G函数压降分析方法优化及应用

Pressure Drop Analysis Methods for Small-scale Fracturing

基于体积平衡原理,通过G函数压降分析的方法,建立了小型压裂压降曲线分析模型,并通过实例计算分析进行曲线拟合的对比性分析,在此基础上优化了G函数压降分析方法。研究结果表明:关井后dp/dG在0~3000间大幅波动,在关井后期dp/dG显示为水平特征,Gdp/dG显示为直线特征,G值分布在0~0.83之间。此时显示压裂液滤失与压力无关,得到拟合压力为9.25 MPa,验证了优化后的G函数压降分析方法具有更强的实用性,可应用于裂缝性储层。

Small-scale fracturing pressure drop curve analysis model was established by G function of pressure drop analysis method based on the volume balance principle to create. We compared the curve fitting method and improved G function drop analysis method through the instance of the computational analysis. The result shows that the value of dp/dG waved in 0~3 000 after shut-in, curve dp/dG shows level and Gdp/dG shows line feature later while G is 0~0.83. Now the fluid loss is pressure-independent and fitting pressure is 9.25 MPa. It proved that improved G function drop analysis method has wider applicability, including fractured reservoirs.