基于 CFD-DEM 微细带肋内冷通道中颗粒沉积特性比较研究

When operating aero-engines under all-weather, all-region and long endurance conditions, particles enter the internal parts of turbine blades through the secondary flow air system. These particles deposite and block the internal cooling air system of gas turbines, significantly impeding the cooling performance of the turbine blades. A combination of computational fluid dynamics and discrete element method (CFD-DEM) was used to investigate the flow and deposition characteristics of fine dust particles in a miniature ribbed rectangular internal cooling channel of a turbine blade. The ribs were periodically arranged on one side of the channel, with a rib blockage ratio of 0. 024 and a rib spacing ratio of 10. Three rib structures, such as transverse rib, 45° inclined rib, 45° V — shaped rib were analyzed. The effect of Reynolds number, Stokes number, inlet particle volume fraction and rib layout on the particle flow and deposite characteristics was studied. Results show that particle deposition occurs mainly at the leading edge of the first rib ; the deposited mass of the particles all decrease with increasing Reynolds number, Stokes number and particle volume fraction ; in all different rib layouts, the transverse rib exhibits the highest deposition mass, followed by the V-shaped rib, while the inclined rib has the lowest deposition mass.