skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: User's guide for numerical modeling of buoyant plumes in a turbulent, stratified atmosphere

Abstract

A widely applicable computational model of buoyant, bent-over plumes in realistic atmospheres is constructed. To do this, the two-dimensional, time-dependent fluid mechanics equations are numerically integrated, while a number of important physical approximations serve to keep the approach at a tractable level. A three-dimensional picture of a steady state plume is constructed from a sequence of time-dependent, two-dimensional plume cross sections--each cross section of the sequence is spaced progressively further downwind as it is advected for a progressively longer time by the prevailing wind. The dynamics of the plume simulations are quite general. The buoyancy sources in the plume include the sensible heat in the plume, the latent heat absorbed or released in plume moisture processes, and the heating of the plume by a radioactive pollutant in the plume. The atmospheric state in the simulations is also quite general. Atmospheric variables are allowed to be functions of height, and the ambient atmospheric turbulence (also a function of height) is included in the simulations.

Authors:
;
Publication Date:
Research Org.:
Massachusetts Inst. of Tech., Cambridge (USA). Energy Lab.
OSTI Identifier:
5009150
Alternate Identifier(s):
OSTI ID: 5009150
Report Number(s):
PB-80-114549
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; AIR POLLUTION; PLUMES; MATHEMATICAL MODELS; RADIOACTIVE AEROSOLS; COMPUTER CODES; TURBULENCE; AEROSOLS; COLLOIDS; DISPERSIONS; POLLUTION; SOLS 500300* -- Environment, Atmospheric-- Radioactive Materials Monitoring & Transport-- (-1989); 500200 -- Environment, Atmospheric-- Chemicals Monitoring & Transport-- (-1989)

Citation Formats

Bennett, R.G., and Golay, M.W.. User's guide for numerical modeling of buoyant plumes in a turbulent, stratified atmosphere. United States: N. p., 1979. Web.
Bennett, R.G., & Golay, M.W.. User's guide for numerical modeling of buoyant plumes in a turbulent, stratified atmosphere. United States.
Bennett, R.G., and Golay, M.W.. Thu . "User's guide for numerical modeling of buoyant plumes in a turbulent, stratified atmosphere". United States. doi:.
@article{osti_5009150,
title = {User's guide for numerical modeling of buoyant plumes in a turbulent, stratified atmosphere},
author = {Bennett, R.G. and Golay, M.W.},
abstractNote = {A widely applicable computational model of buoyant, bent-over plumes in realistic atmospheres is constructed. To do this, the two-dimensional, time-dependent fluid mechanics equations are numerically integrated, while a number of important physical approximations serve to keep the approach at a tractable level. A three-dimensional picture of a steady state plume is constructed from a sequence of time-dependent, two-dimensional plume cross sections--each cross section of the sequence is spaced progressively further downwind as it is advected for a progressively longer time by the prevailing wind. The dynamics of the plume simulations are quite general. The buoyancy sources in the plume include the sensible heat in the plume, the latent heat absorbed or released in plume moisture processes, and the heating of the plume by a radioactive pollutant in the plume. The atmospheric state in the simulations is also quite general. Atmospheric variables are allowed to be functions of height, and the ambient atmospheric turbulence (also a function of height) is included in the simulations.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Feb 01 00:00:00 EST 1979},
month = {Thu Feb 01 00:00:00 EST 1979}
}

Technical Report:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that may hold this item. Keep in mind that many technical reports are not cataloged in WorldCat.

Save / Share:
  • A set of equations describing the behavior of atmospheric plumes is derived in which special attention is given to the modeling of the microphysical processes and the treatment of the turbulence. An original numerical scheme for solving these equations is studied, and a FORTRAN IV computer code is discussed. Simulations using real atmospheric data are compared with onsite plume measurements. The model is found to accurately predict the flow characteristics of the plumes and the dispersal of water vapor in the most complex atmospheres.
  • A widely applicable computational model of buoyant moist plumes in turbulent atmospheres has been constructed. To achieve this a one dimensional Planetary Boundary Layer (P.B.L.) model has been developed to account for atmospheric turbulence while the two dimensional time dependent fluid mechanics equations which govern plume behavior are numerically integrated. A cloud microphysics model has been incorporated into the basic numerical code to account properly for the water content of the plume. The overall dynamics of the plume is quite general. The buoyancy source in the plume includes both the sensible heat and the latent heat absorbed or released inmore » the plume. The turbulence of the plume accounts for buoyancy generated or destroyed turbulence and a universal k-epsilon model has been set up along with the k-sigma model. The model is validated against complex field cases to demonstrate its ability to reproduce solutions to problems that are known. Comparisons to visible plume data show that both the dynamics of the plume are calculated with an acceptable accuracy. Comparisons with 'conventional' entrainment model show that the model can simulate plumes better since it takes into account more physical phenomena.« less
  • NEC-3 is a version of the Numerical Electromagnetics Code - Method of Moments that has been extended to model wires that are buried or penetrate the ground-air interface. Fields in the presence of an interface are obtained by interpolation or least-squares approximation using tables generated by an auxiliary program SOMNTX which evaluates Sommerfeld integrals. Asymptotic approximations for the field are used at larger distances. This approach is similar to that used in NEC-2 for wires above the interface, but now includes reflected field below the interface and field transmitted across the interface. NEC-3 retains all of the capabilities of NEC-2,more » and input data for NEC-2 should run with NEC-3 without change. NEC-3 requires about 14 percent more computer memory than NEC-2, however, so it may be worthwhile to retain a copy of NEC-2 for models not involving buried wires. This manual supplements the NEC-2 Users Guide and covers new features of NEC-3 and modifications to old options. The capabilities of NEC-3 and considerations for modeling buried wires are discussed. One new data card (UM) has been added and some options have been changed for other cards. Use of the program SOMNTX to generate the Sommerfeld integral tables for NEC-3 is discussed, followed by examples of modeling an antenna on a ground stake and a buried ground screen.« less
  • The HGSYSTEM/UF{sub 6} model was developed for use in preparing Safety Analysis Reports (SARs) by estimating the consequences of possible accidental releases of UF{sub 6} to the atmosphere at the gaseous diffusion plants (GDPs) located in Portsmouth, Ohio, and Paducah, Kentucky. Although the latter report carries a 1996 date, the work that is described was completed in late 1994. When that report was written, the primary release scenarios of interest were thought to be gas pipeline and liquid tank ruptures over open terrain away from the influence of buildings. However, upon further analysis of possible release scenarios, the developers ofmore » the SARs decided it was necessary to also consider accidental releases within buildings. Consequently, during the fall and winter of 1995-96, modules were added to HGSYSTEM/UF{sub 6} to account for flow and dispersion around buildings. The original HGSYSTEM/UF{sub 6} model also contained a preliminary method for accounting for the possible lift-off of ground-based buoyant plumes. An improved model and a new set of wind tunnel data for buoyant plumes trapped in building recirculation cavities have become available that appear to be useful for revising the lift-off algorithm and modifying it for use in recirculation cavities. This improved lift-off model has been incorporated in the updated modules for dispersion around buildings.« less