Applications of infrared thermography in a hypersonic blowdown wind tunnel

The authors describe special applications of infrared imaging for the measurement of the surface temperature distribution on models exposed to a hypersonic flow field. A number of infrared images are shown, which demonstrate the advantages and limitations of this measurement technique. In connection with image processing of an IBM computer the infrared thermovision proves to be a powerful tool for obtaining a quick survey of the surface temperature distribution on wind-tunnel models. Due to the high framing rate of the camera system used, it is possible to calculate the time-dependent heat flux from the flow to the model surface from the recorded temperature data. All the examples are taken from experiments carried out with different kinds of models at the H2K blowdown facility in Cologne