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通过三维数值模拟的方法研究了射流孔交错偏置排布下的楔形凹表面对流换热,在射流孔偏置间距比(L/d)为0~2.5、射流孔距凹腔前缘间距比(H/d)为6~12、射流冲击雷诺数(Re)为10 000~28 000的研究参数下,研究结果表明射流孔交错偏置排布在凹腔中诱导复杂的涡流,对应于射流冲击驻点区的局部表面传热系数得到增强;相对于直线排布的射流孔,小射流孔交错偏距比能够使得凹腔前缘附近沿弦向的展向平均努塞尔数相对射流孔直线排布方式有所改善,随着射流孔交错偏距比增加,沿弦向的展向平均努塞尔数最大值所对应的弦向位置逐渐向凹腔前缘下游迁移.为了在保持凹腔前缘对流换热能力不受到显著削弱的前提下,改善凹腔前缘附近的射流冲击对流换热能力,射流孔交错偏距比宜选择在1倍射流孔直径左右.
The three-dimensional numerical simulation method was used to study the convective heat transfer on the wedge-shaped concave surface under the staggered arrangement of jet holes. The offset ratio (L / d) of the jet holes was 0-2.5. The ratio of the jet holes to the leading edge of the cavity The results show that the staggered bias of the jet holes in the cavity induces complex eddy currents, corresponding to the impact of jet impingement The local surface heat transfer coefficient in the stagnation zone is enhanced. Relative to the jet holes arranged in a straight line, the stagger ratio of the small jet holes can make the chord direction of the cavity near the leading edge average Nusselt number relative to the jet hole straight line As the cross-offset ratio of jet holes increases, the chordwise position corresponding to the maximum Nusselt number along the strike direction of the jet gradually migrates toward the downstream of the front of the cavity. On the premise of not significantly weakened the convective heat transfer ability of the leading edge, it is better to choose a jet diameter of about 1 times to improve the convective heat transfer capacity of the impingement jet near the front edge of the cavity.