Conjugate heat transfer investigation of cooled turbine using the preconditioned density-based algorithm

The preconditioned density-based conjugate heat transfer (CHT) algorithm was used to investigate the heat transfer characteristics of a cooled turbine vane. Fluid domain provided boundary heat flux for solid domain and obtained boundary temperature from it for the coupling strategy. The governing equations were solved by the preconditioned density-based finite-volume method, with preconditioning matrix, improved Abu-Gharmam Shaw (AGS) transition model, matrix dissipation scheme and four kinds of turbulence models. The grid system is multi-block structured grids for fluid domain and unstructured grids for solid domain, with full-matched grids at the fluid–solid interfaces. The effects of turbulence model, outlet Mach number, outlet Reynolds number, inlet turbulence intensity and the temperature ratio of blade surface/gas on the local heat transfer performance were studied. Results indicate that the k–ω shear-stress transport (SST) and AGS model can predict the conjugate heat transfer better than others. The Mach number and Reynolds number have relatively obvious influences on the heat transfer, while the turbulence intensity and temperature ratio only have slight influences. Comparisons with experimental data demonstrate the applicability and accuracy of the numerical algorithm.