中高渗气藏压裂井产能预测及优化设计

Capacity prediction and optimization project on fractured well in medium-high permeability reservoir

目前,基于达西流动假设所进行的数值模拟对压裂气井生产动态的计算结果与实际相差较大.为此,在引入非达西因子的基础上,推导建立了压裂气井中气体在地层-裂缝中非达西渗流的数学模型,采用有限差分法求解了数学模型,模拟计算了不同裂缝参数和地层参数下的气井产量.计算表明,压裂气井中存在的非达西渗流对气井产量有显著影响;使用正交试验方法可快捷、准确地优选出最优的压裂方案.

Non-Darcy effect exists in the course of production in fractured gas well. Current calculated results from numerical simulation based Darcy flow condition have a big difference with real output. So introduced non-Darcy factor and built a mathematic model which described non-Darcy flow between formation and fracture in fractured gas well, then through finite difference method solved this mathematic model, and computed gas output in different fracture parameter and formation parameter. The result appears that non-Darcy flow in fractured well has an obvious effect on gas output. And it optimizes the fracturing project with cross experimental method which can help gas well project design.