傾斜内壁をもつシャープターン往復流路内の伝熱特性 : 熱工学,内燃機関,動力など

Experimental study was conducted on heat transfer characteristics in rectangular cross-sectioned two-pass serpentine channels with an inclined partition wall. The cross section of the channel at the entrance was 50 mm×25 mm, and the inclination angle of the partition (inner) wall was changed from -6° (convergent channel) to +6° (divergent channel) for three turn clearances of 30 mm, 50 mm, and 70 mm. Distributions of local heat (mass) transfer rates on the long-side wall were measured by the naphthalene sublimation method under a single Reynolds number of 3.5×104. In this paper, influences of the inclination angle of the partition wall and of the turn clearance on heat transfer characteristics in the channels are discussed in detail. Then, the optimum combination of the inclination angle and the turn clearance is examined from viewpoints of the trade-off between the mean heat transfer rate and pressure loss, and of the improvement of uniformity in the distribution of local heat transfer rates.