The effect of magnetic fields (up to 15, 000 Gauss) on probe measurements in weakly ionized argon plasma flow (the charged particle density-109cm-3) at one atmospheric pressure produced using the arc discharge was experimentally investigated. The probe is so placed that its surface is parallel with or perpendicular to the magnetic field whose direction coincides with that of the plasma flow. It was found that the ion currents are hardly changed and the electron currents are greatly reduced by the magnetic field, even in the case of the perpendicularly placed probe as well as that of the probe placed in parallel. Besides, it was noticed. that the reduction ratios of the electron currents are in the same order of magnitude as the value of D⊥/D//, the ratio of the electron diffusion coefficient to the magnetic field-free electron diffusion coefficient.
This paper deals with the heat transfer in convergent-divergent nozzles. A differential equation is derived in order to determine the heat transfer rate as a function of nozzle geometry in the subsonic part, and one dimensional nozzle flow equations including heat transfer and frictional drag are used for the analysis in the supersonic part of nozzles. The validity of these processes rests with some favourable comparisons with measurements. The results are considered to be useful for the preliminary estimate of high enthalpy supersonic nozzle flow under the influence of heat transfer and frictional drag and the for the design of nozzles of minimum heat transfer. The need for fundamental knowledge of boundary layer in such internal flow field is increased in order to develop this kind of problem.
The supersonic panel flutter of circular cylindrical shells with clamped ends is studied analytically and experimentally for the case of no inplane stress as a fundamental study. Using the two-mode approach and GALERKIN'S method, the panel flutter boundary, frequency and circumferential mode are obtained in the linear theory. The longitudinally seamed cylinders with 110mm diameter, 110mm length and 0.05-0.08mm thickness were made of super-invar in order to avoid the effect of temperature variation. The static pressure differential between two surfaces of the shell was automatically controlled so as to be zero in order to avoid its effect. The cylinder was tested at Mach number 2. The dynamic pressure was gradually increased and the occurence of the panel flutter was clearly observed in the oscillograph of the deflection and the records of the high speed camera. A good agreement between the analysis and the experiment is obtained for the flutter boundary, but not obtained for the flutter mode and frequency.