裂隙岩体渗流-传热的时域半解析计算方法  

Temporal semi-analytical method for water flow and heat transfer in fractured rocks

作　　者：刘东东 项彦勇[1] LIU Dongdong;XIANG Yanyong(School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]北京交通大学土木建筑工程学院

出　　处：《中南大学学报（自然科学版）》2020年第2期523-531,共9页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51378055);中央高校基本科研业务费专项资金资助项目(2018YJS104)~~

摘　　要：针对饱和裂隙岩体渗流-传热问题,提出一种时域半解析计算方法。首先利用三维热传导方程的基本解建立岩石温度的时空域边界积分方程,通过对时间进行卷积积分将其简化为空间域的积分方程;应用有限单元法离散裂隙水的热对流方程,建立线性代数方程组,经过迭代计算直接得到裂隙水和岩石的温度。最后,通过1个核废处置库裂隙岩体渗流-传热算例,验证本文方法的有效性。研究结果表明:相比于拉氏变换半解析方法,本文方法具有计算过程更简单和计算结果更精确的特点,能用于分析稀疏裂隙系统中的水流-传热问题;裂隙水将核废物释放的热量传输至下游,有利于降低处置库温度。In view of the water flow and heat transfer in fractured-rock matrix,a temporal semi-analytical method was proposed.First,a boundary integral equation of rock temperature in spatial-temporal domain was established by using the fundamental solution of the three-dimensional heat conduction,and then the equation was simplified into a spatial domain equation by implementing convolution integral over time.Then,linear algebraic equations were formulated by combining the finite element equation of thermal convection in fracture water and previous boundary integral equation of rock temperature.Finally,the temperature of fracture water and rock matrix was solved by manipulating an iterative calculation.A numerical example of water flow and heat transfer in a nuclear waste repository was provided to verify the effectiveness of the proposed method.The results show that compared with the existing Laplace transformation semi-analytical method,the poroposed method in the paper is simpler and more accurate,and applicable to heat transfer problems of fractured-rock matrix with multiple parallel fractures distributed.The fracture water transfers the heat that is emitted from nuclear waste downstream,which contributes to the decline of repository temperature.

关 键 词：裂隙岩体 饱和渗流 三维传热 时域半解析方法 

分 类 号：P314[天文地球—固体地球物理学]