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Fluctuations of wall pressure and heat transfer rate have been measured in the regions of interaction between oblique incident shock waves and turbulent boundary layers. Experiments were made at a nominal Mach number of 4, and Reynolds number of 1.26×107 based on the distance from the leading edge of the flat plate, and under cold wall condition. When boundary layer is unseparated, fluctuations of wall pressure and heat transfer rate get strong near the impingement point of the incident shock wave, and no intermittency is observed. When boundary layer is separated, significant fluctuations of wall pressure and heat transfer rate are observed throughout the interaction region, particularly near the separation point and near the reattachment point. Near the separation point, remarkable intermittency is observed in the fluctuations of wall pressure and heat transfer rate.

A new method of measuring heat transfer rate with high spatial resolution and fast response is developed to be used in wind tunnels with long flow duration. For the development of the new method a multi-layered thin film heat transfer gauge is proposed. The principle of the sensor is based on measuring the temperature gradient across a thin, heat resistant layer of SiO with two, thin film resistance thermometers on its upper and lower surfaces. These thin films and the heat resistant layer are deposited by vacuum evaporation technique. The design consideration, the accuracy of the sensor, frequency response, and the calibration technique are discussed. The sensor is applied to the measurement of the heat transfer rate in turbulent boundary layer on a flat plate at Mach number 4, Tw/T0= 0.64, and Re=1.4×107, and shows high sensitivity and fast response. It also shows excellent durability.

A new type of thin film heat transfer gauge is applied to the measurements of heat-transfer coefficients in the interaction regions of oblique shock waves and fully developed turbulent boundary layers. It has been developed for the measurements of heat flux with high spatial resolution and fast response for wind tunnels with long flow duration. Experiments have been performed under the conditions of Mach number=4, total pressure=1.2MPa, Tw/T0=0.59-0.65, Reynolds number=1.3-1.5×107, and incident shock angles from 17.8 degrees to 22.8 degrees. Flow fields are visualized by the Schlieren technique. Both distributions of surface pressure and heat-transfer coefficient are measured throughout the interaction regions by scanning the shock generator parallel to the free stream. Owing to the high spatial resolution of the new sensor, complicated features of the aerodynamic heating in the interaction regions are revealed.