新的气藏拟压力计算经验公式

A new empirical formula of pseudo pressure calculation for real gas

田津杰 李春兰 黄世军 李冬青 蒋银举

TIAN Jinjie LI Chunlan HUANG Shijun LI Dongqing JIANG Yinju

中国石油大学石油工程教育部重点实验室，北京　102249 华北油田公司第五采油厂，河北辛集　052360

Moe Key Laboratory of Petroleum engineering in China university of Petroleum Beij ing 102249 China no.5 oil Productionp lant Huabei oilf ield Comp any Xinj i 052360 China

对气体拟压力的计算，一般将气体拟压力简化为压力平方项，或直接应用数值积分方法进行计算，不能准确表征实际气藏的气体拟压力。为此，以某一实际气藏的气体组分为例，通过精确地计算黏度 和压缩因子 ，推导出这二者的乘积 随压力和温度变化的分段计算公式，得到了适用于不同温度和压力条件下干气气藏的真实气体拟压力计算的新经验公式。计 算结果表明，随着地层压力的增加， 逐渐增加；压力较低时， 随压力增大呈抛物线性增加，压力较高时， 随压力增大呈 线性增加；干气组分变化对拟压力的计算结果影响较小。新的经验公式计算结果与数值积分方法计算的拟压力结果相近。

Generally, pseudo pressure for real gas is calculated by simplifying pseudo pressure as pressure square or using numeri- cal integration directly, which can not exactly represent the pseudo pressure for real gas. With a gas composition of the gas ield as an example, the paper calculates viscosity μ and compressibility factor Z, and presents a new empirical formula of the product of μ and Z with pressurep and temperature t going on, and obtains pseudo pressure for different dry gas with deinite pressure and temperature. The results are received that Zμ increased with the respect to pressure, i.e. Zμ has a parabolic increase in an area of low pressure and a linear increase in an area of high pressure, and that gas composition has little effect on pseudo pressure calculation.