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In order to make more effective use of simulation, a new evaluation method on pressure loss has been developed. Using this method, the location and amount of pressure loss is clarified. As a result, enormous simulation data have been used effectively. The authors have confirmed the validity of the method about fundamental shapes.

Flows around a forward facing step and a fence are simulated on structured grid to estimate aerodynamic noise by using direct simulation. Calculated results of sound pressure level show quantitatively good agreement with experimental results. To estimate aerodynamic noise from 3D complex geometry, a simplified side mirror model is also calculated. Averaged pressure distribution on the mirror surface as well as pressure fluctuations on the mirror surface and ground are simulated properly. However, calculated result of sound pressure level at a location is about 20dB higher than experiment due to insufficient spatial resolution. To capture the propagation of sound waves, more accuracy seems to be required.

When shock impinges on the bow shock ahead of a blunt body, the shock-shock interaction occurs. Such interactions are classified into six patterns by Edney. In the present research we selected an interaction referred to as Type IV, where the impinging shock was generated by another blunt body. It is well known that pressure and heat transfer are greatly increased at the impinging point. We measured the pressure distributions along the body surface where shock impinges. Then, we performed numerical simulations to investigate the heat transfer rate and the interaction pattern, though it is two-dimensional for simplicity. We employed the FVS, Flux Vector Splitting, method to solve the Navier-Stokes equations. From the numerical simulations, the clear interaction pattern was obtained and it was found that this pattern is an unstable phenomenon.

A thick delta wing with a rounded leading egde has been experimentally studied. To understand the basic flow field of such a wing, experiments have been conducted in low speed wind tunnel at Nagoya university. Three types of flow visualization: oil flow, smoke wire, and tuft methods are employed, and forces: lift and drag, and pressure distributions were also obtained. The same test has been conducted for a thin delta wing for comparison. The results show the different flow field of the thick delta wing from those commonly known for delta wings. However, in other properties except for the flow pattern, similarities were observed between the thick delta wing and thin delta wing.