EFFECT OF A DELTA-WINGLET VORTEX GENERATOR ON THE PERFORMANCE OF A FIN-AND-TUBE HEAT EXCHANGER

摘要

The aim of this current work is to investigate a Delta-Winglet vortex generator to enhance heat transfer and reduce pressure drop of a fin-and-tube heat exchanger.Three patterns of fin including plate,louver and Delta-Winglet vortex generator geometry were examined in this study.The effect of a Delta-Winglet vortex generator on the performance of a fin-and-tube heat exchanger is experimentally investigated through full-scale wind-tunnel testing of a fin-and-tube heat exchanger under dry-surface conditions.Three types of heat exchangers including 1-row,2-row and 4-row with plate fin,louver fin and Delta-Winglet vortex generator (VG fin) were tested through different velocity conditions.The heat transfer rate per pumping power is assessed for a plate fin baseline、louver fin and for VG fin heat exchanger.For VG fin 1-row heat exchanger,heat transfer rate per pumping power increase over the baseline case of 20％ at a frontal velocity of 1 m/s,and approach the baseline case at a frontal velocity of 2 m/s.For VG fin 2-row heat exchanger,heat transfer rate per pumping power decrease over the baseline case of 15％ at full range frontal velocity.The frontal velocity ranges from 2 m/s to 5 m/s,the heat transfer rate per pumping power of plate fin heat exchanger is better than other sample.