Investigations on the maximum limit of the circulatory lift for the conventional wing with the high aspect ratio have already been published in several papers, however, the analyses in those papers are limited almost to the case of the elliptical circulation distribution along the wing span. In this paper, the aerodynamic forces on the wing are analyzed theoretically for the cases of the various spanwise circulation distributions, not to mention the elliptical form, by using a proper form function, and the effects of the distribution form on the maximum limit value of the lift, the lift/drag ratio, and so on, are investigated. Moreover, in connection with these problems, this paper deals with the theoretical analyses concerning the structures of a pair of rolling up vortices with the cores existing in the infinite distance behind the wing. The results obtained in the present paper may be used as the available data for the investigation of the lift augmentation of the short take-off and landing airplane.
A numerical analysis has been made for the ionized reacting, thermal nonequilibrium boundary layer which develops along a shock-tube side-wall, behind an ionizing incident shock wave. The boundary layer flow has been found to change according to the ionization relaxation of the inviscid flow behind the shock wave. It has been shown that the temperature in the boundary layer becomes higher than that outside of the boundary layer in the rapidly ionizing region behind the shock wave. The numerical solutions were obtained for the case of the incident shock Mach number Ms=13, initial pressure p1=10 torr and initial temperature T1=300°K.
Electric potential technique was applied for determining the size of crack which was initiated and propagating under an impulsive loading. Calibration curve for crack size vs. potential change can be obtained by finite element method or simulating crack growth with a razor on duplicated aluminium foil specimen. The measurement of the electric potential across the crack was made by an oscilloscope. Some commercial 2V batteries was used for the constant current sources. Dynamic crack propagation was followed in the specimens of stainless steel and 7075-T6 aluminium alloy. It is worth noting that the maximum crack velocity in aluminium specimen was affected by the stress rate.