旋转效应对低雷诺数共转盘腔流动换热特性影响

Effect of Rotation on Flow and Heat Transfer Characteristics in Co-rotating Cavity at Low Reynolds Number

为探究高空低雷诺数下旋转效应对涡轮共转盘腔内的流动换热特性影响,数值仿真分析了冲击雷诺数为1×10^(3)和2×10^(3)、旋转雷诺数为0~8.8×10^(5)时共转盘腔内流场结构和换热系数分布情况。结果表明:低旋转雷诺数时射流能有效冲击到靶面,高旋转雷诺数时不能有效冲击到靶面;靶面恢复温度沿着径向分布较为均匀,冲击雷诺数分别为1×10^(3)和2×10^(3)时,旋转雷诺数从0增加到8.8×10^(5),靶面平均恢复温度分别升高45和40 K,靶面平均传热系数分别提高44%和50%;随着径向位置增大,靶面传热系数先增大后减小;旋转雷诺数增大,靶面传热系数增大,靶面R/R_(a)=0.81处传热系数最大。

To investigate the effect of rotation on the flow and heat transfer characteristics in a turbine co rotating cavity at high altitude and low Reynolds numbers,numerical simulation analysis was conducted with an impact Reynolds number of 1×10^(3)and 2×10^(3)and rotational Reynolds numbers ranging from O to 8.8×10^(3)for the flow field structure and heat transfer coefficient distribution inside the rotating cavity.The results indicate that the jet can effectively impact the target surface at low rotational Reynolds numbers,but cannot effectively impact the target surface at high rotational Reynolds numbers.The recovery temperature of the target surface is evenly distributed along the radial direction,and when the impact Reynolds numbers are 1×10^(3)and 2×10^(3),the rotational Reynolds number is increased from 0 to 8.8×10^(5),the average recovery temperatures of the target surface are increased by 45 K and 40 K respectively,and the average heat transfer coefficients of the target surface are increased by 44%and 50%,respectively.As the radial position increases,the heat transfer coefficient of the target surface first increases and then decreases;as the rotational Reynolds number increases,the heat transfer coefficient on the target surface increases,with the maximum heat transfer coefficient at R/R_(a)=0.81 on the target surface.