The fracture-hole description method of carbonate reservoir is different from that of conventional sandstone reservoir, the reservoir understanding, exploration and development are very difficult. This project abandons the traditional well testing interpretation, and intends to study a new set of theories and methods of well testing interpretation for fracture-hole reservoir. Starting from the three conservation laws satisfied by continuum mechanics (mass conservation, momentum conservation and energy conservation), fully considering the characteristics of bedrock, fracture and hole in formation, establishing the corresponding flow equation and finding the solution method of flow equation. The well testing analysis method of Ordovician fracture-hole reservoir in Tahe Oilfield is carried out, which provides a theoretical basis for well testing interpretation of fracture-hole reservoir.
The flow equations of wellbore, hole and formation are established by using three conservation laws, and the problem of well testing analysis of fracture reservoir that wellbore-hole connected is solved.
The theory pressure change in the hole is the coupling of flow and pressure fluctuation is presented for the first time, the equation of pressure satisfaction under the coupling of flow and pressure fluctuation is given, and the expression of pressure difference between hole and wellbore is obtained.
The hole in the formation is considered as the source sink term, and the strength of the source sink and the distance to the wellbore are explained by well testing analysis. The source and sink strength is transformed into the volume of the hole by reservoir engineering method.
The well testing interpretation method of fracture-hole reservoir is put forward. The well testing models of well-hole, well-hole-hole and well-hole-fracture-hole are established, and the well testing analysis char/method are obtained.
With the development and production of carbonate reservoirs, well testing analysis and productivity evaluation of fracture-hole reservoirs have attracted more and more attention, and related research papers have emerged. Although a large number of academic research has been carried out on well testing and productivity of carbonate reservoirs domestic and abroad, it can not solve the problem of carbonate pressure recovery well testing analysis in actual oil fields at present, and there is only a partially simplified triple medium model in commercial software.
In this project, the flow in the hole is regarded as the coupling of wave and flow; because the radius of the hole is much larger than the radius of the wellbore, the energy conservation is adopted when fluid flow from the hole to the wellbore; the hole in the formation is treated as the source and sink, so that the well testing problem of carbonate reservoir is simplified as "well-hole", "well-hole-hole" and "well-hole-fracture-hole".
The research results and technical policies are suitable for the well testing analysis of the whole carbonate fracture-hole reservoir, which has important guiding significance and high popularizing value for understanding the fracture-hole structure and distribution of carbonate fracture-hole reservoir, reasonable and effective productivity prediction, and reforming low (no) effective well.