There is the concept of adaptive-wall wind tunnel to reduce aerodynamic interferences between an airfoil model and tunnel walls. The figure control of solid wall and the pressure control at ventilated straight wall are technically useful controls as it is well known. A velocity control of closs-flow at the ventilated wall is considered to be technically useful. This paper presents numerical simulations of a transpiration velocity control at the ventilated two-dimensional adaptive-wall.
Both wind tunnel inner flow and outer flow are calculated simultaneously and independently on basis Euler equations using a finite difference method in Cartesian grid. The inner flow and outer flow are matched by pressure and flow direction at both sides of ventilated. straight wall. Numerical wind tunnel tests of NACA0012 airfoil is performed to demonstrate potentialities of the adaptive-wall control. Several calculated results of airfoil abilities in the numerical wind tunnel are compared with experimental and another calculated results.

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The supersonic mixing control is one of the key technology for developing scramjet engines (for future hypersonic vehicles), where the mixing and combustion of hydrogen and oxygen in a supersonic stream must be completed in a quite short period, e.g. lmsec. The present paper presents the main results of our experimental study on the supersonic mixing enhancement using streamwise vortices. Two kinds of models of strut-type are used to introduce counter-rotating or co-rotating streamwise vortices into their wakes in the form of a spanwise-row. The mainstream is set at a Mach number 2.4. A number of schlieren photographs, pitot pressure surveys and hot-wire observations show the development of small scale turbulent structures within the streamwise vortices, their strong interactions between themselves or with the shear layers from model surfaces, and their resulting breakdown. Compared with the counter-rotation case, the breakdown undergoes faster in the corotating case, where hot-wire measurements show that the rms fluctuation of local massflux can be as high as 10 to 30 % of the freestream value. Those results are discussed in view of the supersonic mixing enhancement.

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Experimental investigation reported here is concerned with instabilities appearing in three-dimensional laminar (Ekman) boundary layer flow. Ekman flow is produced in between two coaxial systems, one is a rotating cylindrical vessel filled with water, and another is a stationary disk mounted in the bottom of the vessel. Appearing instabilities in the boundary layer is visualized by introducing dye from narrow slits grooved on the stationary disk. In previous investigations, two types of instabilities were reported to appear, one, which appears at lower Reynolds number range was called Type II instability, and another, which appears at higher Reynolds number range was called Type I instability. In the present investigation, only Type I instability is observed. One of the important results obtained in the present investigation is that new types of stationary vortices are visualized in the boundary layer.

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