Optimisation of Ducted Propellers for Hybrid Air Vehicles Using High-Fidelity CFD
Optimisation of Ducted Propellers for Hybrid Air Vehicles Using High-Fidelity CFD
复制标题
使用高保真 CFD 优化混合动力飞行器涵道螺旋桨
DOI：
10.1017/aer.2016.78
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
G. Barakos
中科院分区：
文献类型：
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作者：
M. Biava;G. Barakos
摘要本文对轻型飞行器用导管式螺旋桨进行了性能分析与设计。首先对推进器的详细模型进行了高保真计算流体动力学模拟，结果与现有实验数据吻合良好。此外，还使用简化的几何图形进行了模拟，以量化风道和叶片扭转对螺旋桨性能的影响。结果表明，风道在低飞行速度下特别有效，并且具有相对高捻度的叶片在飞行包线上具有更好的性能。通过将流动求解器与拟牛顿优化方法相结合，尝试设计最优的捻度分布和管道形状。采用不动点迭代法或带放气重启的嵌套Krylov法求解reynolds -average Navier-Stokes方程的离散伴随方程，计算了流动梯度。结果表明，采用导管式螺旋桨后，其推进效率可提高2%。
ABSTRACT This paper presents performance analysis and design of ducted propellers for lighter-than-air vehicles. High-fidelity computational fluid dynamics simulations were first performed on a detailed model of the propulsor, and the results were in very good agreement with available experimental data. Additional simulations were performed using a simplified geometry, to quantify the effect of the duct and of the blade twist on the propeller performance. It was shown that the duct is particularly effective at low flight speed and that the blades with relatively high twist have better performance over the flight envelope. Design of the optimal twist distribution and of the duct shape was also attempted by coupling the flow solver with a quasi-Newton optimisation method. Flow gradients were computed by solving the discrete adjoint of the Reynolds-averaged Navier-Stokes equations using a fixed-point iteration scheme or a nested Krylov method with deflated restarting. The results show that the ducted propeller propulsive efficiency can be increased by 2%.