Experimental study on the effect of tube surface modifications and in-channel baffle plates on falling film evaporator heat transfer properties for sever cabinets

To effectively alleviate the high energy consumption associated with traditional cooling strategies in data centers, this research synoptically designs an innovative and energy-efficient integrated structure combining a falling film evaporator with a cabinet. An experimental setup with a water film tube in a rectangular channel is constructed, and the impacts of liquid film temperature, spray density, and inlet air Reynolds number on heat transfer properties in the cases of the tube's surface structure modifications and baffle plates presence in the channel are explored, respectively. Two significant findings that enable low energy consumption-oriented cooling strategy development are derived. (1) Decreasing the spray density can reduce energy consumption when liquid film integrity is maintained. Upon quadrupling the inlet spray density for the smooth and finned tubes, the heat transfer rate and heat transfer coefficient between the tubes and airflow in the baffled and unbaffled channels only increase by 23.1 to 29.9% and 18.6 to 28.3%, respectively. (2) The tube surface modifications and baffles presence can significantly improve the heat transfer performance. The performance evaluation criterion between the airflow and finned tube in the channel with baffles is 2.5–4.0 times higher than those between the airflow and smooth tube in the baffle-free channel. •A novel integrated cooling cabinet structure is proposed.•A flow channel for studying the falling film heat transfer properties is designed.•The effect of tube surface modifications on heat transfer properties is studied.•The effect of baffle plates on heat transfer properties is investigated.