The vibration relaxation time of CO₂ (ν₄ mode) and dissociation rate constant are obtained by the 4.3 and 2.7μ infrared emission in wider region of temperature than the experimental data which have been published already.
Some new conclusions can be made from these measurements, i.e.,
1) All four normal modes of vibration are coupled at the temperature range of 500° to 5, 000°K.
2) At the temperature over 6, 000°K, dissociation rate constant, kdA was obtained by DAVIES, but his results were the ones by the reflected shock waves. Present results by the incident shock waves are obtained up to 8, 000°K, and show slight difference from DAVIES' ones.
3) ARRHENIUS plots of dissociation rate constants at the temperature range of 3, 000° to 8, 000°K show the decrement of the activation energy at the higher temperature. The mean value of the activation energy of this measurement is 87 kcal/mole, which is higher than the value of DAVIES' or STEINBERG's experiment.
4) The efficiency of CO2 as the third body in the CO2 dissociation reaction is obtained. At the temperature of 3, 000° to 3, 800°K, k_dCO₂/k_dA is approximately 2.5-4.5.

View full abstract

This paper reports on wind-tunnel studies of wave riders which might form the basis of future hypersonic aircraft. Eleven kinds of models are tested such as simple caret wings, halved MAIKAPAR bodies and some special configurations.
Lift and Drag coefficients, Lift-Drag ratios, shock shapes and pressure distributions are measured using the Kyoto University new hypersonic gun tunnel.
Furthermore, the experimentally obtained data are compared with the theoretical value calculated by two dimensional theory.

View full abstract

As a fundamental study for the flutter analysis of swept-back wings, the vibration characteristics of a cantilever parallelogram box beam are analytically and experimentally studied. The fundamental equations are the same as those in the author's previous paper on the static deformation. Under the condition of large aspect ratio, the first approximation leads to the beam theory and the St. VENANT torsion theory for the natural frequencies and yields coupling between bending and torsion for the normal modes of vibration. For the second approximation of the natural frequencies, the effect of the shear deformation of the spar webs is treated in the bending vibration and the effect of the constraining of the warping at the root is treated in the torsional vibration. An experiment has been carried out on a specimen of the aspect ratio 7.5 and the swept-back angleof 30 degrees. Good agreement is found between the analytical values and the experimental results for both the natural frequencies and the normal modes.

View full abstract