Control of Impinging Jet Heat Transfer with Mesh Screens

Mesh 스크린을 이용한 충돌제트 열전달 제어에 관한 연구

The local heat transfer rate of an axisymmetric submerged air jet impinging on normal to a heated flat plate was investigated experimentally with varying solidity of mesh screen. The mean velocity and turbulent Intensity profiles of streamwise velocity component were measured using a hot-wire anemometry. The temperature distribution on the heated flat surface was measured with thermocouples. The screen installed in front of the nozzle exit(behind of 35mm) modify the jet flow structure and local heat transfer characteristics. For higher solidity screen, turbulence intensity at core lesion is high and increases the local heat transfer rate at nozzle-to-plate spacings(L/D<6). For larger nozzle-to-plate spacings(L/D>6), however, the turbulent Intensities of all screens tested in this study approach to an asymptotic curve, but the small mean velocity at the core region reduces the local heat transfer rate for high solidity screens.