摘要
地铁隧道围岩层的吸热与放热对改善隧道内热环境有直接影响,隧道内空气与近壁面岩层之间的温度差决定了吸热或放热能力的强弱,为此需要研究隧道围岩层温度场的变化。考虑到地铁在日间运营时列车会向隧道散热,到了夜间停运时隧道内无热量释放也没有空气流动,把隧道内列车的产热看作一个间歇性动作,同时空气与壁面之间的对流换热也是间歇性的传热。将隧道围岩层的传热简化为一维的非稳态导热模型,用ANSYS软件模拟二维的隧道围岩层温度场的全年动态变化。模拟结果显示,围岩层温度场变化呈年周期性,并通过组图描述热围岩层内热影响厚度的动态变化。
Heat sink effect of surrounding rocks has a direct impact on the improvement of thermal environment of subway tunnel,the differences of temperature between tunnel air and wall surface determine the validity of the heat sink effect,so it is important to study the temperature field of tunnel surrounding rock.In considering the subway operation schedule,the trains will release heat to tunnel in the running,but at night there will be neither heat releasing nor air flowing in tunnel,so heat produced by subway trains in the tunnel could be taken as an intermittent process,while the convective heat transfer between tunnel air and the wall surface is also an intermittent process.In this research,the heat transfer in rocks is simplified as one dimensional unsteady heat conduction model,ANSYS software is used to simulate the annually dynamic changes of two-dimensional temperature field in tunnel surrounding rocks.The simulation result shows that the temperature field in surrounding rocks is changed in annual periodicity,and through the pictures of temperature field,different heat transfer ranges of rocks surrounding the tunnel in different times could be described.
出处
《城市轨道交通研究》
北大核心
2014年第8期15-19,共5页
Urban Mass Transit
基金
国家自然科学基金项目(50908147)
上海市教委重点学科项目(J50502)
关键词
地铁隧道
围岩层温度
动态模拟
热影响厚度
subway tunnel
temperature of surrounding rocks
dynamic simulation
heat transfer range
