Simulation of particle deposition on high temperature turbine film cooling blade surface with dynamic mesh morphing

Abstract

Particles carried by gas and impurities in the operation environment can deposit on turbine blades. The deposition of particles on high temperature turbine blade can seriously damage aerodynamic efficiency and cooling characteristic. Numerical simulations are utilized to investigate particle deposition and the influence of deposition on cooling performance of high temperature turbine blade. The Euler Lagrangian method is chosen to track particles. Firstly, a deposition model is developed to estimate particle deposition by User Defined Function (UDF) of Fluent. On the basis of it, dynamic mesh morphing is used to simulate the blade surface changes caused by deposition. It is mainly explored the differences in the number, thickness, and distribution of particle deposition with different particle sizes and blowing ratios. The effect of particle deposition on film cooling effectiveness is also taken into account. The result shows that particle deposition is more likely to occur at the leading edge of the blade and near the trailing edge of pressure side. Deposition on the pressure side near the leading edge can make a positive effect on cooling effectiveness. For different particle diameters, the deposition number of 10 μm particles is highest, the maximum deposit thickness of 20 μm even exceeds 2 mm. For different blowing ratios, the influence of particle deposition is mainly reflected in the middle of the pressure side. The cooling effectiveness loss can reach 30%.