Flow and heat transfer characteristics of new-type hydrocarbon fuel at supercritical pressure conditions

This paper focuses on a new type high-specific-heat hydrocarbon fuel， designated as RP-3N， utilizing the Reynolds-Averaged Navier-Stokes （RANS） method to numerically analyse the turbulent flow and heat transfer characteristics of RP-3N at supercritical pressure conditions within an axisymmetric circular tube. The impacts of fuel type， wall heat flux， mass flow rate， inlet temperature， and inlet pressure on flow and heat transfer characteristics have been systematically evaluated through parametric variations at the inlet or wall. Computational results indicate that RP-3N demonstrates reduced flow resistance and markedly improved heat transfer efficiency compared to conventional RP-3 aviation kerosene， with the Nusselt number enhancement exceeding 17% at equivalent conditions. Increases in wall heat flux and mass flow rate significantly augment heat transfer intensity， with the former elevating the Nusselt number by approximately 42.67% and the latter by 96.56%. Although elevating the inlet temperature effectively intensifies convective heat transfer， it concurrently raises the average temperature of the cooling channel， thereby affecting thermal protection capacity. Furthermore， the study reveals that inlet pressure exerts negligible influence on flow and heat transfer performance at specific heat flux and flow rate conditions.