低速风洞均匀吸气地板下阻塞对地板边界层影响的研究

Investigation on bottom blockage affection on boundary layer of a plate with uniform suction in low speed wind tunnel

为了研究低速风洞地板下部阻塞对地板上表面边界层的影响以及控制方法,在国防科技大学KD-03低速风洞利用均匀吸气地板系统进行了实验研究。地板下部阻塞对地板上表面主流区的流动产生干扰,并影响边界层的分布和发展,随着地板下部阻塞度的增加,地板上表面边界层的厚度有增加的趋势;在某一阻塞度和吸气系数下,来流速度越大,地板下部的阻塞对主流区流动的影响越小;地板的均匀吸气使边界层的厚度显著降低,也有效减小因地板下部阻塞引起的主流区流动的不均匀性。该实验的研究结论为8m×6m风洞均匀吸气地板系统研制提供了参考。

To investigate the bottom blockage wind tunnel and the control method, the experiment affection on boundary layer above the plate in low speed research by a plate with uniform suction system is performed in KD-03 low speed wind tunnel of NUDT. The flow of main stream above the plate is interfered by the bottom blockage, the distribution and growing of boundary layer are also interfered, the trend of the boundary layer thickness above plate is increased with the increase of blockage degree below plate. Under one blockage degree and suction coefficient, while the velocity of incoming flow is bigger, the bottom blockage affection on the flow in main stream is smaller; the boundary layer thickness could be remarkably reduced by uniform suction of plate,and the flow nonuniformity of main stream brought by blockage below the plate could be efficiently reduced. The investigation conclusions of this experiment provide a reference for developing a plate with uniform suction system in 8m × 6m wind tunnel.