气藏气体体积系数计算公式的修正

Modification of Calculation Formula for Gas Reservoir Volume Factor

介绍了石油工程中气藏气体体积系数的计算公式,分析了计算公式的不足,提出了计算公式的修正方法。采用石油工程中常用的PREOS和Gopal(1977)法计算偏差系数,利用修正的计算公式对10个甲烷摩尔分数为50.56%～97.75%的气藏气体体积系数进行了计算并与实验值比较,其平均相对误差分别为1.325%和3.173%;而石油工程中现有的计算公式对这10个相同气藏气体体积系数计算的平均相对误差分别为1.867%和3.701%。结果表明,修正的计算公式提高了计算精度。

The calculation formula for gas reservoir volume factor in petroleum engineering is introduced. The shortage of calculation formula is analyzed. A modified method is proposed for the calculation formula for gas reservoir. The deviation factor is calculated by PR EOS and Gopal （1977） methods widely used in the petroleum engineering. The gas reservoir volume factor calculation is performed for ten gas reservoir fluids with methane content ranging from 50.56 to 97.75 percent and compared with experimental data. The relative errors average 1.325% and 3.173%, respectively, with the modified calculation formula, compared with the average relative errors of 1.867% and 3.701% with available calculation formula. The results show that the modified calculation formula can improve the prediction accuracy for the gas reservoir volume factor.