Abstract: The fluid thermodynamic properties involving partial derivatives are related in some specific correlations with compressibility factor Z, derivative compressibility factors Zp and Zr and specific heat Cp. In order to recommend general formulas and tables for the calculation of ZP and ZT, two general analytical expressions of Zp(O)or(R) and ZT(O)or(R) based on Lee-Kesler equation are developed, and the tables of Zp(O),Zp(1), ZT(O), Zr(1) are provided, over the range Pr=0.1-10,Tr=0.3-4. Using the ZP(O)or(R),ZT(O)or(R) expressions or tables provided, the thermodynamic properties of non-polar or light polar fluids, such as the exponent of isentropic process, speed of sound, the difference or the ratio of specific heat Cp-Cv, Cp/Cv etc., can be calculated manually or with a computor. Some calculations of the thermodynamic properties indicated above for CO2, F-22, N2 show that the results are in good agreement with the data published. The error is allowable for engineering applications.

摘要： 本文用流体的压缩性系数Z、导数压缩性系数Z_P、Z_T及比热的特定关系式来表述常遇的含有热力偏导数的流体热力性质。为了推荐Z_P、Z_T的通用计算公式及图表,本文导出了Lee-Kesler方程导数压缩性系数Z_P~（（O）or（R））、Z_T（（O）or（R））的分析表达式。在P_r=0.1—10、T_r=0.3—4范围内,算得L-K方程Z_P（（O））、Z_P（（l））、Z_T（（O））、Z_T（（l））数值并列成表格。所提供的Z_P（（O）or（R））、Z_T（（O）or（R））表达式或表格,可用来机算或手算非极性和轻微极性流体的热力性质,诸如流体等熵指数、流体声速、等压及等容比热比、比热差等。 对CO_2、F-22、N_2进行了上述热力性质计算,所得结果和有关文献比较,误差在工程允许范围内。