寒区隧道地源热泵供热系统及优化分析

为解决寒区隧道冻害问题,将地源热泵型供热系统应用于内蒙古博牙高速林场隧道中.系统由取热段、加热段、热泵和分、集水管路组成,可用于隧道洞口段衬砌和排水系统加热.在分析研究该系统传热机理的基础上,建立考虑热阻和热源的隧道取热段传热模型,利用叠加原理、格林函数法和拉普拉斯变换法相结合的方法获得其解析解.热交换管间距对热交换管换热量有显著影响,随着管间距的增加,换热量呈线性增加.热交换管换热量随隧道埋深的增加而呈线性增加,热交换管应布置在埋深深的部位.与热泵持续运行相比,间歇运行有利于土壤温度场的恢复,有助于提高热泵运行效率.

Tunnel Heating System with Heat Pump in Cold Region and Its Optimization

Tunnel heating system with heat pump was introduced for the first time at Linchang tunnel in Inner Mongolia Autonomous Region of China to prevent freezing damage in cold regions tunnels.Tunnel heating system consists of the heating section,absorbing section,heat pump,collector,and distributor line.This system can be used for heating lining and drainage system in tunnel portal.The heat transfer model of absorber pipes is obtained by considering thermal resistance and heat generation.The analytical solution can be obtained with the Green’s function method and Laplace transform technique.The distance of heat exchanger pipe has a great influence on specific energy output.With larger absorber pipes distance,the specific energy output of surrounding rock will increase linearly.The higher the ground temperature is,the greater the specific energy output of absorber pipes is.it is beneficial that the heat exchanger pipes should be placed in deeper depth of surrounding rock.Discontinuous operation of heat pump is good for the recover of soil temperature field around the heat exchanger pipes.Temperature increment between discontinuous and continuous operation presents an upward trend.Discontinuous operation is helpful to improve the coefficient of performance(COP) of heat pump.