EXPERIMENTAL SETUP ON TRANSPIRATION COOLING IN SUPERSONIC COMBUSTION RAMJETS (SCRAMJETS)

One of the main challenges for scramjet propulsion systems is the efficient and sufficient cooling of the engine’s components. A promising cooling approach could be the method of transpiration / effusion cooling, where the coolant flows through a porous wall prior to entering the engine’s main hot gas flow. This could establish a homogeneous and protective coolant layer at the engine wall, protecting the areas with high thermal loads and the engine structure from thermal damage. The Institute of Space Propulsion of the German Aerospace Center (DLR) has developed a research test bench to investigate the applicability of transpiration cooling systems to scramjets. This publication addresses the challenges connected with initial operation and summarizes the results of preliminary tests. Further research requirements are discussed.