Design and Evaluation of a Single Passage Test Model to Obtain Turbine Airfoil Film Cooling Effectiveness Data Free

A single passage test model has been designed to simulate the mainstream aerodynamics between two adjacent turbine airfoils and to measure the film cooling effectiveness from coolant injection on the pressure and suction sides of the airfoils. Film cooling tests were run on the model using a gas concentration/mass transfer technique with a foreign gas as the coolant to match density ratio. Aspects of the design and test are discussed including the use of a two-dimensional inviscid flow analysis to design boundary layer bleeds upstream of the pressure- and suction-side airfoil surfaces. Results of two- and three-dimensional viscous flow analyses that were used to evaluate various design features including inlet bellmouth, boundary layer bleeds, adjustable tailboards and model backpressure are presented. Aerodynamic and film cooling effectiveness test measurements made with the model will show that the model flow field can be controlled to match results from a previous thermal cascade test.