Research And Application Of Engineering Calculation Method For Geothermal Wellbore Heat Loss

Geothermal energy is a new clean and efficient unconventional resource. Use of it is promising broadly because of abundant distribution. In tapping into geothermal energy, wellbore temperature field is an important data which provides a reference to optimization of drilling fluid, even lays the foundation for production and evaluation of heat reserve. It is crucial to reduce heat loss along shallow interval around non-net pay considering efficient use of geothermal energy. This paper presents a computing method to heat loss that is suitable for geothermal drilling through modeling of long cylindrical heat conduction based on heat transfer. It means using integration disperses each segment following heat conduction mechanism and wellbore segment. This gives total heat loss of one segment by addition of heat loss at each segment which is calculated with production of length and heat flow density from computation after dispersing each segment according to computing model.Geothermal temperature distribution along wellbore is simulated numerically by ANSYS software. As it shows, the temperature distribution varies with well depth at special moment. On the basis of modeling, a geothermal wellbore heat loss analysis software is programmed and applied in evaluating wellbore temperature in geothermal well of KENYA. It provides a theoretical reference to whether the insulation operation is performed or not at upper interval through simulating and computing heat loss at upper 1000 m non-net pay interval of geothermal well.