In this paper, a new prediction equation for compressed liquid isochoric heat capacity (c_v) was developed based on the corresponding states principle (CSP). By knowing acentric factor (ω), critical parameters (T_c, p_c and v_c) and ideal gas isochoric heat capacity (c_v,0), the new equation could predict c_v for pure fluids and mixtures (including polar and nonpolar fluids) at 0.25 < T_r < 1 and 0.5 < p_r < 10. The overall average absolute relative deviation (AARD) of the new equation for 25 pure fluids and 10 mixtures are 2.21% and 1.62%, respectively. A comparison was conducted between the new equation and other models (PR EoS, Helmholtz energy EoSs, generalized equation (GE) of Zhong et al. [1] and corresponding states equation (CSE) of Sheng et al. [2]). The new equation significantly improves the prediction performance for the heat capacity of important fluids, such as halogenated hydrocarbons, carbon dioxide, water and so on, compared with the existing models. Although the prediction performance of the new equation is slightly worse than that of the Helmholtz energy EoS, the new equation has a simpler form and more powerful prediction performance than the Helmholtz energy EoS for mixtures.

在本文中，对于压缩的液体等容热容量的新的预测方程（Ç _v）基于对应的状态原理（CSP）的开发。通过知道偏心因子（ω），临界参数（Ť _Ç，p _Ç和v _{C ^}）和理想气体等容热容量（ç _v，0），则新的方程可以预测Ç _v为纯流体和混合物（包括极性和非极性流体）在 0.25 <  T _r  < 1 和 0.5 <  p _r < 10. 新方程对 25 种纯流体和 10 种混合物的总体平均绝对相对偏差 (AARD) 分别为 2.21% 和 1.62%。将新方程与其他模型（PR EoS、亥姆霍兹能量EoS、Zhong等人[1]的广义方程（GE）和盛等人[2]的相应状态方程（CSE））进行了比较。与现有模型相比，新方程显着提高了对卤代烃、二氧化碳、水等重要流体热容量的预测性能。虽然新方程的预测性能比亥姆霍兹能量EoS略差，但新方程比亥姆霍兹能量EoS对混合物的形式更简单，预测性能更强大。