Assessment and Computerized Modeling of the Environmental Deposition of Military Smokes: Analysis of Meteorological Data from the AMADEUS Smoke Dispersion Experiments

Assessment and Computerized Modeling of the Environmental Deposition of Military Smokes: Analysis of Meteorological Data from the AMADEUS Smoke Dispersion Experiments PDF Author: D. F. Brown
Publisher:
ISBN:
Category :
Languages : en
Pages : 142

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Book Description
This report summarizes the meteorological data collected as part of the AMADEUS dispersion experiments. In addition, a preliminary analysis of these data was carried out. Averages of the surface-station and micrometeorological measurements were computed for each of 12 smoke release periods. Also, the stability of the atmosphere during these tests was characterized by analyzing (1) the standard deviation of the horizontal wind direction; (2) the bulk Richardson number; (3) the vertical profiles of wind and atmospheric temperature; and (4) direct measurements of the vertical heat and momentum fluxes. For four of the five daytime releases, the height of the boundary layer was determined from instrumented balloon soundings. Results show that the meteorological data are complete and consistent, both internally and with other studies of the atmospheric boundary level. The daytime convective conditions reveal a high degree of coherency, whereas the nighttime stable conditions are more spatially heterogeneous and less coherent. The stable boundary layer is generally less well understood than is the convective boundary layer, especially in a complex terrain setting. The data appear to offer significant potential for improving the state of dispersion modeling in this important area.

Assessment and Computerized Modeling of the Environmental Deposition of Military Smokes: Analysis of Meteorological Data from the AMADEUS Smoke Dispersion Experiments

Assessment and Computerized Modeling of the Environmental Deposition of Military Smokes: Analysis of Meteorological Data from the AMADEUS Smoke Dispersion Experiments PDF Author: D. F. Brown
Publisher:
ISBN:
Category :
Languages : en
Pages : 142

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Book Description
This report summarizes the meteorological data collected as part of the AMADEUS dispersion experiments. In addition, a preliminary analysis of these data was carried out. Averages of the surface-station and micrometeorological measurements were computed for each of 12 smoke release periods. Also, the stability of the atmosphere during these tests was characterized by analyzing (1) the standard deviation of the horizontal wind direction; (2) the bulk Richardson number; (3) the vertical profiles of wind and atmospheric temperature; and (4) direct measurements of the vertical heat and momentum fluxes. For four of the five daytime releases, the height of the boundary layer was determined from instrumented balloon soundings. Results show that the meteorological data are complete and consistent, both internally and with other studies of the atmospheric boundary level. The daytime convective conditions reveal a high degree of coherency, whereas the nighttime stable conditions are more spatially heterogeneous and less coherent. The stable boundary layer is generally less well understood than is the convective boundary layer, especially in a complex terrain setting. The data appear to offer significant potential for improving the state of dispersion modeling in this important area.

Assessment and Computerized Modeling of the Environmental Deposition of Military Smokes. Characterization of the Atmospheric Boundary Layer in Complex Terrain and Results from the Amadeus Smoke Dispersion Experiments

Assessment and Computerized Modeling of the Environmental Deposition of Military Smokes. Characterization of the Atmospheric Boundary Layer in Complex Terrain and Results from the Amadeus Smoke Dispersion Experiments PDF Author: D. F. Brown
Publisher:
ISBN:
Category :
Languages : en
Pages : 176

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Book Description
This report summarizes our analysis of the AMADEUS meteorological data Preliminary analysis (also given in Brown et al. 1990) of these data for each of the smoke-release periods include: (1) computation of averages of the surface-station and micrometeorological measurements (wind speed, wind direction, temperature), (2) stability characterization by analysis of bulk Richardson numbers and wind direction standard deviations, (3) examination of vertical heat and momentum fluxes from sonic-anemometer data, (4) analysis of spectra computed using 1-Hz micrometeorological data and (5) determination of boundary-layer height from the instrumented balloon soundings. Additional results given in this report include: (1) an analysis of vertical wind profiles, (2) comparisons of Meadowbrook data to similarity-based empirical relations and (3) a comprehensive analysis of the noctumal down-slope flows. The results show that the meteorological data are consistent, both internally and with other studies of the atmospheric boundary layer. The daytime convective conditions reveal a high degree of coherency, whereas the nighttime stable conditions are more spatially heterogeneous and less coherent. Analysis of surface-station data has shown that the characteristics of the nocturnal downslope flows in the Meadowbrook valleys are influenced by a combination of local cooling, local surface conditions and mesoscale drainage flows external to the Meadowbrook system. These data appear to offer significant potential for improving the state of dispersion modeling in this important area. RA 3, smoke, screening smoke, obscuring smoke, hexachloroethane, gas chromatography.

Assessment and Computerized Modeling of the Environmental Deposition of Military Smokes

Assessment and Computerized Modeling of the Environmental Deposition of Military Smokes PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 443

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Book Description
This report presents the average and instantaneous concentration measurements from a series of atmospheric dispersion experiments conducted under both stable and unstable atmospheric conditions. The experiments were undertaken at two different sites over both flat and complex terrain. Fog oil and hexachloroethane (HC) chemical smoke were the surface-level point aerosols used in these experiments. Depending on the site and atmospheric conditions, measurements of concentration at points along crosswind transects were taken over time periods of an hour at distances from 25m to 3000m from the source. These measurements included both aerosol photometer records for instantaneous concentration data and aspirated filter cassettes for average concentration data. The data taken in these tests compare well with developed models for both the mean and variance in concentration. Intermittency is important at all locations, with positive concentrations recorded in the mean plume centerline only 20% to 50% of the time. Concentration fluctuation intensity ranges from 2 near the plume centerline to over 20 at the plume edge. Point histograms are shown to agree with the exponential distribution for c>O. Spectra for the concentration data show an inertial-convective subrange with a 5/3-power law versus frequency behavior. Integral time scales at individual points are relatively constant within tests and are equal to the mean duration of episodes or bursts with c>O. The probability distribution of individual burst durations at each sampler shows an exponential distribution.

