations that use refrigeration systems that are associated with the food industry, this optimization ... Keywords: energy efficiency, optimizing parameters, refrigeration systems, supermarkets

J. M. Garcia; L. M. R. Coelho

2010-07-01T23:59:59.000Z

422

Lanthanide Al-Ni base Ericsson cycle magnetic refrigerants  

DOE Patents (OSTI)

A magnetic refrigerant for a magnetic refrigerator using the Ericsson thermodynamic cycle comprises DyAlNi and (Gd{sub 0.54}Er{sub 0.46})AlNi alloys having a relatively constant {Delta}Tmc over a wide temperature range. 16 figs.

Gschneidner, K.A. Jr.; Takeya, Hiroyuki

1995-10-31T23:59:59.000Z

423

Embedded Smart Controller for an Industrial Reefer Refrigeration1  

E-Print Network (OSTI)

refrigeration control. The goal of this project is twofold: to design an efficient and economically feasibleEmbedded Smart Controller for an Industrial Reefer Refrigeration1 Leon Reznik and Shane Spiteri intelligent industrial controller on one hand and to test and further develop a smart device design approach

Reznik, Leon

424

REFRIGERATION OF FISH PART 5 DISTRIBUTION AND MARKETING  

E-Print Network (OSTI)

REFRIGERATION OF FISH· PART 5 DISTRIBUTION AND MARKETING OF FROZEN FISHERY PRODUCTS UNITED STATES in a series of five on "Refrigeration of Fish." Titles of the other four leaflets are: Part 1 (Fishery Leaflet 427) -- Cold-Storage Design and Refrigera- tion Equipnent Part 2 (Fishery Leaflet 428) -- Handling

425

New concepts for refrigerant leak detection and mixture measurement  

Science Conference Proceedings (OSTI)

Since the discovery that chlorofluorocarbons (CFCs) destroy the ozone layer, the need to reduce the release of these refrigerants into the environment has become critical. A total ban of ozone-depleting CFCs is expected within a few years, and hydrofluorocarbons (HFCs) and fluorocarbons (FCs) and their mixtures are expected to be used during a transition period. Several HFC and FC refrigerants are currently being considered as CFC substitutes. The electronic refrigerant leak detectors currently being considered as CFC substitutes. The electronic refrigerant leak detectors currently on the market were developed to detect CFCs and are not as sensitive to HFCs. Although incremental improvement can be made to these devices to detect HFCs, they often lead to increased false signals. Also, there is no simple device available to measure the composition of a refrigerant mixture. The authors present two new concepts to aid in the development of two portable instruments that can be used for HFC leak detection and for quantitative measurement of refrigerant mixture compositions. The development of simple, easy-to-use portable leak detectors and refrigerant mixture meters is essential to the wide use of alternative refrigerants in industry.

Chen, F.C.; Allman, S.L.; Chen, C.H.

1993-12-31T23:59:59.000Z

426

Lanthanide Al-Ni base Ericsson cycle magnetic refrigerants  

DOE Patents (OSTI)

A magnetic refrigerant for a magnetic refrigerator using the Ericsson thermodynamic cycle comprises DyAlNi and (Gd.sub.0.54 Er.sub.0.46)AlNi alloys having a relatively constant .DELTA.Tmc over a wide temperature range.

Gschneidner, Jr., Karl A. (Ames, IA); Takeya, Hiroyuki (Ibaraki, JP)

1995-10-31T23:59:59.000Z

427

Thermodynamic Modeling of the Cu-Hf-Ni System and Its ...  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... Different Generations of Gamma Prime Precipitates in a Commercial Nickel ...

428

Duracold Refrigeration Manufacturing: Proposed Penalty (2013-CE-5342) |  

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

Duracold Refrigeration Manufacturing: Proposed Penalty Duracold Refrigeration Manufacturing: Proposed Penalty (2013-CE-5342) Duracold Refrigeration Manufacturing: Proposed Penalty (2013-CE-5342) February 21, 2013 DOE alleged in a Notice of Proposed Civil Penalty that Duracold Refrigeration Manufacturing Company, LLC failed to certify a variety of walk-in cooler or freezer components as compliant with the applicable energy conservation standards. DOE regulations require a manufacturer (which includes importers) to submit reports certifying that its products have been tested and meet the applicable energy conservation standards. This civil penalty notice advises the company of the potential penalties and DOE's administrative process, including the company's right to a hearing. Duracold Refrigeration Manufacturing: Proposed Penalty (2013-CE-5342)

429

DOE Proposes Higher Efficiency Standards for Refrigerators | Department of  

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

DOE Proposes Higher Efficiency Standards for Refrigerators DOE Proposes Higher Efficiency Standards for Refrigerators DOE Proposes Higher Efficiency Standards for Refrigerators September 28, 2010 - 12:00am Addthis WASHINGTON, DC - U.S. Energy Secretary Steven Chu today announced the release of a new proposed energy efficiency standard for residential refrigerators, refrigerator-freezers, and freezers. The standard, as proposed, could save consumers as much as $18.6 billion over thirty years. The Obama Administration has made efficiency standards a major priority as a way to save energy and money for American families and businesses. Since January 2009, the Department of Energy has finalized new efficiency standards for more than twenty household and commercial products, which will cumulatively save consumers between $250 billion and

430

North Star Refrigerator: Proposed Penalty (2013-CE-5355) | Department of  

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

North Star Refrigerator: Proposed Penalty (2013-CE-5355) North Star Refrigerator: Proposed Penalty (2013-CE-5355) North Star Refrigerator: Proposed Penalty (2013-CE-5355) March 26, 2013 DOE alleged in a Notice of Proposed Civil Penalty that North Star Refrigerator Co., Inc. failed to certify a variety of walk-in cooler or freezer components as compliant with the applicable energy conservation standards. DOE regulations require a manufacturer (which includes importers) to submit reports certifying that its products have been tested and meet the applicable energy conservation standards. This civil penalty notice advises the company of the potential penalties and DOE's administrative process, including the company's right to a hearing. North Star Refrigerator: Proposed Penalty (2013-CE-5355) More Documents & Publications

