Study on Turbulent Channel Flow with Injection through an Inclined Slit : Influence of Injection Flow Rate

Experiments have been performed on turbulent channel flow with injection through an inclined slit. The inclined angle is fixed to 30 degrees at the main stream velocity 10 m/s. The dimensionless injection flow ratio is varied eight steps in ranging 0.067-0.467. The cooling effectiveness, wall static pressure, wall shear stress, velocity profile and turbulent intensity are measured behind the slit. In addition, the temperature distribution is measured. The cooling effectiveness and pressure loss increases with increasing the injection flow ratio. When the injection flow ratio is 0.433, the highest cooling effectiveness is obtained. Turbulent intensity and Reynolds shear stress near the slit show the high peak in the near-wall region. However, this peak rapidly decays in the downstream direction. This phenomenon relates to improvement in the cooling effectiveness.