重力热管井筒伴热方式可行性分析

将重力热管的高效传热特性应用于井筒伴热过程，并与热流体循环伴热和电加热伴热两种传统方法进行对比，分析影响重力热管伴热效果的外部因素。结果表明，重力热管作为一种井筒伴热方式是可行的，空心抽油杆为工质提供工作环境。通过重力热管的热量存储和传导，将井筒下部流体多余热能通过自平衡过程传递给近井口管段内的流体，加热井筒上部温度较低的原油。与两种传统伴热方式相比，重力热管在无需补充能量的情况下，能起到均衡井筒温度场的作用，同时满足生产的要求。重力热管的伴热效果受到井底流体温度、下入深度、产量以及原油物性的影响：随着井底温度、下入深度、产量的增加，重力热管的伴热效果变好；原油物性直接决定重力热管能否在油井应用。图9参13

Feasibility of two-phase closed thermosyphon heating method

Two-Phase Closed Thermosyphon (TPCT) is used in the course of wellbore heating by utilizing its characteristic of efficient heat-transfer, and several external factors are analyzed by comparing with hot fluid circulation method and electric heating method. As a kind of wellbore heating method, TPCT is feasible in oilfields and hollow sucker rods can provide working environment for work fluid. Through heat stowing and heat conduction, TPCT can increase the temperature of the upper cryogenic fluid in wellbores by absorbing the surplus energy of the lower, high temperature fluid in the wellbores. Compared with the two conventional methods, the TPCT technology improves the temperature distribution along the wellbore without extra energy consumed and meets the demand of production at the same time. With the increase of downhole temperature, setting depth and yield, the effect of TPCT improves. Physical properties of oil determine directly whether TPCT is feasible or not in wells.