影响防砂气井产能的因素分析

Factors of Effecting the Productivity of Gravel Packed Gas Well

研究了出砂后砾石充填防砂气井的流动模式 ,认为气体从供给边缘到井筒的流动是由流动规律不同的 4部分组成 ;在考虑紊流对流动阻力影响的基础上 ,研究了各部分流动阻力的计算方法 ,从而建立了防砂气井产能预测模型 ;通过计算分析了影响气井产能的主要因素。研究表明 :①防砂气井的压降主要发生在射孔孔眼内及其附近地层 ;②射孔孔眼内填满地层砂比填满砾石时的流动阻力大的多 ,因此 ,将每个孔眼填满砾石是提高防砂气井产能及防砂有效期的根本保证 ;③井筒内按单向流、径向流及发散流计算流动阻力时 ,三者有较大差别。因此 。

The flow mode of gravel pack of gas well was studied by this dissertation. The flow from supply edge to well bore can be divided into four parts. The method to calculate the pressure drop of different parts was developed which consider the turbulent effect of gas flowing in that parts. The main factors that effect the productivity of gas well have been analyzed by calculation.The results show that: the pressure drop of sand control gas well mostly takes place in perforation pore and its around; the pressure drop in perforation is much bigger when it filled by formation sand than by gravel, so that, perforation filled by gravel is important to ensure high productivity and long effective time of sand control gas well; the pressure drop in gravel packed well bore is different when calculated by linear flow, radial flow and divergent flow. Therefore, the choice of flow model in well bore will effect the productivity of gravel packed well.