Detailed knowledge of the laminar-turbulent transition and the heat transfer distribution of flows around complex aerodynamic components are crucial for achieving maximum efficiency in modern aerodynamic systems. Supported by the joint program AG TURBO and MTU Aero Engines, a transient infrared measurement method is being developed that allows the non-contact and two-dimensional visualization of thermal transitions in boundary layers. Thereby, heat energy is deposited on the surface of an object by a short light pulse. The subsequent temperature decay is recorded with high temporal resolution with an infrared camera and a quantity proportional to the heat transfer is calculated. If the calculated value for each pixel is displayed, a qualitative heat transfer distribution results. By means of a suitable calibration, quantitative statements as well as qualitative progressions are to be made possible.
A great potential of the measurement method is the possible applicability in hard-to-reach and rotating systems to characterize flow, e. g. in turbines.
Person in charge: M.Sc. Stefan von Hößlin, MTU Aero Engines AG