431

North Star Refrigerator: Proposed Penalty (2013-CE-5355) | Department of  

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

North Star Refrigerator: Proposed Penalty (2013-CE-5355) North Star Refrigerator: Proposed Penalty (2013-CE-5355) North Star Refrigerator: Proposed Penalty (2013-CE-5355) March 26, 2013 DOE alleged in a Notice of Proposed Civil Penalty that North Star Refrigerator Co., Inc. failed to certify a variety of walk-in cooler or freezer components as compliant with the applicable energy conservation standards. DOE regulations require a manufacturer (which includes importers) to submit reports certifying that its products have been tested and meet the applicable energy conservation standards. This civil penalty notice advises the company of the potential penalties and DOE's administrative process, including the company's right to a hearing. North Star Refrigerator: Proposed Penalty (2013-CE-5355) More Documents & Publications

432

Condensation of refrigerants on vertical fluted tubes  

DOE Green Energy (OSTI)

Experiments were run to determine heat transfer performance of single vertical fluted tubes with selected fluids condensing on the outside. Working fluids included six fluorocarbons (Refrigerants 11, 21, 22, 113, 114, and 115) and a hydrocarbon (Refrigerant 600a or isobutane). The nine test tubes were of 2.54-cm (1-in.) nominal outside diameter and 1.2 m (4 ft) in length with from 0 (smooth) to 60 axial flutes. Condensing heat transfer coefficients ranged from 620 to 7900 W/m/sup 2/ . K (110 to 1400 Btu/hr . ft/sup 2/ . /sup 0/F) over the heat flux range of 2000 to 43,000 W/m/sup 2/ (920 to 13,600 Btu/hr . ft/sup 2/). All parameters are based on total condensing surface area. The data show that, for a given heat flux, a fluted tube can increase condensing coefficients up to 6.0 times smooth tube values. Further heat transfer enhancement was achieved by the use of drainage skirts on fluted tubes; these skirts effectively divided the 1.2-m (4-ft) tubes into two, four, and eight equal condensing lengths.

Combs, S.K.; Mailen, G.S.; Murphy, R.W.

1978-08-01T23:59:59.000Z

433

Simulation of the tropical Pacific climate with a coupled ocean - atmosphere general circulation model. Part II: Interannual variability  

Science Conference Proceedings (OSTI)

Two multiyear simulations with a coupled ocean-atmosphere general circulation model (GCM)-totaling 45 years-are used to investigate interannual variability at the equator. The model consists of the UCLA global atmospheric GCM coupled to the GFDL oceanic GCM, dynamically active over the tropical Pacific. Multichannel singular spectrum analysis along the equator identifies ENSO-like quasi-biennial (QB) and quasi-quadrennial (QQ) modes. Both consist of predominantly standing oscillations in sea surface temperature and zonal wind stress that peak in the central or east Pacific, accompanied by an oscillation in equatorial thermocline depth that is characterized by a phase shift of about 90{degrees} across the basin, with west leading east. Simulated interannual variability is weaker than observed in both simulations. One of these is dominated by the QB, the other by the QQ mode, although the two differ only in details of the surface-layer parameterizations. 42 refs., 19 figs., 2 tabs.

Robertson, A.W.; Ma, C.C.; Ghil, M. [Univ. of California, Los Angeles, CA (United States)] [and others

1995-05-01T23:59:59.000Z

434

Chaos, Quasiperiodicity, and Interannual Variability: Studies of a Stratospheric Vacillation Model  

Science Conference Proceedings (OSTI)

The parameter space of a stratospheric vacillation model is investigated numerically. The model is the quasigeostrophic ?-plane model introduced by Holton and Mass with time-independent forcing at the lower boundary. Chaotic and quasiperiodic ...

Bo Christiansen

2000-09-01T23:59:59.000Z

435

Indian Ocean variability in the CMIP5 multi-model ensemble: The basin mode  

Science Conference Proceedings (OSTI)

This study evaluates the simulation of the Indian Ocean Basin (IOB) mode and relevant physical processes in Coupled Model Intercomparison Projects phase 5 (CMIP5) models. Historical runs from 20 CMIP5 models are available for the analysis. They ...

Yan Du; Shang-Ping Xie; Ya-Li Yang; Xiao-Tong Zheng; Lin Liu; Gang Huang

436

Vegetation Dynamics Enhancing Long-Term Climate Variability Confirmed by Two Models  

Science Conference Proceedings (OSTI)

Two different coupled climate–vegetation models, the Community Climate Model version 3 coupled to the Integrated Biosphere Simulator (CCM3–IBIS) and the Laboratoire de Météorologie Dynamique’s climate model coupled to the Organizing Carbon and ...

Christine Delire; Nathalie de Noblet-Ducoudré; Adriana Sima; Isabelle Gouirand

2011-05-01T23:59:59.000Z

437

Employment Of Fuzzy Logic In Feature Diagrams To Model Variability In Software Families  

Science Conference Proceedings (OSTI)

The features of software family members may vary according to the needs of particular market segments or purposes. The assessment of what will be common and what will be variable feature may result from particular needs and market strategies. Further, ... Keywords: FODA feature diagrams, feature diagram tree, fuzzy representation, knowledge base, power plant description

Silva Robak; Andrzej Pieczy?ski

2003-08-01T23:59:59.000Z

438

High resolution simulation of the South Asian monsoon using a variable resolution global climate model  

E-Print Network (OSTI)

High resolution simulation of the South Asian monsoon using a variable resolution global climate understand regional aspects of the South Asian monsoon rainfall distribution and the interactions between monsoon circulation and precipitation. For this purpose, two sets of ten member realizations are produced

Hourdin, Chez Frédéric

439

Economic Impacts of Climate Variability in South Africa and Development of Resource Prediction Models  

Science Conference Proceedings (OSTI)

An analysis of food and water supplies and economic growth in South Africa leads to the realization that climate variability plays a major role. Summer rainfall in the period of 1980–99 is closely associated (variance = 48%) with year-to-year ...

