Research On Interpretation Method Of Water Injection Profile Based On Distributed Optical Fiber Temperature Sensor

Water injection development is an efficient means of enhancing oil recovery.How to monitor and evaluate the effects of water injection is a crucial concern.Monitoring production well performance,evaluating water injection,and diagnosing the success of fracturing operations can be accomplished with temperature logging systems.Typical temperature logging methods are unable to monitor the temperature field in a high temperature and pressure environment for an extended period of time.Temperature distribution is affected by the movement of sensors and equipment;therefore,temperature logging is not always the ideal method for understanding temperatures.The expansion of optical fiber technology in recent years has revived the interest of specialists in temperature logging systems.The distributed optical fiber temperature sensor is a new type of sensor that can get high-resolution temperature data from boreholes all the time.It has the benefits of being sensitive,accurate,quick to respond,and able to track the temperature of more than one target point at the same time.It can monitor and evaluate the effect of underground water injection in real-time.The optical fiber material’s anti-interference and anti-corrosion properties make it suited for the complicated environment in the well,and its ability to be permanently fixed in the wellbore contributes to the quantitative interpretation of the downhole water injection profile.First,this paper talks about what oil field water injection development is and why it’s important.Then,the distributed optical fiber temperature sensor technology is explained in detail from the points of view of its principle,how it is installed,its benefits,and where it can be used.Finally,the theory of the mathematical model of fluid movement is introduced,and the process of establishing the temperature field in the mine is described in detail,based on the established mathematical model.Then,the component of the temperature inversion model of the water injection well is introduced,the temperature inversion model based on the enhanced whale algorithm optimized BP neural network is established,the distribution of oil and water after water injection is deduced to evaluate the effect of water injection,and a complete forward and inverse model of the temperature profile of water injection is built.Two approaches to the quantitative calculation of the water injection profile are utilized to lessen the workload of the forward modeling process when dealing with actual means of production.Lastly,the software implementation for quantitative water injection profile calculation is presented.The final software tool is capable of loading dispersed optical fiber temperature data,preprocessing the temperature data,quantitatively calculating the water injection profile,and visualizing the results.The research findings indicate that the distributed optical fiber temperature sensor technology can be used to monitor the water injection effect in real time,and the water injection profile can be interpreted by establishing the forward and backward temperature models.This method has the advantages of high precision and good real-time performance and can effectively enhance the efficiency and precision of water injection development.