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本文测试了人工构建的一维短沟槽复合准晶结构对流体的减阻性能,并与一维短沟槽复合周期结构和一维沟槽周期结构的流阻进行了对比.实验结果表明,一维短沟槽复合准晶结构的减阻效果优于一维短沟槽复合周期结构,其中一维短沟槽十二重复合准晶结构的减阻效果最佳,同时与一维沟槽周期结构具有同样的减阻效果.在机理分析方面,建立了二维光栅的夫琅禾费衍射波模型,对通过一维短沟槽复合准晶结构的波谱特征进行模拟分析.频谱分析表明,经过二维准周期光栅的相干波强度谱具有谱带结构特征,抑制了大角度方向上的强峰形成.这一结果与流体流过一维短沟槽复合准晶结构相对应,展向上的准周期结构在激活边界层微扰动的同时,也使得二次涡分布比较均匀,从而抑制了展向强扰动的形成,所以能够有效减小流阻.
In this paper, the drag reduction performance of artificial one-dimensional short-groove composite quasicrystal structure was tested and compared with that of one-dimensional short-groove composite periodic structure and one-dimensional trench periodic structure. The experimental results show that, The drag reduction effect of one-dimensional short-groove compound quasicrystal structure is better than that of one-dimensional short-groove compound periodic structure, in which the one-dimensional short-groove twelve-fold compound quasicrystal structure has the best drag reduction effect, The periodic structure has the same drag reduction effect.In the aspect of mechanism analysis, a Fraunhofer diffraction wave model of two-dimensional grating is established to simulate the spectral characteristics of the quasi-crystal structure with one-dimensional short grooves. The spectral analysis shows that, The intensity spectrum of the coherent wave after two-dimensional quasi-periodic gratings has the characteristics of the band structure and suppresses the formation of strong peaks in the large-angle direction. This result corresponds to the fluid flowing through the one-dimensional short-groove compound quasicrystal structure, The quasi-periodic structure also activates the perturbation of the boundary layer, and at the same time makes the distribution of the secondary vortex more uniform, so as to suppress the formation of the spreading disturbance. Therefore, the flow resistance can be effectively reduced.