Influence Factors Of Horizontal Well Perforation Hydraulic Fracturing Based On Hydraulic-Thermal-Mechanics Coupling Model

Deep geothermal power generation technology has become one of the research hotspots under the background of "dual carbon".The deep geothermal energy is mainly stored in the hot dry rocks(HDR)reservoir.However,due to the tight rock mass,the geothermal reservoir does not have the exploitation conditions,the geothermal reservoir needs to be reformed by hydraulic fracturing technology.Fixed surface perforation is one of the most commonly used techniques in hydraulic fracturing.However,the existing hydraulic fracturing theory is mostly based on the practical experience of oil and gas stimulation,and its conclusions can not adapt to the engineering practice of HDR.To cope with the above problems,this paper conducts a study on the influence of injection parameters on fracturing results in fixed surface perforation fracturing and the optimization of injection parameters.This paper established a fixed surface perforating fracturing model of HDR horizontal well,and compared the fracturing results with different perforating parameters.The paper shows that the perforation spacing is the main factor affecting the effect of fixed surface perforation fracturing.The larger the perforation spacing is,the stronger the independence of perforation is,and the larger the damage volume of rock is.However,the micro-fractures around the pores are not easily guided by other perforations,which is not conducive to the formation of complex fracture networks.The influence of perforation parameters on the perforation distance determines the influence of perforation parameters on fracturing.In this paper,the sensitivity of hydraulic fracturing results to perforation parameters and their interaction in different fracturing time is analyzed by orthogonal test.It is found that the sensitivity and influence significance of the perforation depth are far superior to other parameters.Adjusting the perforation density is a way to improve the fracturing efficiency by exchanging "quantity" for "time".The perforation Angle is one of the decisive factors affecting the perforation spacing,and a reasonable perforation Angle is conducive to the formation of complex fracture structure.The interaction between perforation size and perforation parameters has little effect on fracturing.This paper is of great significance to the application of fixed surface perforation technology in HDR development.At the same time,reasonable suggestions are put forward for optimizing perforating parameters,which is helpful to obtain complex fracture structure and improve thermal mining efficiency.