Effects of Circumferential and Longitudinal Ribs and Grooves in Swirl Cooling on Characteristics of Pressure Drop and Heat Transfer

Abstract

AbstractThe impact of roughened swirl cooling chamber walls on heat transfer and fluid flow characteristics is explored in this study. This study compares ten roughened wall shapes against a smooth wall in a swirl cooling chamber. The roughened wall shapes are circumferential and longitudinal with and without cuts. The circumferential cases consist of four cases. The first case, designated as a circumferential groove (CG), contains eight grooves along the surface. The second case, designated as a circumferential groove cut (CGC), has eight cut grooves along the surface. The third case is called a circumferential rib (CR), and the fourth case is called a circumferential rib cut (CRC), and it has eight ribs without and with surface cuts. While the longitudinal cases consist of six cases. The first four cases, which have six longitudinal grooves and ribs with and without cuts, are longitudinal groove (LG), longitudinal groove cut (LGC), longitudinal rib (LR), and longitudinal rib cut (LRGC). The final two longitudinal cases, longitudinal rib groove (LRG) and  Longitudinal rib and groove cut (LRGC), have hybrid grooves and ribs without and with surface cuts. Bulk temperature averaged circumferential heat transfer ratio, friction factor, global thermal performance factor, and turbulent kinetic energy are among the variables that were examined. Simulations are performed using CFD codes. These examined parameters are contrasted with results from previous studies. The findings demonstrate that heat transfer is boosted by roughly 2.7, 2.6, and 2.5 times higher in cases with LG, CG, and CGC, respectively, than in the smooth case. The use of rough walls in the swirl cooling chamber boosts the global thermal performance factor; the LG case has a 2.8 times higher global thermal performance factor than a smooth case. In comparison with alternative internal cooling technologies, a grooved wall, as shown in the LG case, has the best heat transfer characteristics.