Aerodynamic interferences between an airfoil model and wind-tunnel walls cannot be avoided in the structure of wind-tunnel. There is the concept of adaptive-wall to reduce the previous interferences. This paper presents numerical simulations of streamlined adaptive-wall control for two-dimensional wind-tunnel. Numerical wind-tunnel inner flow past airfoil and outer flow are calculated simultaneously and independently on basis Euler equations using a finite difference method in Cartesian grid. The concept of adaptive wall requires that the inner flow match the outer flow at solid wall surfaces. This requirement is satisfied by matching of pressure at both sides of the solid wall-surface.
Numerical wind-tunnel tests of CAST10 and NACA0012 airfoils are performed to de monstrate potentialities of the streamlined 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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Spatial development of disturbance produced from a harmonic point source in compressible boundary layer around a flat plate is simulated for a Mach number of 1.5 by solving the three-dimensional Navier-Stokes equations. A fourth order non-oscillatory scheme and Roe's approximate Riemann solver are utilized for space discretization, and the third-order Runge-Kutta scheme for time integration. The disturbance produced from a source in the upstream spreads in both stream wise and spanwise directions. The wall temperature was varied to examine the effects of wall cooling on the development of disturbance. It turned out that propagation of disturbance takesa wedgelike shape behind the flow source from the wall. The wedge angle and the magnitude of stream wise velocity fluctuation are increased by cooling wall. Furthermore, the lateral spreading angle is close to that of experimental data.

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Transient low pressure on a flat plate was measured when a vortex ring at Re= 7400 impinged on the plate. The pressure was measured with high sensitivity using optical interference as described in the previous paper. The pressure and the resulting force acting on the plate were discussed by connecting with the corresponding flow field.
The major finding in this study is the specific feature that the force acting on the plate has temporally three successive peaks. The occurrence of these peaks correlated basically with the characteristic motions of the main vortex ring, such as the first stage of approaching and the subsequent approaching close to the plate, rebound and the subsequent reapproaching, and then the second stage of rebound and the subsequent final decay of the vortex. The impulse acting on the plate was confirmed to be approximately equal to the momentum of the vortex ring possessing when it travelled without being affected by the plate.

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