Modeling the viscoelasto-plastic behavior of waxy crude

作     者：Teng Houxing Zhang Jinjun 

作者机构：National Engineering Laboratory for Pipeline Safety/Beijing Key Laboratory of Oil and Gas Distribution Technology China University of Petroleum 

出 版 物：《Petroleum Science》 (石油科学（英文版）)

年 卷 期：2013年第10卷第3期

页      面：395-401页

核心收录：

学科分类：081702[工学-化学工艺] 0709[理学-地质学] 0819[工学-矿业工程] 0808[工学-电气工程] 08[工学] 0820[工学-石油与天然气工程] 0817[工学-化学工程与技术] 0707[理学-海洋科学] 0818[工学-地质资源与地质工程] 0708[理学-地球物理学] 0807[工学-动力工程及工程热物理] 0815[工学-水利工程] 0816[工学-测绘科学与技术] 0827[工学-核科学与技术] 0813[工学-建筑学] 0703[理学-化学] 0814[工学-土木工程] 0825[工学-航空宇航科学与技术] 0704[理学-天文学] 

基　　金：the financial support from the National Natural Science Foundation of China (Grant No.51134006) Science Foundation of China University of Petroleum (Beijing) (Grant No.LLYJ-2011-55) 

主　　题：Thixotropy viscoelasticity viscoelasto-plastic model thixotropic model waxy crude 

摘      要：Waxy crude oil exhibits complex rheological behavior below the pour point temperature, such as viscoelasticity, yield stress, and thixotropy, owing to the formation of a three-dimensional spongelike interlock network structure. This viscoelasto-thixotropic behavior is an important rheologieal behavior of waxy crude oils, determining the flow recovery and safe restart of crude oil pipelines. Up to now, the thixotropic models for waxy crude have been all viscoplastic models, without considering the viscoelastic part before the yield point. In this work, based on analyzing the variation of the elastic stress and viscous stress in the Mujumbar model, a new viscoelasto-plastic model is proposed, whose shear stress is separated into an elastic component and a viscous component. The elastic stress is the product of the shear modulus and elastic strain; the shear modulus is proportional to the structural parameter. For the elastic strain, we followed the line of Zhu and his coauthors and assumed that it may be expressed by an algebraic equation. The model is validated by stepwise shear rate tests and hysteresis loop tests on Daqing and Zhongyuan waxy crude. The results show that the model＇s fitting and predictive capability is satisfactory.