註釋 Abstract: An experimental film cooling study was performed to understand heat transfer effects due to upstream synfuel deposition. A scaled up model incorporating actual synfuel deposition topography was used. The model contained six cylindrical holes inclined at 30°. A flat model with the same film cooling hole geometry was used for comparison. An infrared camera was used to obtain both the film cooling effectiveness from a steady state test and heat transfer coefficient from a transient test. The roughness model had deposition valleys along the centerline of the holes, which caused the flow to accelerate around the peaks and helped to keep the coolant jet down on the surface. This flow acceleration caused large film cooling effectiveness improvements for the 1 and 1.5 blowing ratio cases. The heat transfer coefficient showed both cooling benefits as well as cooling losses due to deposit roughness. The roughness model showed no kidney vortices as opposed to the flat model, which produced a beneficial localized reduction in heat transfer coefficient around the film cooling holes. Although a sharp detrimental rise in heat transfer coefficient occurred on the rough model for the 1.5 blowing ratio case. The heat flux ratio shows the overall cooling effect and a substantial cooling benefit compared to the flat model occurred at blowing ratios of 1 and 1.5. It is concluded that the film cooling effects of upstream deposition on actual turbine blades can be highly beneficial. 