A FAST-RESPONSE TOTAL TEMPERATURE PROBE FOR UNSTEADY COMPRESSIBLE FLOWS

A fast-response probe for the measurement of total temperature in unst eady or fluctuating compressible flows is discussed The operation of t he device is based on the measurement of transient heat flux at differ ent probe operating temperatures. The heat flux gauges used in the pre sent investigation were thin film platinum resistance thermometers pai nted onto the stagnation region of hemispherical fused quartz probes. The quartz probes had a diameter of approximately 3 mm. Uncertainty es timates indicate that temperature measurements with an accuracy of bet ter than +/-3 K are possible. As a demonstration of the accuracy and u tility of the device, total temperature and convective heat transfer c oefficient measurements were obtained in a number of supersonic nozzle tests and in a compressible turbulent jet experiment.