Mark R. Jury

2002-01-01T23:59:59.000Z

440

A Qualitatively Realistic Low-Order Model of the Extratropical Low-Frequency Variability Built from Long Records of Potential Vorticity  

Science Conference Proceedings (OSTI)

A low-order deterministic qualitative model is formulated in order to simulate extratropical low-frequency variability. This deterministic model is based on a filtering of the potential vorticity equation on the 315-K isentrope and a projection ...

Eduardo Da Costa; Robert Vautard

1997-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

A New Absorption Cycle: The Single-Effect Regenerative Absoprtion Refrigeration Cycle  

E-Print Network (OSTI)

REGENERATIVE ABSORPTION REFRIGERATION CYCLE ABSTRACT A new absorption cycle , using heat as the energy

Dao, K.

2011-01-01T23:59:59.000Z

442

Evolution of the Standard Helium Liquefier and Refrigerator Range designed by Air Liquide DTA, France  

E-Print Network (OSTI)

Evolution of the Standard Helium Liquefier and Refrigerator Range designed by Air Liquide DTA, France

Crispel, S; Caillaud, A; Delcayre, F; Grabie, V

2008-01-01T23:59:59.000Z

443

Research of Refrigerant Phase-Change Stirling-Cycle Heat Engines  

Science Conference Proceedings (OSTI)

This paper firstly introduces the principles of Refrigerant Phase-Change Stirling-Cycle solar power towers This heat engines use solar reservoire. When the refrigerant in an engine cylinder absorbs heat from high-temperature heat sources, refrigerant ... Keywords: refrigerant phase-change cycle, heat engines, finite-time thermodynamics

Dezhong Huang; Fuer Wu

2011-01-01T23:59:59.000Z

444

Effect of parasitic refrigeration on the efficiency of magnetic liquefiers  

SciTech Connect

Our studies have shown that magnetic refrigerators have the potential to liquefy cryogens very efficiently. High efficiency is especially important for liquid hydrogen and natural gas applications where the liquefaction costs are a significant fraction of the total liquid cost. One of the characteristics of magnetic refrigerators is the requirement for a high-field superconducting magnet. Providing a 4.2-K bath for this magnet will require a small amount of parasitic refrigeration at 4.2 K even though the rest of the liquefier may be at 110 K (liquid natural gas) or higher. For several different refrigeration power levels at 4.2 K, we have calculated the efficiency of the magnetic liquefier as a function of power, temperature and the 4.2-K refrigerator efficiency. The results show that if the ratio of the thermal load at 4.2 K to the main refrigerator power is 0.001 or less, the effect on the efficiency of the liquefier is negligible at all temperatures below room temperature provided the 4.2-K refrigerator efficiency is high.

Barclay, J.A.; Stewart, W.F.

1982-01-01T23:59:59.000Z

445

The importance of climatological variability and the rate at which waste is added to modeling water budget of landfills  

SciTech Connect

A transient one-dimensional wetting front model was developed to predict water budgets for landfills. The model simulates the moisture profile by a series of blocks, each of which has a uniform soil moisture content. The model can simulate the continual stacking of waste by adding blocks, which represent new waste layers. The model can be programmed to build up a landfill at a given rate and to cap the landfill with a liner once a specific height has been reached. The wetting front model has been compared with models that solve the Richards Equation directly. In past studies the results between the two types of models compared well,but the wetting front model solved problems with a fraction of the computer time. Because of its efficient algorithms, the wetting front model is well suited for Monte Carlo simulation of different meteorological conditions in order to produce probability density functions for runoff, evapotranspiration, and leachate generation. In order to simulate different meteorological conditions, the TVA developed RGEN, which generates hourly rainfall, and EGEN which generates daily potential evaporation rates. The results of the numerous runs with the wetting front model were used to determine the potential importance of climatological variability and the effects of the rate at which new waste is added on the water budget of dry-stack fly ash landfills. 13 refs., 12 figs., 3 tabs.

Young, S.C.; Clapp, R.B.

1989-01-01T23:59:59.000Z

446

Evaluation of Model-generated Cloudiness: Satellite-observed and Model-generated Diurnal Variability of Brightness Temperature  

Science Conference Proceedings (OSTI)

In an attempt to validate the ECMWF model’s cloudiness, model output has been processed to reproduce satellite measurements as closely as possible. Brightness temperatures in the longwave window channel of Meteosat are simulated from cloudiness, ...

Jean-Jacques Morcrette

1991-05-01T23:59:59.000Z

447

Variability management of safety and reliability models: an intermediate model towards systematic reuse of component fault trees  

Science Conference Proceedings (OSTI)

Reuse of fault trees helps in reducing costs and effort when conducting Fault Tree Analyses (FTAs) for a set of similar systems. Some approaches have been proposed for the systematic reuse of fault trees along with the development of a product line of ... Keywords: component fault trees, fault tree analysis, product line engineering, safety and reliability, variability management

Carolina Gómez; Peter Liggesmeyer; Ariane Sutor

2010-09-01T23:59:59.000Z

448

Microcomputer Software for Refrigerant Property and Cycle Analysis Calculations  

E-Print Network (OSTI)

A microcomputer program entitled REFRIG has been developed to determine the thermodynamic properties of common refrigerants and to analyze vapor-compression refrigeration cycles. This paper describes the theoretical basis for property determination and for the cycle analysis. Validation of property calculations is discussed. A number of features are described which have been incorporated into the program to enhance its usefulness to the engineer in analyzing system performance. Two example cases are presented to illustrate the application of the program to problems in design and operation of refrigeration systems.

Bierschenk, J. L.; Strohl, S. T.; Schmidt, P. S.

