炸药化学爆炸条件下模拟钚气溶胶扩散研究

The safety study of weapons-grade plutonium is of fundamental importance in the development and stockpiles of nuclear warhead and of great concern by the nuclear powers. The plutonium in a warhead could be aerosolized and released into the environment if involved in a explosive detonation or deflagration. It is essential to obtain the source term (the total dispersed mass and the size distribution) and the dispersal data of plutonium aerosol for risk assessment and emergency response in such accidents. Considering the high risk of plutonium aerosol experiments, we plan to use silver as a surrogate for plutonium to study the aerosol source term and dispersal characteristics in this project. The physical work capacity of explosive detonation and deflagration will be quantitatively calculated by coupling fluid-structure simulation. Then the source term and dispersal tests of silver aerosol in certain accidental scenarios will be conducted in the 40-kg Contained Firing Facility and in outfield, respectively. The relationship mapping the source term of silver aerosol to that of plutonium aerosol will be used to estimate the source term and dispersal data of plutonium and to improve the aerosol dispersal model. The ultimate aim is to establish the capability to estimate the plutonium aerosol diffusion in explosive detonation and deflagration accidents, providing necessary data for the environmental risk assessment.

钚材料的安全性研究是核战斗部研制和库存阶段重要的基础工程研究课题，业已受到各核大国的极大关注。当炸药发生化学爆炸事故（爆轰和爆燃）时核战斗部的钚材料组件存在气溶胶化并泄露至周边环境的风险。获得泄露钚气溶胶的源项参数和扩散分布是开展事故应急处置和危害评估的前提。鉴于直接开展钚气溶胶实验的高风险性，本申请项目提出利用金属银进行炸药化爆条件下气溶胶源项和扩散实验、结合不同反应烈度的炸药做功及气溶胶扩散数值模拟开展炸药化爆条件下模拟钚气溶胶源项和扩散研究的思路，开展不同反应烈度的炸药做功能力标定及化爆装置设计，进而以此为输入分别于40 kg TNT当量爆炸塔和外场开展银气溶胶源项、扩散实验，利用“银-钚”源项映射关系推算钚气溶胶源项参数和扩散分布，校验和修正气溶胶扩散数值模型，最终建立炸药化爆事故条件下钚气溶胶扩散分布的预测能力，研究成果将为核事故后的钚气溶胶安全性评估提供必要的基础参考数据。