Inlet Design for Japhar Flight Test Vehicle

In the frame of JAPHAR project different inlet concepts were designed in order to feed a dual mode ramjet engine propelling a flight test vehicle between Mach 4 and 8 and burning Hydrogen as a fuel. The mixed compression inlets studied by DLR can be operated without bleeding and provide self starting capability at low Mach number, but, due to their high design Mach number (around 6) a large amount of flow spillage occurs at the lowest bound of the flight range. ONERA focused on internal compression inlets requiring bleeding and variable geometry to insure starting, but which could easily be operated with variable geometry to cover a wider Mach number range if necessary. The paper gives the most significant experimental results obtained in H2K (DLR) and S3MA (ONERA) wind tunnels and put the emphasis on CFD validations performed by ONERA on the isolated internal compression inlet