1985-05-01T23:59:59.000Z

449

New Regenerative Cycle for Vapor Compression Refrigeration  

Office of Scientific and Technical Information (OSTI)

SCIENTIFIC REPORT SCIENTIFIC REPORT Title Page Project Title: New Regenerative Cycle for Vapor Compression Refrigeration DOE Award Number: DE-FG36-04GO14327 Document Title: Final Scientific Report Period Covered by Report: September 30, 2004 to September 30, 2005 Name and Address of Recipient Organization: Magnetic Development, Inc., 68 Winterhill Road, Madison, CT 06443, phone: 203-214-7247, fax: 203-421-7948, e-mail: mjb1000@aol.com Contact Information: Mark J. Bergander, Ph.D., P.E., Principal Investigator, phone: 203-214-7247, fax: 203-421-7948, e-mail: mjb1000@aol.com Project Objective (as stated in the proposal): The main objective of this project is to confirm on a well-instrumented prototype the theoretically derived claims of higher efficiency and coefficient

450

Bipolar pulse field for magnetic refrigeration  

DOE Patents (OSTI)

A magnetic refrigeration apparatus includes first and second steady state magnets, each having a field of substantially equal strength and opposite polarity, first and second bodies made of magnetocaloric material disposed respectively in the influence of the fields of the first and second steady state magnets, and a pulsed magnet, concentric with the first and second steady state magnets, and having a field which cycles between the fields of the first and second steady state magnets, thereby cyclically magnetizing and demagnetizing and thus heating and cooling the first and second bodies. Heat exchange apparatus of suitable design can be used to expose a working fluid to the first and second bodies of magnetocaloric material. A controller is provided to synchronize the flow of working fluid with the changing states of magnetization of the first and second bodies. 2 figs.

Lubell, M.S.

1994-10-25T23:59:59.000Z

451

Safety audit of refrigerated liquefied gas facilities  

SciTech Connect

An Exxon Research and Engineering Co. comprehensive review of engineering practices and application of safety requirements at Exxon's world-wide refrigerated liquefied hydrocarbon gas storage and handling installations, which included a field audit of about 90 tanks at 30 locations, showed that catastrophic tank failure was not a credible event with properly operated and maintained tanks designed, constructed, and tested in accordance with API Standard 620, Design and Construction of Large Welded Low-Pressure Storage Tanks, although supplemental requirements were suggested to further enhance safety. The review also showed that any meaningful safety audit should be comprehensive and must include all facilities with careful attention to detail. The review embraces products of -1 to -167C and included LNG, ethylene, LPG, and LPG olefins. Recent and proposed LNG safety legislation; some field audit results; and recommendations as to design, construction, and operation of LNG and LPG storage facilities, marine terminals, and tankers, are also discussed.

Feely, F.J.; Sommer, E.C.; Marshall, B.T.; Palmer, A.J.

1980-01-01T23:59:59.000Z

452

Evaluating Modeled Intra- to Multidecadal Climate Variability Using Running Mann–Whitney Z Statistics  

Science Conference Proceedings (OSTI)

An analysis method previously used to detect observed intra- to multidecadal (IMD) climate regimes was adapted to compare observed and modeled IMD climate variations. Pending the availability of the more appropriate phase 5 Coupled Model ...

Steven A. Mauget; Eugene C. Cordero; Patrick T. Brown

2012-03-01T23:59:59.000Z

453

Base-state Substitution: An Idealized Modeling Technique for Approximating Environmental Variability  

Science Conference Proceedings (OSTI)

Base-state substitution (BSS) is a novel modeling technique for approximating environmental heterogeneity in idealized simulations. After a certain amount of model run time, base-state substitution replaces the original horizontally homogeneous ...

Casey E. Letkewicz; Adam J. French; Matthew D. Parker

454

Modeling spatial variability of 137Cs surface activity in a mountain zone  

Science Conference Proceedings (OSTI)

Based on 137Cs surface activity field studies performed on a workshop zone, we succeeded in identifying the main criterion permitting surface activity modeling to be extended. Geomorphometric data derived from the Digital Elevation Model (slope, ...

J. M. Métivier; L. Pourcelot

2002-01-01T23:59:59.000Z

455

The Temporal Variability of Soil Moisture and Surface Hydrological Quantities in a Climate Model  

Science Conference Proceedings (OSTI)

The variance budget of land surface hydrological quantities is analyzed in the second Atmospheric Model Intercomparison Project (AMIP2) simulation made with the Canadian Centre for Climate Modelling and Analysis (CCCma) third-generation general ...

Vivek K. Arora; George J. Boer

2006-11-01T23:59:59.000Z

456

Global Modeling of Land Water and Energy Balances. Part III: Interannual Variability  

Science Conference Proceedings (OSTI)

The Land Dynamics (LaD) model is tested by comparison with observations of interannual variations in discharge from 44 large river basins for which relatively accurate time series of monthly precipitation (a primary model input) have recently ...

A. B. Shmakin; P. C. D. Milly; K. A. Dunne

2002-06-01T23:59:59.000Z

457

Multilevel Regression Modeling of Nonlinear Processes: Derivation and Applications to Climatic Variability  

Science Conference Proceedings (OSTI)

Predictive models are constructed to best describe an observed field’s statistics within a given class of nonlinear dynamics driven by a spatially coherent noise that is white in time. For linear dynamics, such inverse stochastic models are ...

S. Kravtsov; D. Kondrashov; M. Ghil

2005-11-01T23:59:59.000Z

458

Base-State Substitution: An Idealized Modeling Technique for Approximating Environmental Variability  

Science Conference Proceedings (OSTI)

Base-state substitution (BSS) is a novel modeling technique for approximating environmental heterogeneity in idealized simulations. After a certain amount of model run time, base-state substitution replaces the original horizontally homogeneous ...

Casey E. Letkewicz; Adam J. French; Matthew D. Parker

2013-09-01T23:59:59.000Z

459

Interannual Variability of Meridional Heat Transport in a Numerical Model of the Upper Equatorial Pacific ocean  

Science Conference Proceedings (OSTI)

The interannual heat budget of the Pacific equatorial upwelling zone is studied using a primitive equation, a reduced gravity model of the upper Pacific equatorial ocean. The model is forced with monthly mean FSU winds from 1971 to 1990. A ...

Esther C. Brady

1994-12-01T23:59:59.000Z

460

Variability and Coherence of the Agulhas Undercurrent in a High-Resolution Ocean General Circulation Model  

Science Conference Proceedings (OSTI)

The Agulhas Current system has been analyzed in a nested high-resolution ocean model and compared to observations. The model shows good performance in the western boundary current structure and the transports off the South African coast. This ...

