通风室内地板辐射供暖过程模拟与评价

Numerical Modeling and Evaluation Of Radiant Ground Heating In The Slot Vented Building Enclosure

采用k-ε湍流模型和DO辐射模型建立了室内带置换通风的地板辐射供暖系统的数学模型,数值模拟了侧送风、上送风和不带通风三种情况下的温度分布和速度分布,以及沿辐射地板和外墙上的辐射换热与对流换热的特性,分析了送风方式对室内空气流动和换热的影响。结果显示,室内平均温差在1℃范围内;不同送风方式下,室内空气流动呈现不同的规律;三种情况下沿地板和外墙上的换热过程均以辐射为主,室内辐射平均热流约占总热流的50-60%,其中上送风的比例最大,而三者的辐射强度差别不大;侧送风时沿地板和外墙上的对流换热能力最强。研究表明置换通风加强了对流换热,有利于改善室内的热舒适性。研究结果对地板辐射供暖技术和工程应用有重要意义。

A mathematical model of radiant floor heating with displacement ventilation in room was developed to simulate the indoor air flow and heat transfer based on the k -ε turbulent flow model and DO radiation model. The isotherms and flow patterns in room with and without displacement ventilation were compared. Furthermore, the heat transfer behaviours along the radiant floor and outer wall were obtained. The results show that the average temperature difference of indoor air is smaller than 1 ℃, and the indoor airflow shows the different behaviors un- der the different air supply. The radiation is the main mechanism for heat transfer along the floor and the wall. The radiation heat flux ac- counts for 50 -60 % of the total heat flux in the room, in which the ceiling air supply has the highest ratio but radiation intensive has the small difference between the three modes for air supply. The mean temperature in room with lateral supply air is higher than that without venti- lation but lower than that with ceiling air supply, which indicates that displacement ventilation is beneficial for improving indoor thermal com- fort by intensifying convection heat transfer. The results are greatly significant for the development and application of radiant floor heating.