In this paper, blade planform effects and airfoil shape coefficients on aerodynamic efficiency of helicopters in hover flight are investigated. The procedure emphasizes small composite data (SCD), airfoil representation method, and numerical optimization and is presented as generalized process to the rotor blade design optimization problem. Therefore, the systematic evaluation of blade taper, taper point on the blade, linear twist, tip sweep, and airfoil shape coefficients on figure of merit (FM), rotor thrust, and power required is provided with the proposed procedure. The SCD data were generated through the in-house flight dynamic simulation program in which the model of rotor is a nonlinear dynamic model developed for rotors and the unsteady aerodynamic representation with a three-state dynamic inflow model. The results show that this procedure alleviates the challenges associated with complex and time-consuming approaches required computational fluid dynamics CFD analysis. The results also confirm that the optimum swept-tapered blade with cambered airfoil lowers the power required in hover by about 7% and enhances the FM up to 10% with an acceptable improvement relative to the rectangular planform with NACA 0012 cross section.

本文研究了叶片平面形状效应和翼型形状系数对直升机在悬停飞行中气动效率的影响。该程序着重于小合成数据（SCD），机翼表示方法和数值优化，并作为对转子叶片设计优化问题的通用过程而提出。因此，建议的程序提供了对叶片锥度，叶片锥度点，线性扭曲，叶尖扫掠和品质因数（FM），转子推力和所需功率的机翼形状系数的系统评估。SCD数据是通过内部飞行动力学仿真程序生成的，其中，转子模型是针对转子开发的非线性动力学模型，以及具有三态动态流入模型的非定常空气动力学表示。结果表明，该程序减轻了与复杂且耗时的方法相关的挑战，这些方法需要计算流体力学CFD分析。结果还证实，相对于带有NACA 0012横截面的矩形平面，具有弧形翼型的最佳后掠锥形叶片将悬停所需的功率降低了约7％，并将FM提升了10％，并且具有可接受的改进。