A. Biastoch; L. M. Beal; J. R. E. Lutjeharms; T. G. D. Casal

2009-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Potential Predictability and AMIP Implications of Midlatitude Climate Variability in Two General Circulation Models  

Science Conference Proceedings (OSTI)

Ensembles of extended Atmospheric Model Intercomparison Project (AMIP) runs from the general circulation models of the National Centers for Environmental Prediction (formerly the National Meteorological Center) and the Max-Planck Institute (...

T. P. Barnett; K. Arpe; L. Bengtsson; M. Ji; A. Kumar

1997-09-01T23:59:59.000Z

462

Development of Refrigerant Change Indicator and Dirty Air Filter Sensor  

Science Conference Proceedings (OSTI)

The most common problems affecting residential and light commercial heating, ventilation, and air-conditioning (HVAC) systems are slow refrigerant leaks and dirty air filters. Equipment users are usually not aware of a problem until most of the refrigerant has escaped or the air filter is clogged with dirt. While a dirty air filter can be detected with a technology based on the air pressure differential across the filter, such as a ''whistling'' indicator, it is not easy to incorporate this technology into existing HVAC diagnostic equipment. Oak Ridge National Laboratory is developing a low-cost, nonintrusive refrigerant charge indicator and dirty air filter detection sensor. The sensors, based on temperature measurements, will be inexpensive and easy to incorporate into existing heat pumps and air conditioners. The refrigerant charge indicator is based on the fact that when refrigerant starts to leak, the evaporator coil temperature starts to drop and the level of liquid subcooling drops. When the coil temperature or liquid subcooling drops below a preset reading, a signal, such as a yellow warning light, can be activated to warn the equipment user that the system is undercharged. A further drop of coil temperature or liquid subcooling below another preset reading would trigger a second warning signal, such as a red warning light, to warn the equipment user that the unit now detects a leak and immediate action should be taken. The warning light cannot be turned off until it is re-set by a refrigeration repairman. To detect clogged air filters, two additional temperature sensors can be applied, one each across the evaporator. When the air filter is accumulating buildup, the temperature differential across the evaporator will increase because of the reduced airflow. When the temperature differential reaches a pre-set reading, a signal will be sent to the equipment user that the air filter needs to be changed. A traditional refrigerant charge indicator requires intrusion into the system to measure the refrigerant high-side and low-side pressures. Once the pressures are known, based on the equipment's refrigerant charging chart? or in most cases, based on the technician's experience? the refrigerant charging status is determined. However, there is a catch: by the time a refrigeration technician is called, most of the refrigerant has already escaped into the atmosphere. The new technology provides a real-time warning so that when, say, 20% of the refrigerant has leaked, the equipment users will be warned, even though the equipment is still functioning properly at rated capacity. Temperature sensors are becoming very accurate and very low in cost, compared with pressure sensors. Using temperature sensors to detect refrigerant charge status is inherently nonintrusive, inexpensive, and accurate. With the addition of two temperature sensors for detecting dirty air filters, the capability of the diagnostic equipment is further enhanced with very little added cost. This report provides laboratory test data on the change of indoor coil refrigerant temperature and subcooling as a function of refrigerant charge for a 2-ton split heat pump system. The data can be used in designing the indicators for refrigerant loss and dirty air filter sensors.

Mei, V.

2003-06-24T23:59:59.000Z

463

Effect of Atlantic Meridional Overturning Circulation on Tropical Atlantic Variability: A Regional Coupled Model Study  

Science Conference Proceedings (OSTI)

A simplified coupled ocean–atmosphere model, where an atmospheric general circulation model (AGCM) is fully coupled to a 2½-layer reduced-gravity ocean model (RGO) over the tropical Atlantic basin, is presented in the context of studying the role ...

Caihong Wen; Ping Chang; Ramalingam Saravanan

2011-07-01T23:59:59.000Z

464

Variational Data Assimilation with a Variable Resolution Finite-Element shallow-water Equations Model  

Science Conference Proceedings (OSTI)

The adjoint model of a finite-element shallow-water equations model was obtained with a view to calculate the gradient of a cost functional in the framework of using this model to carry out variational data assimilation (VDA) experiments using ...

Keyun Zhu; I. Michael Navon; Xiaolei Zou

1994-05-01T23:59:59.000Z

465

Property:Building/SPElectrtyUsePercRefrigeration | Open Energy Information  

Open Energy Info (EERE)

SPElectrtyUsePercRefrigeration SPElectrtyUsePercRefrigeration Jump to: navigation, search This is a property of type String. Refrigeration Pages using the property "Building/SPElectrtyUsePercRefrigeration" Showing 25 pages using this property. (previous 25) (next 25) S Sweden Building 05K0001 + 0.0 + Sweden Building 05K0002 + 0.0 + Sweden Building 05K0003 + 0.0 + Sweden Building 05K0004 + 0.0 + Sweden Building 05K0005 + 0.0 + Sweden Building 05K0006 + 4.24846345193 + Sweden Building 05K0007 + 0.0 + Sweden Building 05K0008 + 0.0 + Sweden Building 05K0009 + 0.0 + Sweden Building 05K0010 + 24.6944086225 + Sweden Building 05K0011 + 0.0 + Sweden Building 05K0012 + 0.0 + Sweden Building 05K0013 + 1.29913989581 + Sweden Building 05K0014 + 7.46645043826 + Sweden Building 05K0015 + 0.0 +

466

DOE Reaches Agreement with LG Electronics, USA, On Refrigerator Energy  

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

Reaches Agreement with LG Electronics, USA, On Refrigerator Reaches Agreement with LG Electronics, USA, On Refrigerator Energy Matter DOE Reaches Agreement with LG Electronics, USA, On Refrigerator Energy Matter November 14, 2008 - 4:47pm Addthis ENERGY STAR® Program Continues to Help American Consumers Make Energy Efficient Choices WASHINGTON - The U.S. Department of Energy (DOE) today announced an agreement with LG Electronics, USA, Inc. (LG), resolving concerns related to energy usage measurements reported on LG French Door refrigerators with through-the-door ice and water service. The ENERGY STAR® program helps American consumers make energy efficient choices, saving billions of dollars while protecting the environment by using identified energy efficient products and practices. "DOE believes that the actions LG plans to take will benefit consumers and

