Study On Fractured Horizontal Well Production Profile Interpretation Based On Distributed Temperature Sensing

The combination of horizontal well drilling technology and hydraulic fracturing technology has always been the main driving force for the successful development of unconventional oil and gas resources.After the implementation of fracturing measures in oil and gas wells,it is necessary to evaluate the fracturing effect and obtain fluid production profile distribution,bottom hole flow conditions,etc.,which can be used to control and optimize the production of fractured horizontal wells and guide the subsequent fracturing design.Therefore,the monitoring and interpretation of fluid production profile of fractured horizontal wells is of great significance to the exploration and development of unconventional reservoirs.Based on conservation of mass,conservation of momentum and conservation of energy,considering various micro thermal effects such as heat conduction,heat convection,viscous dissipation and the Joule Thomson effect,this paper establishes a model of wellbore temperature profile for fractured horizontal wells.And the Markov chain-Monte Carlo inversion algorithm is used to establish the fractured horizontal well production profile interpretation model.Taking a fractured horizontal well as an example to analyze the fluid production profile,the research results show that the temperature change of the wellbore fluid of a fractured horizontal well is affected by many factors,including the wellbore fluid and the inflow fluid of the reservoir,the absorption of heat from the formation around the wellbore,the friction with the tube wall during the flow process,and the Joule Thomson effect of the inflowing fluid and some other thermal factors.Under the parameters studied in this paper,the temperature of the formation fluid increases rapidly in the radial inflow zone,while the temperature of the wellbore fluid increases slowly in the non-fractured zone.With the increase of the half-length of the fracture,the radial flow into the fracture area increases,and the temperature change in the fracture area becomes more obvious.With the increase of fracture conductivity and fracture height,the heat generated by friction of formation fluid decreases,and the temperature change of fracture area decreases.The closer to the toe of the wellbore where the flow of the oil and water change,the more the fluid temperature in the wellbore will be affected by the formation inflow fluid,and the more obvious the fluid temperature changes in the fracture area will be.In the example well,the error between the flow inversion value and the theoretical value is less than 15%.This method can be used to interpret the production profile of the fractured horizontal well,and also provides a certain basis for evaluating the fracturing effect.