混凝土辐射供冷RC简化传热模型的改进及实验验证

Improvement and Experimental Validation of Modified RC-Network Model for Concrete Core Cooling Slab

混凝土辐射供冷非稳态传热过程的研究,对系统的运行和控制具有重要意义.本文对以系统几何及热工参数来确定核心温度层热容热阻的RC简化模型进行研究,加入沿管道供水换热过程的模型,实现供水温度和流量联合变化工况下楼板动态热响应的模拟分析.搭建混凝土辐射供冷系统全尺寸标准测试舱,验证上述模型的准确性和适用性.结果表明,在供水温度和流量非连续变化的非稳态工况下,模型计算值与实测值变化趋势基本一致,热流密度模拟值与实测值偏差约为5,W/m2,内部温度模拟值与实测值偏差小于等于0.5,℃,模拟误差小,适用性较高.

The unsteady heat transfer of concrete core cooling is of great significance in the operation and control of the system. In this paper, RC-network method is adopted to realize the optimization research, in which thermal ca- pacity and resistance of core temperature layer are determined with geometric and thermal parameters, the model of heat transfer process is added along the water supply pipe, and the simulation analysis is made of the dynamic ther- mal response of the floor under the combined change of water temperature and flow. In order to validate the model above, a full size standard test chamber of the concrete radiant cooling system is constructed. The result indicates that the simulation has good coincidence with the measurement in tendency under the unsteady condition of non-sequence change of supply water temperature and flow rate. The deviation of heat-flow density between simulation and meas- urement is about 5 W/m^2, and the deviation of inside temperature is no more than 0.5 ℃. The simulation error is small and applicability is high.