基于滑移网格的临近空间螺旋桨流场数值仿真

Numerical Investigation on the Flow Field of Near Space Screw Propeller Based on Sliding Mesh Technique

基于滑移网格模型,考虑RNGk-ε湍流模型,通过求解三维非定常N-S方程,仿真研究了螺旋桨非定常旋转流场,比较研究了20km临近空间环境下不同前进速度、不同转速下螺旋桨气动性能的异同。结果显示,拉力随转速的增大而增大,效率随转速的增大先增大后减小;桨叶周围的速度及速度场的分布范围,涡流强度的大小及涡流强度的分布范围都随转速的增大而增大;桨叶旋转运动产生的诱导速度对螺旋桨前面流场的影响范围较小,对螺旋桨后面流场的影响范围较大。

The unsteady and vertical flow of near space screw propeller was numerical investigation based on the unsteady compressible Navier-Stokes equations with the sliding mesh technique,and the RNG k-ε turbulence model has been considered.The same and different aerodynamic characteristics of propeller work in 20 km near space condition with different forward velocity and rotational velocity has been numerical studied.The results show that,the total thrust of the propeller will keeps increase as the rotational velocity keeps increase with the same forward velocity,and the efficiency of the propeller will increase at first and it will change to decrease when the rotational velocity keep on increase.The velocity and velocity field will keep increase as the rotational velocity keeps increase as will as the vorticity magnitude.The effect of vortical flow cause by rotate to the flow field forward the propeller is big than behind the propeller.