Experimental study on physical simulation of seepage mechanism in multilayer gas reservoirs

In order to clarify the production characteristics and seepage mechanism of Shenmu gas field during multi-layer combined production, a physical simulation experiment with fixed nozzle opening for double-layer combined production was designed and made by combining different cores in parallel to study the effects of reservoir physical properties, reserves, working system, etc. on the seepage characteristics of double-layer combined production of gas reservoirs. The experimental research shows that when the production system changes, there is a phenomenon of back irrigation; In multi-layer combined production, the flow of each layer is mainly affected by permeability in the early and middle stages of production, while the flow of each layer in the late stage of production is jointly affected by permeability and reserves; Low production allocation in strongly heterogeneous reservoirs is conducive to enhancing oil recovery, while high production allocation in homogeneous reservoirs is conducive to enhancing oil recovery.