Pressure sensitive paint (PSP) is an optical tool that detects Oxygen concentration over a PSP coated surface. This non-intrusive measurement technique is used to study the effect of film cooling over an airfoil by including a foreign gas, compressed Nitrogen in this case, in the coolant feed. An in-situ calibration method has been developed for the PSP. The data from experiments is gathered using monochromatic cameras with a good resolution and high SNR for flow feature resolution, while a low frame rate is sufficient to log the steady state phenomena. Each film cooling design is examined over a range of coolant mass flow rates (set using accurate mass flow controllers), under almost identical mainstream flow conditions.
The facility also has provision to perform heated-flow experiments through a heater mesh connected to the drake power supply.