复合油藏非自喷DST试井数学模型的建立及其解的特征

MATHEMATICAL MODEL FOR NON FLOWING DRILLSTEM TESTS (DST) IN COMPOSITE RESERVOIR

在低渗透油田的测试过程中，井筒中的流体常因流不出地表而在井筒中发生段塞式流动，使流动与恢复测试阶段的井筒压力均上升。针对这种流动特征，建立了描述复合油藏非自喷ＤＳＴ测试流动与恢复全历史的数学模型，并求得其拉氏空间解。由于考虑了流动期的流动特性，因此，该模型的解更能精确地反映地层特征。研究了拉氏反演后真实空间解的特性，给出了分析实测资料的具体方法。所得到的分析方法可用于分析钻井完井过程中的非自喷ＤＳＴ测试资料及所有低渗透油藏测试过程中的非自喷段塞流动试井资料。

During well testing in low permeability reservoir, the produced fluids could not flow out of the wellbore, and there occurred a slug flow at wellbore. The bottomhole pressure raised during production and shut in periods. A mathematical model for analyzing a completed pressure history of non flowing DST problem in combined field is proposed, and a Laplace solution for the model is presented. This model can describe flowing features during production and shut in periods. The properties of the solution in real space were studied. A method for analyzing testing record is given. The analysis method can be extended for the case of other slug flow well testing.