液氦冲击压缩特性的理论计算

Theoretical Calculated Shock-Compression Properties for Liquid Helium

1.
Institute of High Temperature and High Pressure Physics, Sichuan University, Chengdu 610065, China;
2.
Laboratory for Shock Wave and Detonation Physics, Institute of Fluid Physics, CAEP, Mianyang 621900, China

摘要: 用量子力学修正的WCA液体变分微扰理论计算了液氦冲击压缩曲线，计算中体系分子间相互作用势选择EXP-6有效两体势模型，两体势参数通过对实验数据的拟和优选。计算结果在一次冲击压力范围内，冲击温度及压力与Nellis等人的实验数据符合很好，二次冲击数据与实验值稍有偏差，但也在其误差范围内，由于二次冲击只有一个实验点，因此实验数据不能提供更多的信息以供比较。计算结果表明与其他分子间相互作用势相比，选择值为12.7的EXP-6势更为准确地反映了液氦分子间的相互作用。
- 冲击压缩 /
- 液氦 /
- WCA状态方程 /
- 有效两体势
Abstract: For liquid helium, the modified WCA liquid perturbation theory was used to calculate Hugoniot curve using EXP-6 reference potential. The theory is generalized to include quantum effects by adding the first term of Wigner-Kirkwood expansion. The theoretical calculated pH and TH are in good agreement with experimental data up to 56 GPa where liquid helium is compressed to densities up to five times greater than the normal and heated to temperature up to 21 000 K. Parameters of EXP-6 potential are chosen as =12.7, r*=0.296 73 nm, /k=10.8 K respectively.
- shock compression /
- liquid helium /
- WCA equation of state /
- effective two-body potential

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