一种新模型的热力学描述:采用新鲜空气预冷和除湿的地板辐射供冷

摘要

A comfortable living space requires not only specific temperature but also fresh air with specific humidity.The thermal load of the space includes heat transfer through building envelope and energy change in ventilation.A new air-conditioning model,radiant floor cooling with fresh air precooling and dehumidifying,was constructed to provide the thermal load.Cycling water first exchanges heat in the radiant floor to control temperature,then continues to exchange heat with incoming fresh air before returning.The outlet temperature and mass flow rate of cycling water and exergy efficiency were analytically determined from energy and exergy equations for a specified thermal load.Analytical comparison with the conventional radiant floor method shows that this new model has lower outlet temperature and less mass flow rate of cycling water,and with higher exergy efficiency.The low outlet temperature and small mass flow rate could result in low investment and low operational cost.%一个舒适的居住空间不仅需要合适的温度,还需要有一定湿度的新鲜空气.空间的热负荷包括通过墙壁的换热和以通风方式进行的能量转变.构建了一种新的空气调节模型可以平衡空间的热负荷,即采用新鲜空气预冷和除湿的地板辐射供冷.循环水在一个循环周期内先后与辐射地板和进入空间的新鲜空气进行换热,与辐射地板的换热可以控制温度.循环水的出口温度、质量流率和(火用)效率可通过能量方程和(火用)方程进行分析确定,进而可以得出空间的热负荷.通过与传统辐射地板的计算分析比较表明:这种新模型具有较低的循环水出口温度、较低的循环水质量流率和较高的(火用)效率.而降低出口温度和质量流率可以节省初期投资和运行成本.