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建立圆柱形腔体热损失性能测试实验台,固定腔体倾角为45°,采用电加热方式对腔体底面和侧面同时加热,探讨有环境风条件时,不同开口率圆柱形腔体在不同风速、风向角下的复合热损失特性,获得混合对流热损失努塞尔特数Nuc和辐射热损失努塞尔特数Nur的拟合关联式,并分析实验过程中的不确定度。结果表明,在有风条件下,对部分开口的圆柱形腔体,对流热损失和辐射热损失随开口率OR的增大而增加,导热热损失随开口率OR的增大而减少;各项热损失随风向角的变化较受开口率的影响要小;开口率增大时,Nuc和Nur均增加;风速增大时,Nuc增加,而Nur减小。
A test bench for the heat loss performance of cylindrical cavity was set up. The inclination angle of the fixed cavity was 45 °, and the bottom and side of the cavity were heated by electric heating simultaneously. When the ambient wind conditions were discussed, , And the composite heat loss characteristics under the wind direction angle, the fitting relation between the Nusselt number Nuc and the Nusselt number Nur of the mixed convection heat loss is obtained, and the uncertainty in the experiment is analyzed. The results show that under windy conditions, the convection heat loss and radiative heat loss increase with the increase of the aperture ratio (OR) for the partially open cylindrical cavity. The heat conduction loss decreases with the increase of the aperture ratio (OR) The change of heat loss with wind direction angle is less affected by the aperture ratio. When the aperture ratio increases, Nuc and Nur increase. When the wind speed increases, Nuc increases and Nur decreases.