スラットを用いた後向きステップ下流の再付着領域の熱伝達促進

抄録

The effects on the local heat transfer and pressure coefficients of a slat downstream of a backward-facing step were investigated. The inclinations of the slat placed on the wall opposite the step were varied in the range of θ = 10∼60° for both slat lengths of 20 mm and 30 mm, with the aim of augmenting and controlling the heat transfer characteristics. The reattachment region of the main flow shifted upstream due to the increase of the amount of circulating bubbles formed behind the slat when the inclination angle was increased, which enhanced the heat transfer in the recirculating region. These tendencies are marked with a large expansion ratio. It was also found that the performance ratio η (the ratio of averaged heat transfer with a slat to that without a slat under the condition of equivalent pumping power) is larger than unity.