论文标题
串联翼上的流翼的流动的数值模拟：翼展效应
Numerical simulation of flow over flapping wings in tandem: wingspan effects
论文作者
论文摘要
我们报告了水平串联配置中一对机翼的直接数值模拟，以分析其长宽比对系统的流量和系统的空气动力性能的影响。翅膀浸入雷诺数的均匀自由流中RE = 1000，它们会以Strouhal数字st = 0.7进行重大和俯仰振荡。前挥发性和后翼的纵横比在2到4之间各不相同。系统的空气动力学性能取决于前面的后缘涡流（TEV）之间的相互作用，而前孔与在后翼上形成的诱导的前沿涡流之间的相互作用。前提的空气动力学性能与孤立的机翼的空气动力性能相似，而不论侧翼的纵横比，较小的调节效应是由前翼相互作用产生的较小的调节作用。另一方面，助后的空气动力学性能显然受到与前提tev的互动的影响。前面的纵横比较大的串联配置比在后翼上具有更大的纵横比导致后者的准两维流结构。这使后翼的时间平均推力系数增加了8％，其推进效率没有变化。
We report direct numerical simulations of a pair of wings in horizontal tandem configuration, to analyze the effect of their aspect ratio on the flow and the aerodynamic performance of the system. The wings are immersed in a uniform free-stream at Reynolds number Re = 1000, and they undergo heaving and pitching oscillation with Strouhal number St = 0.7. The aspect ratios of forewing and hindwing vary between 2 and 4. The aerodynamic performance of the system is dictated by the interaction between the trailing edge vortex (TEV) shed by the forewing and the induced leading edge vortex formed on the hindwing. The aerodynamic performance of the forewing is similar to that of an isolated wing irrespective of the aspect ratio of the hindwing, with a small modulating effect produced by the forewing-hindwing interactions. On the other hand, the aerodynamic performance of the hindwing is clearly affected by the interaction with the forewing's TEV. Tandem configurations with a larger aspect ratio on the forewing than on the hindwing result in a quasi-two-dimensional flow structure on the latter. This yields an 8% increase in the time-averaged thrust coefficient of the hindwing, with no change in its propulsive efficiency.
