Study on the Performance Enhancement of Multichannel Flat Plate Heat Exchanger With Rectangular Winglet Longitudinal Vortex Generators

ABSTRACT This study concentrated on optimizing the performance of flat plate heat exchangers within heat recovery systems. A numerical simulation was conducted to investigate the effects of varying the number of channels and incorporating rectangular winglet longitudinal vortex generators on heat transfer performance. The findings revealed that the increase in the number of channels substantially augmented turbulence intensity, particularly enhancing reflow at the channel corners, thereby improving heat transfer efficiency while also elevating resistance. Relative to the single‐channel configuration, the Performance Evaluation Coefficient ( PEC ) values for the three‐channel and five‐channel configurations rose by approximately 44% and 28%, respectively. Moreover, the introduction of rectangular winglet vortex generators effectively disrupted the laminar boundary layer within the channels, thereby increasing local fluid turbulence. The optimal configuration of rectangular winglets can result in superior overall heat transfer performance compared with smooth channels. Specifically, a three‐channel system equipped with four rectangular winglets achieved a maximum increase in the performance evaluation criterion ( PEC ) of 12%. These findings underscore the crucial influence of channel quantity and longitudinal vortex generators in augmenting overall heat transfer efficiency, thereby offering valuable insights for the design and enhancement of heat exchangers.