곡면 델타 윙렛 와류발생기를 이용한 핀 휜의 열전달 및 유동 특성 개선

Abstract

A numerical analysis was carried out to investigate the effects of curved delta winglet vortex generator on the heat transfer and flow characteristics of pin fin arrays. The steady RANS simulation has been performed with κ-ω SST turbulence model by using Fluent 18.0. The effects of the curved delta winglet vortex generators installed upstream of each pin of the staggered array 8 row pins were confirmed, and the cases where the curved delta winglet vortex generators were located on one endwall(Case 1) and on both endwalls(Case 2) were considered. The results showed that the curved delta winglet vortex generators induce the generation of mixed vortices that reduce the size of the wake region of the pin and improve the heat transfer of the pins. In addition, the pressure loss is reduced due to the effect of decreasing the size of wake occurring in the pin, and this tendency becomes stronger as the Reynolds number increases. As a result, the thermal performance factor(η) increases according to the Reynolds number, and when the Reynolds number is 30000, η of Case 1 and Case 2 increased by 11.3% and 12.2%, respectively, compared to the baseline.