考虑流体相变效应的粗糙裂隙非线性渗流换热机理  

Investigating nonlinear flow and heat transfer in rough fractured rock by considering fluid phase transition

作　　者：刘先珊[1,2,3] 罗晓雷 白冰 魏宁[4] 刘少炜[5] 张普纲 李满 潘玉华 LIU Xianshan;LUO Xiaolei;BAI Bing;WEI Ning;LIU Shaowei;ZHANG Pugang;LI Man;PAN Yuhua(School of Civil Engineering,Chongqing University,Chongqing 400045,China;Key Laboratory of New Technology for Construction of Cities in Mountain Area,Ministry of Education,Chongqing University,Chongqing 400045,China;National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas(Chongqing)Chongqing 400045,China;Hubei Key Laboratory of Geo-Environmental Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China;Communications New Technology Development Company of Shanxi Province,Taiyuan 030000,China)

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]山地城镇建设与新技术教育部重点实验室(重庆大学),重庆400045 [3]库区环境地质灾害防治国家地方联合工程研究中心(重庆),重庆400045 [4]中国科学院武汉岩土力学研究所环境岩土工程湖北省重点实验室,武汉430071 [5]山西省交通新技术发展有限公司,太原030000

出　　处：《成都理工大学学报（自然科学版）》2024年第5期833-844,853,共13页Journal of Chengdu University of Technology: Science & Technology Edition

基　　金：国家自然科学基金项目(52279094,41972316);重庆市自然科学基金(CSTB2023NSCQ-MSX0069)。

摘　　要：三维粗糙裂隙渗流换热机理的研究,对提升地下热储层的热提取率意义重大。当前,热开采过程中的多场耦合问题已取得了丰富的成果,但热开采过程中流体的相变作用对裂隙渗流特性及传热变化的影响却鲜有涉及。为剖析流体相变作用下的非线性渗流换热机理,以三维粗糙裂隙为研究对象,基于Fluent软件建立单相与多相流-热耦合模型,对比是否考虑相变作用的不同入口流速、入口温度和壁面温度时的局部换热系数分布特征。结果表明未考虑相变作用时,壁面局部粗糙程度控制局部换热系数的分布特征;基于Forchheimer公式,得知流体传热过程中非线性渗流特性显著。考虑相变作用后,流体呈现类似剪切稀释流体的特征,而气相体积分数则对系统换热过程起主导作用。因此,考虑流体的相变效应可以更准确地揭示热开采过程中的渗流特征和热提取效率的演化机理。Research on seepage and the law of heat transfer in three-dimensional(3D)rough fractures is important to improve the rate of heat extraction from underground thermal reservoirs.Although substantial progress has been made in addressing the multi-field problem of coupling encountered in the current process of thermal recovery,the effect of the phase transition on seepage and heat transfer through fractures has rarely been investigated.This study uses Fluent software to establish single-phase and multi-phase models of coupling of heat flow to analyze the nonlinear flow and mechanism of heat transfer in 3D rough fractures under the influence of the phase transition of the fluid.The numerical results showed that the local roughness of the rough fracture surface controlled the distribution of the coefficient of local heat transfer when the phase transition of the fluid was not considered.Moreover,the results of the Forchheimer formula showed that the heat transfer of the fluid significantly influenced nonlinear seepage through the fractures.When its phase transition was considered,the fluid exhibited characteristics similar to that of a shear diluted fluid,and the volume percentage of gas played a dominant role in heat transfer.This shows that considering the phase transition of the fluid can reveal the accurate characteristics of seepage and the law of evolution of the efficiency of heat extraction during thermal recovery.

关 键 词：粗糙裂隙 渗流换热 流热耦合 非线性渗流 相变 

分 类 号：P314[天文地球—固体地球物理学]