It is difficult to accurately predict gas well deliverability of Sulige Gasfield because of its complex sand body shape,low controlled reserve of a single well and rapid decline of formation pressure. Based on the study of characteristics of sand bodies of Sulige Gasfield,four superimposed sand models and a two - region permeable flow model are put forward. Dynamic gas reserve and cumulative gas reserve of near Well I Region and far Well II Region are calculated respectively by using material balance method of natural water drive and cumulative production,and therefore boundary formation pressure at different production time can be obtained by iteration. Further more,gas deliverability equation fit for complex shape sand bodies with small reserve of Sulige Gasfield is established with the combination of gas deliverability equation under pseudo steady state flow. The distribution characteristics of reservoir pressure complex shape sand bodies under different permeable flow modes and the rapid drop of formation pressure of gas wells in small reserve reservoirs are considered in the model. The practical application shows that the deliverability calculated with the model is accurate and satisfactory and the error is within 10% .%苏里格气田砂体形状复杂,单井控制储量低,地层压力下降快,准确预测气井产能极其困难.基于苏里格气田砂体形态特征研究,总结出4种砂体叠置模式和两区渗流模式.借鉴天然水驱气藏物质平衡法,结合累计产量法,分别计算近井Ⅰ区和远井Ⅱ区动态储量及累计供气量,进而通过迭代求取不同生产时间的边界地层压力,然后联立拟稳定状态流动的气井产能方程,建立了适合苏里格气田复杂形状砂体小储量的产能计算模型模型既考虑了复杂形状砂体不同渗流模式下的储层压力分布特征,又考虑了小储量气井地层压力下降快的特点.实例应用表明:计算的产能准确,误差在10％之内,满足工程需要.
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