一种新型半转扇翼气动特性的数值分析

Numerical Analysis of Aerodynamic Characteristics of a New Type of Half-Rotating Fanwing

半转扇翼是基于半转机构的一种新型活动性叶轮扇翼,其叶轮运动原理不同于普通扇翼的固定叶轮,为使其在工作时获得较优的气动力,需要对不同结构参数与运动参数下的半转扇翼进行具体探究。本文通过数值计算方法对半转扇翼叶轮偏角、底槽相位与叶片数目的影响做了详细的计算与剖析,并对比分析了不同来流速度与转速对半转扇翼气动特性的影响。计算结果表明:叶轮偏角是影响扇翼升推力的主要因素,其在20°~40°时取得较佳气动力效果;不同底槽前后缘开口角(φ,β)下扇翼的气动特性也有所差异,使用C(φ<β)型与U(φ=β)型底槽的机翼具有较好的综合气动特性优势;叶片数目亦对扇翼的气动力有所影响,叶片数目在10~14时足以达到半转扇翼的气动力需求。与固定叶轮扇翼相比,半转扇翼在同样转速与来流速度下能产生与之相近的气动力,从而明确了半转扇翼拥有良好的基本气动特性。

Half-Rotating Fanwing(HRF)based on Half-Rotating Mechanism(HRM)is a new type of active impeller fanwing.Its impeller motion principle is different from the fixed impeller of ordinary fanwing.In order to obtain better aerodynamic force in working,it is necessary to explore the HRF in different structural parameters and motion parameters.The numerical calculation method is used to calculate and analyze the influence of the impeller deflection angle,the bottom slot phase and the number of blades of HRF in detail,and the influence of different inflow speeds and rotational speeds on the aerodynamic characteristics of the HRF is compared and analyzed.The calculation results show that the impeller declination angle is the main factor affecting the lift and thrust of the fanwing.When the impeller declination angle is between 20°and 40°,the best aerodynamic effect can be obtained.The aerodynamic characteristics of the fanwing under the opening angles of the front and rear edges(φ,β)of the different bottom grooves are also different.The fanwing using the C(φ<β)and U(φ=β)bottom grooves have better comprehensive aerodynamic characteristics.The number of blades also affects the aerodynamic force of the fanwing.When the number of blades is between 10 and 14,it is enough to meet the aerodynamic requirements of the HRF.Compared with the fixed impeller fanwing,HRF can generate similar aerodynamic force at the same rotational speed and incoming flow speed,which confirms that the HRF has good basic aerodynamic characteristics.