Leading edge cooling by upstream injection

A leading edge cooling system by upstream along the surface was investigated. The purpose of this system is to keep the leading edge below a desired temperature without excessively increasing the radius of the tip and consequently the total pressure losses. An experimental investigation was conducted to find the optimum conditions for the cooling from the point of view of upstream jet penetration and minimum shock losses. A theoretical analysis was performed to study the flow field in the mixing region between the two counterflowing streams and the results obtained compare favorably with the experimental results.