A Numerical Study on Swirling Hot Air Anti-Icing with Various Surface Structures on the Internal Wall

Swirling hot air is a promising heat transfer enhancement technology for anti-icing applications in aircrafts, where the swirling flow accompanied by pretty high turbulence and quite thin boundary layer. It of interest to investigate compound characteristics configuration combined with surface structures on internal wall. This paper carries out series numerical computations obtain Nusselt number pressure loss data such system four kinds (trenches, ribs, dimples bulges) wall different tangential inlet jets placed along tube. At tube Reynolds from 10,000 50,000, results show that bulges are conducive improving number, but trenches ribs deterioration relative smooth swirl Among investigated structures, perform best, which can enhance up 15.0%, increase total quantity 17.3% reduce 15.6%. Furthermore, circumferential velocity distribution introduced describe fields. The lead less reduction intensity, while could significantly suppress in-tube intensity.