摘要
采用COMPASS(Condensed-Phase Optimized Molecular Potential for Atomistic Simulation Studies)力场,对β-HMX晶体的单轴压缩进行了分子动力学模拟,压缩方向分别垂直于β-HMX晶体的(100)、(010)和(001)晶面。模拟结果表明,垂直于不同晶面的单轴压缩得到的状态方程不同,显示出β-HMX晶体单轴压缩的各向异性。利用NpH系综对β-HMX晶体进行了绝热静水压缩模拟,得到的绝热静水压缩线处于等温静水压缩线的上方,与实验结果更加吻合。绝热压缩下,体系温度升高,各压力作用下体系温度的模拟结果与理论计算得到的冲击温度比较接近,说明COMPASS力场和NpH系综适用于模拟β-HMX晶体的绝热压缩。利用分子动力学方法模拟炸药的绝热压缩,可以预估炸药的冲击温度。
The uniaxial compression of β-HMX crystals in three orientations of（100）,（010） and（001） were calculated through molecular simulations using COMPASS（Condensed-Phase Optimized Molecular Potential for Atomistic Simulation Studies） force field.The isotherms of the three orientations are different,which indicates that the β-HMX has anisotropic compression property.The adiabatic hydrostatic compressions of β-HMX were also simulated in NpH ensemble.The adiabat is above the isotherms and in better agreement with the shock experiments.The temperatures of β-HMX were simulated by molecular dynamics and compared with the shock temperatures of β-HMX calculated with approximation theoretical method.Although there were some small deviations between the simulated and the calculated shock temperatures,the simulation of compression of β-HMX crystals in NpH ensemble is suitable for predicting the shock temperature of β-HMX explosive.COMPASS force field is applicable to describe the adiabatic compression of β-HMX.The simulation of adiabatic compression of explosive using molecular dynamics can predict the shock temperature of explosive.
出处
《高压物理学报》
EI
CAS
CSCD
北大核心
2010年第5期326-332,共7页
Chinese Journal of High Pressure Physics
基金
国家自然科学基金重点项目(10832003)
关键词
分子动力学
β-HMX晶体
压缩各向异性
绝热压缩
冲击温度
molecular dynamics
β-HMX crystal
anisotropic compression
adiabatic compression
shock temperature
