高温高密度氩物态方程研究

用Exp-6有效两体势模型和液体变分微扰理论计算了液Ar冲击压缩曲线,在35 GPa以下的压力范围内计算的冲击压缩曲线与Thiel 及Nellis等人的实验数据进行了比较.液体分子间Exp-6有效两体势参数根据实验数据计算优选出最佳值,计算结果表明得到的优选参数较为准确地描述了液Ar分子间相互作用.由理论结合实验数据可以认为液氩体系在冲击压力36 GPa以下无相变现象.对较高冲击压力下理论计算的冲击曲线和实验结果之间的偏差作了分析,结合不透明度实验的结果,得到当压力超过35 GPa,温度在12 000 K

Study for equation of state of dense argon

The variational fluid perturbation theory is used to calculate the Hugoniot curve of liquid Ar using the Exp-6 reference potential. Parameters of Exp-6 potential are determined from the X-ray diffraction experiment. The theoretical calculated P and T are good in agreement with those of experimental data up to 35 GPa.At higher pressure and temperatures, the theoretical calculated P and T are higher than experimental data. According to the result of opacity experiments, we think that at higher pressure and temperature, by absorbing some of shock energy, the excited electrons act as thermal sinks, keeping the temperature down and lowering the pressure.