Beschreibung
This work investigates the film cooling technique for surfaces exposed to high speed flow, as encountered on spacecraft and inside of rocket nozzles. A wide range of flow regimes is covered. Laminar flow, foreign gas injection, turbulent flow, hypersonic flow and cooling in a flow exposed to a pressure gradient were researched. Therefore, models with different slot openings for coolant injection were prepared and experiments were conducted at the hypersonic shock tunnel TH2 of the Shock Wave Laboratory. A comparison of different correlations for the cooling effciency reveal the main parameters influencing the cooling effect: The distance from the injection opening, the coolant mass flux and the main stream flow velocity and density. A verification with experimental results, as well as experimental and numerical data from literature has lead to an extended correlation for film cooling in laminar as well as turbulent flow.