Study On The Visco-elastoplastic Destruction Of Gelled Crude Oil

This research was based on the Sudan GNPOC and Nanyang crude oil. Based on crystallization kinetics, relative crystallinity was defined by storage modulus is analyzed the characteristic of crystallization during the cooling process and constant temperature process. The precipitation of wax crystals in various stages was observed by digital microscopic imaging system and parameters of wax crystals were statistic analyzed comprehensively in the whole process of the microscopic experiment. This article established the relationship between energy storage modulus and waxy area & the number of particles. Meanwhile, this article analyzed the rule and mechanism of storage modulus changing with micro-parameter. This article studied the rule of gelled crude oil energy storage modulus changing with temperature, frequency and amplitude under large amplitude oscillatory shear. Based on multiple linear regression method, this article built an equation between storage modulus and waxy area,number of particles, waxy volume fraction, box dimension. A storage modulus calculation model was got.The relationship between microscopic parameters and macroscopic rheological parameters was established. Through the micro-parameter change regulating during constant temperature process, this paper found that high cooling rate by varying the crystallization process improves the oil rheological properties Based on crystallization kinetics,this paper explained the mechanism that the structure recovery rate increases with pre-shearing rate during constant temperature process An empirical formula which can describe the rule of gelled crude oil energy storage modulus changing with under large amplitude oscillatory shear was proposed. This empirical formula has high fitting precision and its parameters have clear physical meaning.Based on Kachanov damage theory, the damage variable was introduced and coupled with Hooke’s mode to build an elastic damage body. This paper replaced the Hooke’s model in Burgers model which can describe the gelled crude oil transient creep process and steady state creep process with the elastic damage body and then build the visco-elastoplastic damage model. This paper analyzed the creep rule of gelled crude oil under different temperature, cooling amplitude and pre-shearing. The sticky visco-elastoplastic damage model in this article is nonlinear and has high fitting precision and its parameters have clear physical meaning. A storage modulus...