Field Measurement and Model Evaluation Program for Assessment of the Environmental Effects of Military Smokes: Evaluation of Atmospheric Wind Field and Dispersion Models for Fog-Oil Smoke Dispersion in Complex Terrain

Field Measurement and Model Evaluation Program for Assessment of the Environmental Effects of Military Smokes: Evaluation of Atmospheric Wind Field and Dispersion Models for Fog-Oil Smoke Dispersion in Complex Terrain PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 114

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Book Description
Three models used to predict the wind field and pollutant dispersion in complex terrain are compared with smoke dispersion data acquired as part of the AMADEUS field experiments in 1987 near Red Bluff, California. The models evaluated were WADOCT, HOTMAC/RAPTAD, and RAMS. The data base for model testing encompassed 7 fog-oil smoke releases from ground level under stable meteorological conditions. Smoke concentrations were measured out to 4 km downwind. Time-dependent meteorological and source data were available from these tests to be used as model input. The results showed that the WADOCT model predicted quite well for the first 300 m downwind but then underpredicted the plume concentration by an order of magnitude at distances of 4 km downwind. The HOTMAC/RAPTAD model revealed a similar behavior. The inability of those two models to predict the trajectory of the plume and the observed limited vertical growth of the plume, in the downwind valley, are the likely causes of the underprediction. The RAMS model revealed very poor wind field and dispersion predictions based on the large grid spacing that was required (for this application) in order to make the computer run times manageable ... Smoke, Complex terrain, Dispersion modeling, Computer modeling, RA 3.

Government Reports Announcements & Index

Government Reports Announcements & Index PDF Author:
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 2022

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הזולה של דדי ואחרים

הזולה של דדי ואחרים PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Survey and Evaluation of Field Data Suitable for Smoke Hazard Model Evaluation

Survey and Evaluation of Field Data Suitable for Smoke Hazard Model Evaluation PDF Author: Anthony J. Policastro
Publisher:
ISBN:
Category :
Languages : en
Pages : 68

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Book Description
This report presents a summary and critical evaluation of the existing data on the dispersion of military smokes. Emphasis is placed on fog oil smokes in terms of the measurement of concentration, dosage, particle size distribution, and mass deposition rate. The suitability of the available data for evaluating atmospheric dispersion models for health and environmental impacts purposes is marginal. Several questions remain as to the adequacy of the sampling techniques used and the validity of some of the supporting meteorological data. The best of the existing dataw onf og oil smoke dispersion were acquired during the Smoke Week IIi and IV experiments. Keywords: Aerosol photometers; Plume models; Mathematical models. (author).

Government Reports Annual Index

Government Reports Annual Index PDF Author:
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1336

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Field Measurement and Model Evaluation Program for Assessment of the Environmental Effects of Military Smokes: Analysis Methods and Results of Hexachloroethane Smoke Dispersion Experiments Conducted as Part of Atterbury-87 Field Studies

Field Measurement and Model Evaluation Program for Assessment of the Environmental Effects of Military Smokes: Analysis Methods and Results of Hexachloroethane Smoke Dispersion Experiments Conducted as Part of Atterbury-87 Field Studies PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 89

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Book Description
The results of five dispersion experiments conducted using hexachloroethane (HC) smoke pots are described. The experiments included: (a) measurement of time-dependent release rate (4 trials) and exit temperature (1 trial), (b) measurement of meteorological variables using a 10-m instrument tower and a 2-m mast upwind of the smoke source, (c) sampling of the particulate phase at four heights on 46 sampling masts organized into four transects located between 60 and 500 m from the source, (d) twelve samples of the vapor phase which were chemically analyzed for four specific organic compounds and (e) determination of the particle size distribution at a single location using a quartz-crystal-microbalance cascade impactor. Chemical analysis methods for the particulate and vapor phases are described. All particulate samples were analyzed for zinc and aluminum; 10 of the most heavily exposed filters were analyzed for 45 elements using a combination of inductively coupled argon- plasma, atomic-emission spectroscopy (40 elements) and ion chromatography (5 elements). Twenty-two additional samples were analyzed for 11 elements. A gas chromatography method used to analyze the vapor samples is also described. The results of the study include: (a) information on the approximate composition of the HC smoke particulate and vapor phases, (b) determination of the HC smoke particle size distribution and (c) concentration data with accompanying meteorological and source information which are suitable for testing and improving atmospheric dispersion models. Keywords: Screening smoke; Obscuring smoke; Gas chromatography.

Atmospheric Dispersion Modelling

Atmospheric Dispersion Modelling PDF Author: Rod Barratt
Publisher: Routledge
ISBN: 1134194978
Category : Political Science
Languages : en
Pages : 265

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Book Description
To comply with legal and other standards, businesses and regulators are increasingly required to make decisions based on risk assessments of the potential effects of their activities on the environment. Atmospheric dispersion modelling is a cost-effective method, allowing various scenarios to be explored before expensive investment takes place. This guide offers advice on this environmental management tool. Unlike much of the previous literature, it doesn't focus excessively on the mathematical theory behind the modelling or on modelling for specific regulatory purposes. Instead, it offers an understanding of the background to the methodologies, providing exercises to develop the skills to carry these out and including examples of the use of commercially available models to enable the reader to assess the results of modelling for risk assessment.