摘要
The riserless mud recovery(RMR)system abandons the riser used in conventional offshore drilling,and the drill string above the seabed is directly exposed to seawater,resulting in convective heat transfer from the drilling fluid in the drill string to seawater.Therefore,the wellbore temperature distribution in the RMR system is quite different from the conventional offshore drilling.In this paper,based on the heat transfer characteristics of the RMR system,a mathematical model of the thermal field of the RMR system is established.The data used in this paper come from a vertical well in the South China Sea.Computational Fluid Dynamics(CFD)software is used to simulate the temperature distribution in drill string at different seawater depths and different formation depths in this paper,and the simulation results are compared with the calculation results of the mathematical model,so as to verify the feasibility of the mathematical model established in this paper.Combined with the calculation results of the mathematical model,this paper also explores the effect of different discharge capacity and different injection temperature of drilling fluid on the wellbore temperature change.
基金
The financial support from the Natural Science Foundation of China(NSFC)(No.51274168)
the National Key R&D Program of China(No.2018YFC0310202)is gratefully acknowledged。
