基于广义Kelvin模型的非定常盐岩蠕变模型

来源期刊:中南大学学报(自然科学版)2020年第5期

论文作者:闫怡飞 韩伟民 闫相祯

文章页码:1337 - 1350

关键词:蠕变本构模型;非定常广义Kelvin模型;Heard稳态蠕变模型;二次开发;有限差分法

Key words:creep constitutive model; non-stationary generalized Kelvin model; Heard steady creep model; secondary development; finite difference method

摘    要:针对川东北油气田盐岩地层普遍出现的套损现象,对该地层段盐岩的蠕变特性进行研究。用非定常黏壶元件替换广义Kelvin模型中的线性黏壶元件,建立非定常广义Kelvin模型;将其与能够描述盐岩稳态蠕变特征的Heard模型进行串联,构建新的四元件NGKH盐岩非线性蠕变本构模型,可以描述盐岩的衰减蠕变阶段和稳态蠕变阶段特征。基于室内三轴蠕变试验结果,利用Levenberg-Marquardt算法对NGKH模型蠕变参数进行识别。基于FLAC3D的UDM接口程序,采用C++编程语言对其进行二次开发;并通过三轴蠕变试验的数值模拟对开发NGKH模型进行验证。研究结果表明:NGKH模型的拟合结果与室内试验结果吻合良好,该蠕变模型能够准确描述盐岩的非线性蠕变特性;通过黏弹性与非线性计算结果,验证了开发NGKH模型程序的正确性和合理性。

Abstract: The creep characteristics of salt rock were studied in northeastern Sichuan oil and gas field in view of the casing damage commonly occurring in salt rock formation. A non-stationary generalized Kelvin model was established by replacing the linear viscous component with a nonlinear viscous component. By connecting it with the Heard model, which could describe the steady creep stage of salt rock, a new non-linear four-element NGKH creep constitutive model for salt rock was constructed, which could describe the characteristics of decay creep stage and steady creep stage of salt rock. Based on the results of triaxial creep tests in laboratory, the creep parameters of NGKH model were identified by Levenberg-Marquardt algorithm. The NGKH model was redeveloped using UDM interface program of FLAC3D with C++ programming language, and verified by numerical simulation of triaxial compression tests. The results show that the fitting results of NGKH model are in good agreement with the laboratory test results, and the creep model can accurately describe the non-linear creep characteristics of salt rock. The correctness and rationality of developing NGKH model can be verified by the viscoelastic and non-linear calculation results.

有色金属在线官网  |   会议  |   在线投稿  |   购买纸书  |   科技图书馆

中南大学出版社 技术支持 版权声明   电话:0731-88830515 88830516   传真:0731-88710482   Email:administrator@cnnmol.com

互联网出版许可证:(署)网出证(京)字第342号   京ICP备17050991号-6      京公网安备11010802042557号