467

Computer program for determining the thermodynamic properties of Freon refrigerants  

DOE Green Energy (OSTI)

This program was written to be used as a subroutine. The program determines the thermodynamics of Freon refrigerants. The following refrigerants can be analyzed F-11, F-12, F-13, F-14, F-21, F-22, F-23, F-113, and F-114. The subroutine can evaluate a thermodynamic state for these refrigerants given any of the following pairs of state quantities: pressure and quality, pressure and entropy, pressure and enthalpy, temperature and quality, temperature and specific volume, and temperature and pressure. These six pairs of knowns allow the user to analyze any thermodynamic cycle utilizing a refrigerant as the working fluid. The Downing form of the Martin equation of state was used. This report contains a brief description, flow chart and listing of all subroutines required.

Riemer, D.H.; Jacobs, H.R.; Boehm, R.F.

1977-12-01T23:59:59.000Z

468

Computer program for determining the thermodynamic properties of freon refrigerants  

DOE Green Energy (OSTI)

This program was written to be used as a subroutine. The program determines the thermodynamics of Freon refrigerants. The following refrigerants can be analyzed F-11, F-12, F-13, F-14, F-21, F-22, F-23, F-113, and F-114. The subroutine can evaluate a thermodynamic state for these refrigerants given any of the following pairs of state quantities: pressure and quality, pressure and entropy, pressure and enthalpy, temperature and quality, temperature and specific volume and temperature and pressure. These six pairs of knowns allow the user to analyze any thermodynamic cycle utilizing a refrigerant as the working fluid. The Downing form of the Martin equation of state was used. A brief description, flow chart, and listing of all subroutines required are presented.

Riemer, D.H.; Jacobs, H.R.; Boehm, R.F.

1976-07-01T23:59:59.000Z

469

Product Standards for Refrigerators (Japan) | Open Energy Information  

Open Energy Info (EERE)

Product Standards for Refrigerators (Japan) Product Standards for Refrigerators (Japan) Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Product Standards for Refrigerators (Japan) Focus Area: Appliances & Equipment Topics: Policy Impacts Website: www.eccj.or.jp/top_runner/pdf/tr_re-freez_Jul.2006.pdf Equivalent URI: cleanenergysolutions.org/content/product-standards-refrigerators-japan Language: English Policies: "Deployment Programs,Regulations" is not in the list of possible values (Deployment Programs, Financial Incentives, Regulations) for this property. DeploymentPrograms: Industry Codes & Standards Regulations: Appliance & Equipment Standards and Required Labeling This Energy Conservation Center Japan (ECCJ) document was created as a guide in response to its newly established set of standards and labelling

470

Energy Department Announces More Stringent Criteria for ENERGY STAR® Refrigerators  

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

WASHINGTON, DC - The U.S. Department of Energy (DOE) today announced increased energy efficient criteria for refrigerators carrying the ENERGY STAR® label.  In order to qualify, full-size...

471

Commercial Refrigerator Door: Proposed Penalty (2013-CE-5351)  

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

DOE alleged in a Notice of Proposed Civil Penalty that Commercial Refrigerator Door Company, Inc. failed to certify a variety of walk-in cooler or freezer components as compliant with the applicable energy conservation standards.

472

Energy Consumption of Refrigerators in Ghana - Outcomes of Household...  

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

Energy Consumption of Refrigerators in Ghana - Outcomes of Household Surveys Speaker(s): Essel Ben Hagan Date: July 12, 2007 - 12:00pm Location: 90-3122 Seminar HostPoint of...

473

Advanced refrigeration system for the Brookhaven superconducting cable project  

SciTech Connect

A description is given of a basic supercritical refrigerator. The present status of the cable enclosure and the types of cooling schemes being considered are presented with some examples of laboratory results and computer analysis. (MOW)

Jensen, J.E.

1975-01-01T23:59:59.000Z

474

Application of Cryocoolers to a Vintage Dilution Refrigerator  

SciTech Connect

A dilution refrigerator is required for 50mK detector operation of CDMS (Cryogenic Dark Matter Search). Besides shielding the dilution refrigerator itself, the liquid nitrogen shield and liquid helium bath in the refrigerator cool the detector cryostat heat shields and cool electronics, resulting in significant external heat loads at 80K and at 4K. An Oxford Instruments Kelvinox 400 has served this role for ten years but required daily transfers of liquid nitrogen and liquid helium. Complicating the cryogen supply is the location 800 meters below ground in an RF shielded, class 10000 clean room at Soudan, MN. Nitrogen and helium re-liquefiers using cryocoolers were installed outside the clean room and continuously condense room temperature gas and return the liquids to the dilution refrigerator through a transfer line. This paper will describe the design, installation, controls and performance of liquefaction systems.

Schmitt, Richard; Smith, Gary; Ruschman, Mark; /Fermilab; Beaty, Jim; /Minnesota U.

2011-06-06T23:59:59.000Z

475

Removing Odors from Refrigerators and Freezers after Food has Spoiled  

E-Print Network (OSTI)

If food has spoiled in a refrigerator or freezer because of a power outage or some other reason, undesirable odors can result. This publication explains how to eliminate odors from these appliances.

FCS Project Team - FDRM UNIT

2005-09-30T23:59:59.000Z

476

Three-dimensional model for multi-component reactive transport with variable density groundwater flow  

Science Conference Proceedings (OSTI)

PHWAT is a new model that couples a geochemical reaction model (PHREEQC-2) with a density-dependent groundwater flow and solute transport model (SEAWAT) using the split-operator approach. PHWAT was developed to simulate multi-component reactive transport ... Keywords: Cation exchange, Coastal groundwater flow and chemical transport/reaction, Density-dependent flow, MODFLOW, MT3DMS, PHREEQC-2, PHWAT, SEAWAT, Seawater intrusion, Snow-plough effect

X. Mao; H. Prommer; D. A. Barry; C. D. Langevin; B. Panteleit; L. Li

2006-05-01T23:59:59.000Z

477

Development and Validation of WECC Variable Speed Wind Turbine Dynamic Models for Grid Integration Studies  

DOE Green Energy (OSTI)

This paper describes reduced-order, simplified wind turbine models for analyzing the stability impact of large arrays of wind turbines with a single point of network interconnection.

