Evaluation of Thixotropic Models for Waxy Crude Oils Based on Shear Stress Decay at Constant Shear Rates

Applied Rheology

Teng Houxing¹  Guo Liping¹  Zhang Jinjun¹ 

[1] The MOE Key Laboratory of Petroleum Engineering/Beijing Key Laboratory of Urban Oil and Gas Distribution Technology, China University of Petroleum,Beijing102249, China;

关键词: waxy crude oil;    thixotropy;    shear stress decay;    model;    evaluation;   

DOI  :  10.3933/applrheol-20-53944

来源: DOAJ

【 摘 要 】

Thixotropy is an important rheological behavior of waxy crude oils. The objective of this paper is to demonstrate existing model’s abilities to describe shear stress decay behaviors of waxy crude oils at constant shear rates. Seven models specially developed for or currently used to waxy crude oils are reviewed as well as two viscoelasticthixotropic models for human blood. Stress decay behaviors were measured for four waxy crude oils and at various temperatures. Each of the models was used to fit the stress decay plots at a single shear rate, and at multiple shear rates, respectively. Globally, Zhao’s model, a complex viscoplatic model with two structure parameters and twelve physical & fitting parameters, matched the experimental plots better than other compared models. While the three models with viscoelastic backgrounds were not quite successful. For use of models, one may make choice by comprehensively considering a model’s complexity in mathematic form and abilities to describe the rheological behaviors.

【 授权许可】

Unknown