基于LES的螺旋桨精细流场特性分析与研究

Analysis and research of propeller fine flow field characteristics based on LES

为了研究大侧斜螺旋桨的精细流场,采用有限体积法结合大涡模拟(LES)模型,对E1619螺旋桨的速度场、压力场、涡量场和湍动能场进行不同程度的分析。模拟结果表明:大涡模拟很好地捕捉了尾流涡结构,梢涡互感合并的本质是相邻的下游梢涡将上游梢涡推向尾流轴向速度较高的内半径区域,梢涡与相邻上游梢涡的随边涡符号相同,导致他们相互吸引;近场轮毂涡比梢涡强度更高是因为轮毂涡包含了叶根涡,且其衰减速度更快;外半径湍动能极大值在梢涡处,且梢涡的不稳定现象极大地影响了外半径湍动能的变化,内半径湍动能先减小后增大,其增大原因是梢涡失稳导致轮毂涡振荡产生湍流。

In order to investigate the fine flow field of a large side-sloping propeller,the velocity field,pressure field,vortex volume field and turbulent kinetic energy field of the E1619 propeller were analysed to varying degrees using the finite volume method combined with the large eddy simulation(LES)model.The simulation results show that the large eddy simulation captures the wake vortex structure well,and that the nature of tip vortex mutual inductance merging is that the adjacent downstream tip vortex pushes the upstream tip vortex into the inner radius region where the axial velocity of the wake is higher,and that the tip vortex and the adjacent upstream tip vortex have the same sign of the following edge vortex,causing them to attract each other.The maximum value is at the tip vortex,and the instability of the tip vortex greatly affects the change of the outer radius turbulent kinetic energy,and the inner radius turbulent kinetic energy first decreases and then increases,which is due to the instability of the tip vortex causing turbulence from the hub vortex oscillation.