深部能源开采中多场耦合模型研究现状——以干热岩为例

Research status of multi‑field coupling model in deep energy exploitation:A case study of hot dry rock

随着地球浅部能源资源的日益减少,人类逐步向深部能源开发转型,中国深部干热岩型地热资源具有巨大潜力,但开发研究尚处起步阶段,深部能源开采必然面临着高温、高应力、高渗透压力及水化学环境问题,因此岩石THMC(温度场+渗流场+力学场+化学场)多场耦合作用是当前研究的重点。本文介绍了多场耦合模型建立的方法及其发展过程,概述了多场耦合模型在深部能源开采中的应用,特别是增强型地热系统(Enhanced Geothermal System,EGS)中的多场耦合问题和相关试验研究,表明了EGS中的裂缝扩展、化学增产措施和力学参数研究是重点研究问题,强调了深部能源开发的紧迫性和必要性,为今后的研究和实践提供了重要的参考和指导。

With the decreasing of shallow energy resources of the earth and the gradual transformation to deep energy development,China’s hot dry rock geothermal resources have great potential,but the development and research is still in its infancy.Deep energy exploitation will inevitably face the problems of high temperature,high stress,high permeability pressure and hydrochemical environment.Therefore,the multi-field coupling effect of rock THMC(temperature field+seepage field+mechanical field+chemical field)is the focus of current research.In this paper,the method and development process of the multi-field coupling model are introduced,and the application in deep energy exploitation is summarized,especially the multi-field coupling problem in the Enhanced Geothermal System(EGS)and related experimental studies.The results show that the research on crack propagation,chemical stimulation measures and mechanical parameters in EGS is the key research problem.Moreover,the urgency and necessity of deep energy development are emphasized,which provides an important reference and guidance for future research and practice.