Convection/Film-Cooled Leading Edge for NASP

NASP 2nd Generation Prototypes

In 1991 Micro Cooling Concepts' employees completed a Phase I SBIR contract to develop a prototype leading edge for a NASP-class hypersonic vehicle. This leading edge represented the second generation of our leading edges, using an innovative combination of film and internal cooling during the nominal heating portion of the trajectory, and using micro-nozzles to blow off the bow shock during shock-on-lip encounters. The program served as a foundation for 3rd generation leading edges constructed under NASA/Langley sponsorship in 1995.

Two models were constructed during the 6 month program, as shown in the photograph above. There are three coolant lines running into each model: one was for the film cooling circuit, and the second and third were for the forced convection cooling circuit inlet and outlet. The models themselves were approximately 2" x 2", with an effective nose radius of 0.125", and a wedge half angle of 5 degrees.

The photograph above shows a closeup of the face of one of the models. The four rows of film cooling slots can be seen on the flat face. The rows are staggered to assure that the down stream "lands" between cooling slots are cooled by upstream slots. The slots themselves are approximately 50 microns high and 750 microns wide.

The models were delivered to NASA/Langley for wind tunnel testing, where they were successfully used in a series of shock interaction tests.