In the present study, the interaction effect by inter-rotor spacing of coaxial rotor blades in hovering and forward flight is studied by using a Reynolds-averaged Navier–Stokes CFD flow solver based on mixed meshes. The meshes were composed of unstructured near-body region and Cartesian off-body region. The flux-difference splitting scheme of Roe was used for computing inviscid fluxes on the near-body region, whereas the 7th order WENO scheme was used for the computation of the inviscid fluxes on the off-body region to capture vortex with high resolution. The predicted results of the baseline inter-rotor spacing were compared with the reference results of other researchers for validation. The computed results of three different inter-rotor spacings were compared in terms of the thrust and torque coefficients for each flight condition. The cause of the different interaction effect by inter-rotor spacing between hovering and forward flight was also investigated.

中文翻译：

---

同轴转子叶片气动相互作用的数值研究

在本研究中，使用基于混合网格的雷诺平均 Navier-Stokes CFD 流动求解器研究了悬停和前飞中同轴转子叶片的转子间距的相互作用效应。网格由非结构化的近体区域和笛卡尔离体区域组成。Roe 的通量差分裂方案用于计算近体区域的无粘通量，而 7 阶 WENO 方案用于计算离体区域的无粘通量以高分辨率捕获涡流。将基线转子间距的预测结果与其他研究人员的参考结果进行比较以进行验证。三种不同转子间距的计算结果在每种飞行条件下的推力和扭矩系数方面进行了比较。