Behnke, M.; Ellis, A.; Kazachkov, Y.; McCoy, T.; Muljadi, E.; Price, W.; Sanchez-Gasca, J.

2007-09-01T23:59:59.000Z

478

ResPoNSe: modeling the wide variability of residential energy consumption.  

E-Print Network (OSTI)

affect appliance energy consumption. For example, differentStates, 2005 Residential Energy Consumption Survey: HousingModeling of End-Use Energy Consumption in the Residential

Peffer, Therese; Burke, William; Auslander, David

2010-01-01T23:59:59.000Z

479

Model-based estimation of time-varying parameters and state variables in aerobic bioprocesses  

Science Conference Proceedings (OSTI)

Keywords: adaptive observer, aerobic bioprocess, biomass concentration, biomass growth rate, model-based estimation, observer stability, oxygen comsumption, time-varying parameters, yield coefficient

V. Lubenova

2000-08-01T23:59:59.000Z

480

ARI delegation to Japan on Alternative Refrigerants. [Foreign Trip Report  

SciTech Connect

Researchers from ARI member companies spoke at the International Conference on Alternative Refrigerants in Tokyo and visited several Japanese organizations for the purpose of exchanging information on alternative refrigerants. The specific purpose of the meetings was to review the methods being utilized to screen alternatives to CFCs and HCFCs: materials compatibility screening methods, lubricant testing techniques, as well as flammability studies. A list of papers presented at the conference is included.

Not Available

1993-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling variable refrigerant" 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

Hybrid refrigeration/sorption solar-cooling systems  

DOE Green Energy (OSTI)

The hybrid refrigeration/sorption concept is a technically feasible approach to solar cooling which has not yet been systematically evaluated. Various system configurations are possible, each with advantages and disadvantages relative to the others, and with respect to solar cooling systems based on the individual absorption, Rankine, and desiccant technologies. Conventional cooling and dehumidification, sorption dehumidification, and the effects on the refrigeration unit of adding a dehumidifier are discussed.

Curran, H.M.

1981-08-01T23:59:59.000Z

482

Transport Refrigeration Equipment: Analysis of Emissions and Economics of Electrification  

Science Conference Proceedings (OSTI)

Most refrigerated trucks, trailers, and ocean containers used to transport, deliver, and store fresh and frozen foods utilize an auxiliary diesel engine (10 to 34 hp) to operate on-board refrigeration systems. These engines are vital for product temperature control while the vehicle is on the road, but also idle while the truck is parked at a facility, pre-cooling, loading, unloading, or waiting to be dispatched. As a result, large distribution centers can experience high concentrations of pollutants and...

2004-06-30T23:59:59.000Z

483

Compatibility of refrigerants and lubricants with engineering plastics  

Science Conference Proceedings (OSTI)

All seven oil immersion studies are complete at both temperatures. Nine out of ten refrigerant ambient immersion studies are complete including 60C (140F) for R-123. All 22 plastic test materials have been molded into test bars. All test bars have been quality controlled for physical consistency and integrity. All 22 test chambers are functional. Creep loads have been increased to 25% of ultimate tensile. Refrigerant has solubilities of Emery 2927 with R-22 and 134a are complete.

Cavestri, R.C.

1992-07-01T23:59:59.000Z

484

Properties and Cycle Performance of Refrigerant Blends Operating Near and Above the Refrigerant Critical Point, Task 2: Air Conditioner System Study  

SciTech Connect

The main goal of this project was to investigate and compare the performance of an R410A air conditioner to that of an R22 air conditioner, with specific interest in performance at high ambient temperatures at which the condenser of the R410A system may be operating above the refrigerant's critical point. Part 1 of this project consisted of conducting comprehensive measurements of thermophysical for refrigerant R125 and refrigerant blends R410A and R507A and developing new equation of state formulations and mixture models for predicting thermophysical properties of HFC refrigerant blends. Part 2 of this project conducted performance measurements of split-system, 3-ton R22 and R410A residential air conditioners in the 80 to 135 F (27.8 to 57.2 C) outdoor temperature range and development of a system performance model. The performance data was used in preparing a beta version of EVAP-COND, a windows-based simulation package for predicting performance of finned-tube evaporators and condensers. The modeling portion of this project also included the formulation of a model for an air-conditioner equipped with a thermal expansion valve (TXV). Capacity and energy efficiency ratio (EER) were measured and compared. The R22 system's performance was measured over the outdoor ambient temperature range of 80 to 135 F (27.8 to 57.2 C). The same test range was planned for the R410A system. However, the compressor's safety system cut off the compressor at the 135.0 F (57.2 C) test temperature. The highest measurement on this system was at 130.0 F (54.4 C). Subsequently, a custom-manufactured R410A compressor with a disabled safety system and a more powerful motor was installed and performance was measured at outdoor temperatures up to 155.0 F (68.3 C). Both systems had similar capacity and EER performance at 82.0 F (27.8 C). The capacity and EER degradation of both systems were nearly linearly dependent with rising ambient outdoor ambient test temperatures. The performance degradation of R410A at higher temperatures was greater than R22. However, the R22 and R410A systems both operated normally during all tests. Visual observations of the R410A system provided no indication of vibrations or TXV hunting at high ambient outdoor test conditions with the compressor operating in the transcritical regime.

