流动物质平衡法广泛应用于压力测试和油藏物性缺乏的致密气藏动态储量的评价,但其忽略了天然气黏度和压缩系数的乘积随压力的变化,存在较大的误差.针对此问题,提出修正的流动物质平衡法,考虑了压力对天然气黏度和压缩系数的影响,并推导出修正的流动物质平衡方程.鄂尔多斯盆地致密气藏应用实践表明:流动物质平衡法计算结果偏小,气藏的生产压差越大,误差越大,最高可达22.76%;修正的流动物质平衡法计算的单井动态储量准确性高,误差小于6%,具有较好的实用性.该研究对于气藏合理开发方案的制订和经济高效的开发有重要的指导意义.%The flowing material balance is widely used in evaluating the dynamic reserve of tight gas reservoir in case of lacking pressure test and reservoir properties.However,the variation of product between natural gas viscosity and compressibility with pressure is neglected,which will result in a relatively large prediction error. A modified flowing material balance method is proposed to improve this problem. The effects of pressure on natural gas viscosity and compressibility are taken into consideration to deduce a modified flowing material balance equation.Field appli-cation in the tight gas reservoir of Ordos Basin indicates that the flowing material balance will underestimate its dy-namic reserve and the error with a maximum of 22.76% increases with the increase of producing drop. The single-well dynamic reserve can be more accurately calculated by this new modified flowing material balance equation. The corresponding error is less than 6%,which shows a prospective practicability. This research could provide signifi-cant guidance for gas reservoir development program design and economical-efficient development.
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