炸药爆轰产物Jones-Wilkins-Lee状态方程不确定参数

Jones-Wilkins-Lee (JWL)状态方程是一种不显含化学反应、由实验方法确定参数的半经验状态方程, 能比较精确地描述爆轰产物的膨胀驱动做功过程. 在JWL状态方程中有多个未知(不确定)参数需要确定. 传统的确定JWL状态方程参数的方法是“调参数”, 人为因素影响较大, 无法给出参数的不确定性信息. 本文利用贝叶斯分析方法研究了炸药的不确定参数, 该方法能够基于以往的认识、实验和模拟数据标定(calibration)不确定参数. 在本文结果中, 不确定参数的后验分布均值与文献结果相符合, 基于参数标定结果的数值模拟90%置信区间完全包含实验数据. 数值标定结果说明贝叶斯参数标定适用于确定样品炸药的JWL状态方程参数. 特别是, 在本文JWL状态方程参数标定过程中极大地减少了人为因素的影响.

Uncertain parameters of Jones-Wilkin-Lee equation of state for detonation products of explosive

Equation of state of detonation products possesses various types of mathematical expressions which describe the relation between pressure and volume. Jones-Wilkin-Lee (JWL) equation of state is a widely used equation of state of detonation products because of its simplicity in hydrodynamic calculations. The JWL equation of state may accurately describe the process of expansion drive of detonation products. The JWL equation of state contains parameters, and describe the relation among the volume, energy and pressure of detonation products. These parameters may be determined by detonation experimental data and numerical method. Traditional numerical method is adjusting parameters based on experimental data and numerical experience. Obviously, artificial ingredient may affect the calibrating result in traditional method. This paper uses the Bayesian method to determine the unknown (uncertain) parameter of JWL equation of state for detonation products. The method can calibrate the uncertain parameters based on the known parameter information, the experimental and simulating data. The results of the paper are consistent with those in the reference papers. By theoretical analysis the calibration result accords with the physical signification of the parameters of JWL equation of state. The epistemic uncertainty is slightly reduced. The calibration result collects all the parameter information in the prior parameter information, experimental data and numerical results. The experimental data are totally included in a 90% confidence interval of simulation. The numerical result shows that this method can be used to study the uncertain parameter of JWL equation of state for some sample explosives. Especially, the method reduces the artificial ingredient in the parameter calibration.