Plutonium explosive dispersal modeling using the MACCS2 computer code

Wang

Xiao

2012

AMR

The plutonium material in weapons grade nuclear device would be aerosolized and dispersed into the atmosphere if the device was involved in a high explosive detonation. It is significant to investigate the environmental and public hazard caused by the possible dispersion of plutonium. The original work is to determine the source terms of plutonium aerosol in certain nuclear accident scenario. In such scenario the inhalation of plutonium aerosols is the main human hazard source. Only the plutonium aerosols with aerodynamic diameter less than 10 μm are respirable and may ultimately lead to fatal human death. The field detonation test with plutonium by U.S. government is reviewed and the results indicate that for expected high explosive detonation scenario the plutonium source terms are 100 % aerosolization and 20 % respirable fraction. In order to find the aerosolized similarity of plutonium and several conventional metals, two detonation experiments in which the stannum foil and the vanadium powder are used as the replacement of plutonium respectively have been conducted by our group. After the detonation the metal aerosols are collected and analyzed. It has been found that the metallic powder is much easier to be aerosolized than the foil while the integrated aerosol source terms (respirable mass fractions) of stannum and vanadium are quite different with plutonium. Unlike the integrated aerosol data, the differential source terms (cumulative mass fractions via particle size) of the simulative samples are partially similar with plutonium.

Section: Plutonium Aerosol Source Term In He Detonationmentioning

confidence: 99%

Brief Analysis of the Simulative Plutonium Aerosol Source-Term in the Circumstance of High Explosive Detonation

Wang

Xiao

2012

AMR

“…Thus, ORC provides the most important explosive source term and dispersal distribution data of plutonium aerosols for future numerical simulation investigations (Dewar et al 1982;Boughton and DeLaurentis 1992;Homann and Wilson 1995;Steele et al 1998). Different numerical models such as DIFOUT (Luna and Church 1969), HOTSPOT (Homann and Wilson 1995), MACCS2 (Steele et al 1998), ERAD (Boughton and DeLaurentis 1992), etc., have been developed by Los Alamos National Laboratory (LANL), Lawrence Livermore National Laboratory (LLNL), and Sandia National Laboratory (SNL) for the simulation of plutonium aerosol dispersal. The former three models are based on the Gaussian plume model and the last one is a three-dimensional model calculated by Monte Carlo method.…”

Section: Introductionmentioning

confidence: 99%

Using silver as a surrogate for plutonium: An experimental study of the explosive silver aerosol source term

Aerosol Science and Technology

Hou

et al. 2016

An experimental method is developed for the purpose of simulating plutonium aerosol source terms with conventional metals in laboratory. In this method, metal samples are aerosolized by high explosive detonation in a containment vessel. Aerosols having aerodynamic diameter (AD) less than 10 mm are then collected by a cascade impactor and analyzed by atomic absorption spectroscopy. Two sets of experiments were conducted. In the first set, five candidate metal samples (Ag, W, Sn, Ce, and V) were tested. It is found that the cumulative mass distribution of silver under certain conditions was in good agreement with that of plutonium from the Operation Roller Coaster-Double Track experiment. Thus, silver is chosen as a surrogate to simulate the plutonium aerosol source term. In the second set, silver aerosol source term was studied in detail with different test configurations. The results demonstrate that the peak of the mass-size distribution of silver is in the AD range 1.1-3.3 mm. The amount and fraction of relatively small silver aerosols decrease significantly with time due to coagulation and deposition. Interestingly, the amount of silver in aerosols could be expressed as a quadratic function of the peak detonation pressure.

“…Because of the high activity, toxicity and long half life the plutonium aerosols resuspended in areas surrounding the source-terms have aroused great attention among the governments and public. In 1960s the research institutions of U.S. government invented several numerical models for hazard evaluation in the early stage of nuclear leak, such as HOTSPOT [1], DIFOUT [2], MACCS2 [3], ERAD [4] etc. However, during the long period after the releasing event, the deposited plutonium aerosols would release from the contaminated soil into the air due to the natural or artificial disturbances, which is named as the plutonium aerosol resuspension.…”

Section: Introductionmentioning

confidence: 99%

The Environmental Effect of Radioactive Particles in the Contaminated Sites with Resuspended Plutonium Aerosols

Wang

Xiao

2013

AMR

The plutonium material within the nuclear devices would be aerosolized and cause intense respirable hazards in the scenes of nuclear test and nuclear accident. The assessment of plutonium aerosol resuspension according to the typical radioactive contaminated sites would provide instructional data for the resuspended aerosol fluctuation study and edaphic cleanup, which can remedy the uselessness of aerosol diffusion model in the study of plutonium contaminated regions. The empirical model of plutonium aerosol resuspension is based on the aerophysics, the geognosy and the radiochemistry. This method was applied to analyze the representative plutonium contaminated regions. The results indicate that soil erosion is the intrinsic factor of resuspension process. The resuspended concentrations of plutonium aerosols in nuclear test sites are much less severe than those in the “non-nuclear” test sites (safety shots and simulated nuclear accident tests). Short-term, orders-of-magnitude fluctuations of the airborne concentrations are observed due to the natural and man-made disturbances. After systematic soil cleanup the resuspended plutonium aerosol concentration could fall down to the public allowable level.