Flow and Heat Transfer Characteristics of a Channel with Cut-fins (3rd report: Effect of Notch Arrangement Angle)

摘要

Three-dimensional numerical simulation and heat transfer experiment were conducted for a channel with cut-fins mounted on the bottom wall. The effects of the fin tip clearance and attack-angle of the notch array were evaluated in the present paper. Larger reduction of pressure loss was obtained under smaller clearance conditions, while a smaller thermal resistance was achieved with larger clearance by the cut-fins compared with fins without notches. A maximum peak, therefore, appeared in the overall performance in relation with the clearance size. Larger heat transfer coefficients were obtained with smaller attack-angle of the notch array in both experimental and numerical results, particularly under larger Reynolds number conditions. This was due to the spanwise flow generated in the area adjacent to the notch, by which a larger effect of the redevelopment of the thermal boundary layer was produced at the trailing edge of the notch.