Calibration of reaction temperatures in a very high pressure shock tube using chemical thermometers

Two chemical thermometers, 1,1,1-trifluoroethane and cyclohexene, have been used to calibrate the temperatures behind reflected shock waves, T-5real, in a unique high-pressure, single-pulse shock tube. Experiments with 1, 1,1 -trifluoroethane were performed at nominal postshock pressures of 5000 psi and 9000 psi, and T5real was calculated from the extent of the reaction and literature values for k(infinity) Both parent molecule decomposition and p roduct formation were used to calculate the extent of reaction. At each pre ssure the two methods of calculating T-5real are in excellent agreement, Th e values for T-5real obtained from the cyclohexene experiments are in good agreement with those from 1, 1, 1-trifluoroethane. The range of the temprat ure calibration is 1050-1350 K. No discernable pressure dependence between the two sets of experiments was observed for the calculated values of T-5re al The effect of a 10% rise in pressure during the residence time on the ca lculated temperatures was also examined and is found to give rise to only s mall errors in T-5real (C) 2001 John Wiley & Sons, Inc.