抄録
Shock tube generates heated gas by reflected shock near the end wall of the tube. The hot gas temperature, pressure, and density distribution is homogeneous, so the gas is used for heat transfer test, and reservoir gas for shock tunnels which can generate hypersonic flow. However, it is difficult to measure the temperature. Since the duration is very short: about lmsec. Thermocouple can't be used to measure the temperature, because the response time isn't enough. Therefore, in this paper, for instantaneous measurement, we used diode laser absorption technique. Chemical species (this time, water) absorb light. The theory is that the ratio of two-wavelength absorption band is function of only temperature. The result is the differences between theoretical values and measured values are large. It is thought that heat of evaporation deprive hot gas of heat.
