Study on thermal coupling method of deposit particle layer with blade wall in a turbine cascade

With particle deposition in a turbine cascade, the particles build up and form a thin layer attached to the blade wall. The presence of the particle layer alters the heat transfer pattern through the boundary. In this study, a gas-solid-solid transient heat transfer model (referred to as the 3D/1D/3D model) is proposed, which accounts for the effect of the deposited particle layer on the thermal boundary. Heat transfer through the layer is computed using the 1D heat transfer equation instead of redividing the computational mesh for the deposit layer or using the mesh morphing technique. The effects of three particle sizes (3, 8, and 13 µm) and three inlet temperatures (1456, 1556, and 1656 K) on particle deposition and heat transfer have been investigated. The results show that the presence of the particle deposit layer significantly alters the heat transfer pattern on the blade wall. This alteration can either enhance or weaken heat transfer, depending on both the height of the deposit layer and the flow pattern at different locations along the blade.