Abstract:In order to solve the pumpburning problem of screw pump wells, extend pump inspection cycle, and improve economic benefits, based on automobile sliding theory, heat generation rate model and unsteady temperature field model of rotor were established and solved with volumecontrol heat balance method. Pressurized heating up model was built according to the first law of thermodynamics. Stator temperature distribution in axial direction and fluid temperature distribution were determined through iterative calculation, and the distribution laws under different outlet pressure and production gas oil ratio were analyzed. The results show that because of interference fit and relative motion between stator and rotor, the rotor′s section temperature field is divided into high temperature zone and low temperature zone; an obvious spiral damage belt along axial direction has been found; the stator′s highest section temperature distributes in axial direction and internal fluid temperature distribution, dominated by inner pressure distribution, are divided into two stages and shift towards suction as the outlet pressure increases. The increase of production gas oil ratio weakens convective heat transfer between stator′s inwall and internal fluid, changes its physical property parameters, which accordingly causes the elevation of stator temperature and fluid temperature. Its effect on temperature field change is mainly on pump outlet.
[1]Woolsey K A. Improving progressing cavity pump performance through automation and surveillance[C]//Proceeding of Society of Petroleum EngineersProgressings Cavity Pumps Conference,2010:26-34.[2]Zhou Desheng, Yuan Hong. Design of progressive cavity pump wells[C]//Proceedings of Society of Petroleum EngineersProgressing Cavity Pumps Conference,2008:1-12.[3]Bratu C. Progressive cavity pump (PCP) behavior in multiphase conditions[C]//Proceedings of SPE Annual Technical Coference and Exhibition,2005.[4]Bratu C, Seience L. New progressing cavity pump (NPCP) for multiphase and viscious liquid production[C]//Proceedings of SPE/PS-CIM/CHOA International Thermal Operations and Heavy Oil Symposium,2005.[5]魏纪德, 郑学成, 岳莉,等. 采油螺杆泵定子温度场数值模拟分析[J]. 石油机械, 2006, 34(2): 11-14.Wei Jide, Zheng Xuecheng, Yue Li, et al. Numerical simulation on temperature field of progressing cavity pumps′ stator[J]. China Petroleum Machinery, 2006, 34(2): 11-14. (in Chinese)[6]杨秀萍,郭津津. 单螺杆泵定子橡胶温度场分析[J]. 润滑与密封, 2008, 33(7): 53-55.Yang Xiuping, Guo Jinjin. Study of temperature field for stator rubber of eccentric screw pump[J]. Lubrication Engineering, 2008, 33(7): 53-55. (in Chinese)[7]曹刚,刘合, 金红杰,等. 螺杆泵动力学热力耦合分析方法研究[J]. 计算力学学报, 2010, 27(5): 930-935.Cao Gang, Liu He, Jin Hongjie, et al. Thermalstructure coupling analysis of PCP dynamics[J]. Chinese Journal of Computational Mechanics, 2010, 27(5): 930-935. (in Chinese)[8]薛建泉,张国栋,吴慎渠,等.双热源作用下螺杆泵定子非稳态温度场数值模拟[J].中国石油大学学报:自然科学版,2012,36(3):130-134.Xue Jianquan,Zhang Guodong,Wu Shenqu,et al.Numerical simulation on unsteady temperature field of progressing cavity pumps′ stator with double heat source[J].Journal of China University of Petroleum: Edition of Natural Science,2012,36(3):130-134. (in Chinese)[9]苏亚欣.传热学[M]. 武汉: 华中科技大学出版社, 2009:78-87.[10]Noonan S G, Studer D, Skoczylas P, et al.A saskatchewan field trial to better understand downhole dynamics of PCP systems[C]//Proceedings of SPE Annual Technical Conference and Exhibition,2010:5734-5746.