摆线桨非定常动态失速的三维效应

对摆线桨三维全尺寸模型进行了非定常数值模拟。验证了两种嵌套网格方法的可靠性与适用性,针对二维/三维情况下摆线桨非定常涡流动特性及诱导分离特性开展了数值分析,重点研究了展向气动力随方位角的分布与全局流场的诱导速度分布,并分析了尾迹捕捉精度与涡量耗散特征。结果表明:受摆线桨切向速度、展向诱导速度等三维效应影响,两种计算结果的瞬态气动力极值差值达到44%。三维动态失速涡的产生、脱落与再附明显弱于二维翼型情况,这对于摆线桨非定常气动特性有较大影响。 

Three-dimensional effect of unsteady dynamic stall of cycloidal propeller

The reliability and applicability of two overset mesh methods were verified. Then numerical analysis of the unsteady vortex flow and induced separation characteristics of cycloidal propeller in the two-/three-dimensional cases was carried out, laying the foundation for studying the distribution of spanwise aerodynamics with azimuth and the induced velocity distribution of the global flow field, meanwhile the wake capture accuracy and vorticity dissipation characteristics were also analyzed. Results showed that, under the influence of three-dimensional effects such as tangential velocity and spanwise induced velocity of cycloidal propeller, the difference of transient aerodynamic extremum between the two calculation results reached 44%. The generation, shedding and reattachment of three-dimensional dynamic stall vortices were obviously weaker than two-dimensional airfoil, yielding a great impact on the unsteady aerodynamic characteristics of cycloidal propeller.