热力采油井现代试井分析方法研究

Study on Modern Well Test Analysis Methods for Thermal Recovery Wells

根据热采井油层的加热特点,建立了热采井双区试井数学模型,并求出了井底压力的解析解,分析了试井典型曲线的影响因素,结果表明,加热半径和流度比是影响典型曲线特征的主要因素,波及区越大,压力导数曲线上的第一平缓台阶越明显;流度比主要影响后期的压力时变特征,压力导数曲线的第二个“驼峰”峰值随流度比增加而增大。最后通过实例计算提出了热采井焖井试井解释方法。

A dimensionless mathematical model was developed based on the two regions composite formation characteristics after thermal fluid injection, and its analytical pressure solution has been found from Laplace transformation and Stenfest numerical inversion. Moreover, the factors on the typical curve of well tests are analyzed. It has been shown that heated radius and mobility ratio are the two major factors on wellbore pressure performance. The longer of first plat stage on pressure differential curve, the lager of area heated, and the bigger ' hump' on pressure, the mobility ratio of unheated and heated. Finally, the method of thermal recovery well testing interpretation is given to obtain some formation parameters for a field example.