The connected media of fault-karst reservoir are fractures

caves and pores

the decrease of pressure will lead to the decrease of permeability and conductivity

which will have an irreversible impact on oil well production. According to the stress-sensitive characteristics of fault-karst reservoir

72 groups of physical simulation experiments on conductivity are designed and carried out to analyze the stress-sensitive characteristics of different connected media and influencing factors. Based on the results of physical simulation experiment and the theory of porous flow

a numerical inversion model of flow in fractured solution reservoir is established

and the stress sensitivity effect caused by reservoir pressure drop on oil well production is studied. The results show that the pressure drop has great influence on the conductivity

productivity and recovery ability of different connected media. The pressure inflection points of fracture type

karst cave type and pore type are 5.3 %

20.4 % and 35.1 %

respectively

and the conductivity loss of the first two are 99.7 % and 45.0 %. The conductivity loss of pore type decreases linearly in the test range. The research on the characteristics of pressure drop inflection point provides the basis for reasonable production control and the determination of energy replenishment time

and has important guiding significance for stable production of oil wells.