中文摘要：

本文利用统计热力学中的BH微扰理论建立数学模型，推算了Ar超临界区域比定容热容，与文献值比较平均偏差为9．54％。引入了修正函数，重新对比热容公式进行推导，再次对Ar超临界区域部分比定容热容进行计算，计算平均偏差0．39％。对CO、CO2、CH4等其余11种简单气体的超临界比定容热容进行计算，平均偏差在1％左右。最后给出了计算中各物质势能参数值。

英文摘要：

The model to calculate the volumetric heat capacity of supercritical fluid was derived using BH perturbation theory in statistical mechanics. The heat capacities of Argon were calculated using the model. Compared the with reference values, and the the total average absolute deviation of heat capacity for Argon was 9.54 %. The heat capacities of Argon, CO, CO2, CH4 and other fluids were also calculated after a modification function was employed to modify the model. The total average absolute deviation was about 1%. The potential energy parameters of the fluids were also acquired for further research of thermodynamic properties.