Experimental investigation of the impact of room/system design on mixed convection heat transfer

Night cooling attracts growing interest. However, architects and engineers still hesitate to apply night cooling because of the important but hard-to-predict convective heat transfer by night. Obviously, this heat transfer mechanism depends on the driving force, fluid motion and heat transfer surface and, thus, on the room and system design. Unfortunately, studies addressing this are scarce. In response, underlying experimental effort intends to instigate global parametric analyses of night cooling at room level. To this end, this study, held in a PASLINK cell, investigates how the ventilative cooling rate, thermal mass and the supply/exhaust configuration affect the convective heat transfer. The analysis is based on airflow data, such as temperature and velocity, and the related convective heat flux. The results indicate the need for an integrated room/system design. After all, the position of the supply relative to thermally massive elements predominates the night cooling performance.

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