Unsteady modeling of particle deposition effects on aerodynamics and heat transfer in turbine stator passages with mesh morphing

In order to have a further insight into the dynamic build-up process of particle deposits within the high-pressure turbine stator of an aeroengine and also into their effects on aerodynamic performance and heat transfer characteristics of the entire cascade passages, unsteady simulations coupled with a particle-wall interaction model and a dynamic mesh update technology were conducted in this study. The changing tendencies of flow field structures, aerodynamic losses, and heat transfer coefficients were characterized as the deposits on the stator increased with the exposure time. Results reveal that localized deposits with peak-to-valley patterns are generated with the accumulation of particles. The flow path area of the turbine passage is reduced due to the deposits that are mainly concentrated on the pressure side of the stator vane. Energy dissipation is generated as the mainstream gas flows through the fouled stator, which results in the deterioration of aerodynamic performance. Heat transfer presents a different tendency at specific locations on the vane surface with the dynamic deposition. At the early stage of deposition, slight deposits can reduce the thermal load on the vane to a certain extent, while as particles further build up, the heat transfer coefficient of the entire vane surface increases rapidly.