Piotr A. Domanski; W. Vance Payne

2002-10-31T23:59:59.000Z

485

Properties and Cycle Performance of Refrigerant Blends Operating Near and Above the Refrigerant Critical Point, Task 2: Air Conditioner System Study  

SciTech Connect

The main goal of this project was to investigate and compare the performance of an R410A air conditioner to that of an R22 air conditioner, with specific interest in performance at high ambient temperatures at which the condenser of the R410A system may be operating above the refrigerant's critical point. Part 1 of this project consisted of conducting comprehensive measurements of thermophysical for refrigerant R125 and refrigerant blends R410A and R507A and developing new equation of state formulations and mixture models for predicting thermophysical properties of HFC refrigerant blends. Part 2 of this project conducted performance measurements of split-system, 3-ton R22 and R410A residential air conditioners in the 80 to 135 F (27.8 to 57.2 C) outdoor temperature range and development of a system performance model. The performance data was used in preparing a beta version of EVAP-COND, a windows-based simulation package for predicting performance of finned-tube evaporators and condensers. The modeling portion of this project also included the formulation of a model for an air-conditioner equipped with a thermal expansion valve (TXV). Capacity and energy efficiency ratio (EER) were measured and compared. The R22 system's performance was measured over the outdoor ambient temperature range of 80 to 135 F (27.8 to 57.2 C). The same test range was planned for the R410A system. However, the compressor's safety system cut off the compressor at the 135.0 F (57.2 C) test temperature. The highest measurement on this system was at 130.0 F (54.4 C). Subsequently, a custom-manufactured R410A compressor with a disabled safety system and a more powerful motor was installed and performance was measured at outdoor temperatures up to 155.0 F (68.3 C). Both systems had similar capacity and EER performance at 82.0 F (27.8 C). The capacity and EER degradation of both systems were nearly linearly dependent with rising ambient outdoor ambient test temperatures. The performance degradation of R410A at higher temperatures was greater than R22. However, the R22 and R410A systems both operated normally during all tests. Visual observations of the R410A system provided no indication of vibrations or TXV hunting at high ambient outdoor test conditions with the compressor operating in the transcritical regime.

Piotr A. Domanski; W. Vance Payne

2002-10-31T23:59:59.000Z

486

Variability in a Mixed Layer Ocean Model Driven by Stochastic Atmospheric Forcing  

Science Conference Proceedings (OSTI)

A stochastic model of atmospheric surface conditions, developed from 30 years of data at Ocean Weather Station P in the northeast Pacific, is used to drive a mixed layer model of the upper mean. The spectral characteristics of anomalies in the ...

Michael A. Alexander; Cecile Penland

1996-10-01T23:59:59.000Z

487

Internal Variability of an Energy-Balance Model with Delayed Albedo Effects  

Science Conference Proceedings (OSTI)

We present a simple, deterministic energy-balance model with possible relevance to climatic variations on the time scale of glaciation cycles. The lag between ice-sheet extent and zonally-averaged temperature is modeled as a time delay in the ice-...

K. Bhattacharya; M. Ghil; I. L. Vulis

1982-08-01T23:59:59.000Z

488

Transition to Aperiodic Variability in a Wind-Driven Double-Gyre Circulation Model  

Science Conference Proceedings (OSTI)

Multiple equilibria as well as periodic and aperiodic solution regimes are obtained in a barotropic model of the midlatitude ocean’s double-gyre circulation. The model circulation is driven by a steady zonal wind profile that is symmetric with ...

Kyung-Il Chang; Michael Ghil; Kayo Ide; Chung-Chieng Aaron Lai

2001-05-01T23:59:59.000Z

489

Refrigerator Efficiency in Ghana: Tailoring an appliance markettransformation program design for Africa  

SciTech Connect

A simple replication of developed country applianceefficiency labels and standards is unlikely to be feasible in Ghana andmany other countries in Africa. Yet by creatively modifying the developedcountry appliance efficiency market transformation model, it should bepossible to achieve dramatic energy use reductions. As was true indeveloped countries in the previous two decades, refrigeration efficiencyimprovements provide the greatest energy savings potential in theresidential electricity sector in Ghana. Although Ghana, like manyAfrican countries may impose standards on imports since Ghana does nothave manufacturing facilities for appliances in country. This approachmay hurt some consumers who patronize a very diverse market of usedappliances imported from Europe. We discuss how meeting the challenges ofthe Ghanaian market will require modification of the usual energyefficiency labeling and standards paradigm. But once a refrigeratormarket transformation is accomplished in Ghana, we estimate an averageenergy savings potential of 550 kWh/refrigerator/year, and a monetarysavings of more than $35/refrigerator/year. We discuss how this modifiedrefrigerator efficiency market transformation may occur in the Ghanaiancontext. If successful, this market transformation is likely to be anexample for many other African countries.

Ben Hagan, Essel; Van Buskirk, Robert; Ofosu-Ahenkorah, Alfred; McNeil, Michael A.

2006-02-28T23:59:59.000Z

490

Fridge of the future: Designing a one-kilowatt-hour/day domestic refrigerator-freezer  

SciTech Connect

An industry/government Cooperative Research and Development Agreement (CRADA) was established to evaluate and test design concepts for a domestic refrigerator-freezer unit that represents approximately 60% of the US market. The goal of the CRADA was to demonstrate advanced technologies which reduce, by 50 percent, the 1993 NAECA standard energy consumption for a 20 ft{sup 3} (570 I) top-mount, automatic-defrost, refrigerator-freezer. For a unit this size, the goal translated to an energy consumption of 1.003 kWh/d. The general objective of the research was to facilitate the introduction of cost-efficient technologies by demonstrating design changes that can be effectively incorporated into new products. A 1996 model refrigerator-freezer was selected as the baseline unit for testing. Since the unit was required to meet the 1993 NAECA standards, the energy consumption was quite low (1.676 kWh/d), thus making further reductions in energy consumption very challenging. Among the energy saving features incorporated into the original design of the baseline unit were a low-wattage evaporator fan, increased insulation thicknesses, and liquid line flange heaters.

Vineyard, E.A.; Sand, J.R.

1998-03-01T23:59:59.000Z

491

Heat exchanger bypass system for an absorption refrigeration system  

DOE Patents (OSTI)

A heat exchanger bypass system for an absorption refrigeration sys