高温壁面条件下冷却液膜传热特性的数值分析OA

To explore the film cooling performance of low-thrust liquid rocket engines under high-temperature wall conditions,this study develops a three-dimensional CFD model that couples solid heat conduction,gas-liquid interface deformation,and multiphase phase-change processes.The model captures key behaviors of the liquid film,including impingement,spreading,evaporation,and boiling,using a VOF-level set interface tracking method and Lee phase-change formulation.Numerical results indicate that increasing the initial wall temperature significantly accelerates phase-change intensity,leading to transitions in boiling regimes.This results in a nonlinear reduction of cooling area and in extreme cases,the formation of a continuous vapor layer,which causes local cooling failure.In contrast,increasing jet velocity enhances liquid momentum,promotes film spreading,and strengthens convective heat transfer,thereby alleviating cooling degradation to some extent.A response surface model based on Weber number and dimensionless cooling area(R2=0.986 4)is constructed to quantify the coupled influence of wall temperature and momentum input,successfully identifying cooling effectiveness boundaries.Additionally,the film demonstrates strong spatial heterogeneity,with the impingement region showing the highest heat transfer efficiency,while downstream areas are limited by unstable boiling dynamics.