Numerical study on jet impingement boiling cooling of nose cone

Abstract

This study presents a numerical analysis of confined water jet impingement boiling on the nose cone of a hypersonic aircraft subjected to extreme aerodynamic thermal conditions. The investigation addressed impingement boiling cooling within a non-uniform aerodynamic heat environment and over a curved impinged surface, leading to highly complex flow and boiling heat transfer characteristics. To manage these complexities, external aerodynamic heating, thermal conduction, and jet impingement boiling were quasi-coupled within a unified mathematical model. The multiphase flow and heat transfer within the nose cone were analyzed across different flight speeds and jet Reynolds numbers. The results showed that water impingement boiling cooling effectively reduced surface temperatures at relatively low Reynolds numbers. Increasing the Reynolds number had minimal impact on the vertex temperature but reduced the overall heated surface temperature of the nose cone. The curved design of the impinged surface generated two high-performance heat transfer regions: one dominated by boiling heat transfer and the other by single-phase convective heat transfer. The heat transfer capacity in the boiling region was dependent on flight speed, whereas in the single-phase region, it correlated with the Reynolds number. Based on these findings, recommendations for optimal Reynolds number requirements at various flight speeds are provided to ensure effective local temperature control at the curved section of the nose cone.