火烧油层注气井试井分析理论模型

为了监测火烧油层注气井的生产动态,提高火烧油层驱油技术实施的成功率,在火烧油层技术驱油机理的基础上提出了火烧油层复合油藏模式,建立并求解了火烧油层注气井试井解释模型。利用该模型可以对火烧油层注气井试井压降曲线进行解释,并求解流度比、扩散比以及各区的波及半径等参数。研究表明,火烧油层注气井试井典型曲线呈现3个“驼峰”和2个“驼谷”的特征,其中,无因次组合参数CDe^25主要影响典型曲线的早期特征;已燃区半径主要影响第1个“驼谷”的位置和第2个“驼峰”的持续时间,烧焦区半径主要影响第2个“驼峰”的峰值,热流体区半径主要影响第3个“驼峰”的位置;改变流度比主要影响各区过渡段的压力特征,各区流度比增大,在压力导数曲线上,其所对应的“驼谷”加深或“驼峰”的峰值增大,相比之下,改变扩散比对特征曲线的影响程度较小。

Theoretical model of well test analysis for gas injection wells of in - situ combustion

In order to monitor the production performance of gas injection wells of in - situ combustion,and to ensure the success rate of the in - situ combustion technology, the compound reservoir mode of in - situ combustion is proposed based on the mechanism of this technology. And then the well test interpretation model of gas injection wells of in - situ combustion is established and solved. With this model,the pressure drop curve of well testing is interpreted, and mobility ratio, diffusion ratio, sweep radius of each area and some other parameters are solved. The result shows that the typical curves of well test of the gas injection wells of in - situ combustion are characterized by three "humps" and two "valleys". The dimensionless combination parameter,CDe25,mainly affects the early stage of the typical curve,and the radius of the burned area mainly determines the position of the first "valley" and the duration of the second "humps". The radius of the coke - burning area mainly influences the peak value of the second " humps". The radius of the hot liquid areas mainly determine the position of the third "humps". Mobility ratio mainly affects the pressure performance of transition areas, in term of such laws that the corresponding "humps" or "valleys" on the pressure derivative curve will be more prominent with the increase of the mobility radio in each area. Comparatively,the dispersion radio have little influence on the typical curve of well tests.