Ikuo Mabuchi

An Experimental Study on the Effectiveness of Adiabatic Plate Covered by Cold Air Film

Experimental results are presented for the effectiveness of film cooling of cold air film injected through a preceded porous section of a flat plate covered by fully established turbulent boundary layer and correlated with an empirical equation. Also, some considerations are made to distinguish the character in the effectiveness of tangential slit injection from that in the present partially porous injection

Heat Transfer of Liquid-Metal in Turbulent Flow on a Plate

This paper shows a theoretical analysis of the heat transfer to a liquid-metal flowing turblently on a flat plate. The construction of analysis is performed on the following assumption. (1) The velocity distribution in the boundary layer on a plate comforms to a new semitheoretical formula studied by Hama recently. (2) The physical properties of a liquid-metal are constant. (3) The turbulent boundary layer is divided into the viscosity layer and turbulent layer. The shearing stress and heat flow flux in the viscosity layer equal to those values at the plate surface. The distribution of shearing stress in turbulent layer is similar to one of the heat flow flux, and the heat flux transported through the sectional element vertically to the flow direction is proportional to the velocity at that place. (4) The molecular diffusion is considered at turbulent layer.

Laminar Free Convection from a Horizontal Plate with Uniform Surface Heat Flux

The partial differential equations expressing the conservation of momentum, mass, and energy for the laminar free convection from a horizontal flat plate, having a finite thickness and length, were transformed into the ordinary differential equations, which were obtained for both the upper and lcwer surfaces of a horizontal plate. Also, it was demonstrated that the ordinary equations for the upper surface were equal to those obtained for the vertical plate, having uniform heat flux studied by E.M. Sparrow, but the equations on the lower surface had the different forms. The distributions of local heat-transfer coefficient and surface-temperature variations on both the surfaces, by considering a plate whose cross section is of a very thin ellipse, were calculated by means of Runge-Kuttas and von Karman-Pohlhausens methods. It has been shown that the mean heat-transfer coefficient on the lower surface is affected by the thickness of the plate, and it is about 60% of that the vertical plate with same length, and that if mean Nusselt number for the plate with uniform surface heat flux is calculated by using the mean temperature difference over the surface, the results are very close to that for a uniform surface temperature plate.

Analytical Treatment of Two-Dimensional Laminar Jet in Compressible Fluids

The research of laminar jet in compressible fluids was dealt theoretically by Pai, Krzywoblocki, Illingworth etc., but they did not obtain analytical solution. Recently, Toose used the Karman-Tsien transformation in boundary layer flow theory and obtained analytical solution under some allowable assumptions, but t seems that his analytical method is difficult to be applied to axialey symmetrical jet, because he uses Karman-Tsien transformation. If we generalize the Bicklly transformation against the jet of the incompressible fluids, we are possible to solve either two dimensional or axially symmetrical jet of the incompressible fluids. In this paper, the author shows the analytical treatment of two dimensional laminar jet.