Numerical simulation of wellbore temperature during high-pressure deep well kills

According to the characteristics of normal circulation and reverse circulation kills, considering the axial heat transfer, radial heat transfer, convection heat transfer and friction acting heat and the like, a two dimensional transient forecasting model of wellbore temperature field of circulation kill process was established. The prediction model has been solved by finite difference method. Wellbore temperature of normal circulation and reverse circulation kill were numerical simulated for a high- pressure deep well, the results show that wellhead drainages temperature in normal circulation killing is higher than that in the reverse circulation killing, and the bottomhole temperature first decreased quickly and then gradually reached stable during the killing time, finally, bottom temperature in normal circulation killing is higher than that in the reverse circulation kill. The effects of discharge capacity, well depth, inlet temperature and tubing size on the wellbore temperature field were analyzed. The analysis shows that: the influence degree in descending order of the four factors is well depth, discharge capacity, tubing size and inlet temperature, which provides theoretical references for wellbore temperature control in field operation.