수평형 타공판의 소파특성

Abstract

In this paper, wave absorbing characteristics of a horizontal submerged punching plate areinvestigated throughout the calculation and the experiment. The punching plate with the aray of circular holescan force the flow to separate and to form edies of high vorticity and cause significant energy loss. As ananalytic tol, the linear water wave theory and the eigenfunction expansion method is applied. Darcy's law thatthe normal velocity of the fluid passing through the punching plate is linearly proportional to the pressurediference between two sides of the punching plate is asumed. The proportional constant called the porouscoefficient is deply dependent to the porosity. To obtain the relationship betwen the porosity and the porouscoefficient, the systematic model test for the punching plates with 6 different porosities is conducted at 2-dimensional wave tank. It is found that the porous coeficient is linearly proportional to the porosity(b=57.63P-0.9717 .. It is also noted that the optimal porosity value is near P=0.1 and the optimal range of submergence depthis d/h 0.2 within entire frequency range.