| Budget Amount *help |
¥3,400,000 (Direct Cost: ¥3,400,000)
Fiscal Year 2003: ¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 2002: ¥1,300,000 (Direct Cost: ¥1,300,000)
|
|---|
| Research Abstract |
The lift of aerofoil in the ground effect increases, because the ram pressure between the aerofoil and the ground is strengthen. The width of the wing is limited, the ram pressure decreases gradually to zero at the end of the wing. To keep the ram pressure at high level, we proposed the new system which has surface pattern on the ground, which prevents the air to flow the sideways. It has several longitudinal fences on the ground surface.
The aerofoil flying in the close proximity to the ground is strongly affected by the ground through fluid viscosity. The conventional wind tunnel can not estimate the aerodynamic characteristics of the aerofoil near the wind tunnel wall, because the aerofoil does not run relative to the wall. So, it is necessary to run the aerofoil relative to the ground. We. designed a system in which the wing rotates about the axis of the circular disk whose height is precisely controlled by the stepping motor. The wing section is NACA4412, chord length 100mm, width 200mm, the outer diameter of the rotating wing is 1000mm. Inner diameter of the circular disk is 600mm and outer diameter is 1000mm.
The longitudinal hence on the ground has 2mm height of papers. The distance between neighboring hence is 1cm. When the height of the wing trailing edge is less the 20% of the chord length, the lift force increase and the tendency is strong, the attack angle decrease to the lower surface of the wing is parallel to the ground.
|
