新型辐射供冷末端装置性能的数值模拟

Numerical Simulation on Performance of a Novel Radiant Cooling Device

传统辐射供冷末端装置由于需要防止结露,冷表面最低温度受周围空气露点温度限制因而辐射供冷量有限。这大大限制了其在我国,特别是气候潮湿省份的推广应用。为解决这一问题,一般需增设额外的对流冷却装置,但这样既增加了系统复杂度和初投资,也无法完全体现辐射供冷的节能效果。本文设计了一种新型辐射供冷末端装置,无需增加其他辅助冷却系统,就可解决结露问题;并且本装置能够促使辐射冷量集中,进一步提升面向对象的供冷效果。为验证这一效果,本文通过计算流体动力学(Computational Fluid Dynamics,CFD)数值模拟的方法,在三维模型中考虑人体负荷,得出以人体体表温度作为表征供冷效果的重要指标。模拟结果验证了新型辐射供冷末端装置的局部供冷效果,为其完善与应用提供了参考与指导。

To avoid the condensation phenomenon,the lowest temperature of the radiant surface of a conventional radiant cooling devices has to be higher than the dew point of indoor air,leading to its limited radiant cooling capacity.It restricted the application of radiant cooling devices in China,especially in those provinces in humid weather.A possible way to deal with this issue is to add additional convective cooling devices,which however would increase both system complexity and initial investment,and deteriorate the energy saving performance of radiant cooling devices.In this study,a novel radiant cooling device is developed to solve the problem of condensation.It does not require any supplementary cooling system and is capable to enhance object oriented cooling performance by concentrating radiant cooling power.To test the effect of this new device,two 3 D models including mannequin have been constructed by CFD,in which skin temperature is regarded as an important criteria of cooling performance.The simulation results prove the excellent cooling performance of the novel radiant cooling device and provide the reference for its future improvement.