翼型超低雷诺数气动特性研究

采用多块格子玻尔兹曼方法(Lattice Boltzmann Method,LBM)研究超低雷诺数下翼型的气动特性。在超低雷诺数下,由于粘性作用十分显著,流动呈现明显的非定常特性,引起前后缘层流分离与再附以及涡脱落现象。结果表明粘性作用改变了翼型的有效攻角与有效弯度,对翼型的气动性能有重要影响。翼型厚度增加明显降低了升阻比,翼型几何弯度的增加可以补偿粘性作用引起的有效弯度的减小,雷诺数的减小会减小翼型的升阻比。

Exploring with Multi-Block LBM Aerodynamic Characteristics of Airfoil at Ultra-Low Reynolds Number

Aim.The introduction of the full paper reviews some papers in the open literature and then proposes our method of exploration——the multi-block lattice Boltzmann method(LBM),which is explained in section 1;eq.(12) is particularly worth paying attention to.The simulation results at ultra-low Reynolds number of several thousands,presented in Figs.4 through 14 and Table 1,and their analysis show preliminarily that:(1) the viscous effect changes the effective angle of attack and camber of the airfoil,greatly influencing its lift and drag;(2) the increase in the thickness of an airfoil decreases its lift-to-drag ratio;(3) the increase in geometrical camber can compensate for the loss of effective camber and the decrease in the Reynolds number leads to the decrease in the lift-to-drag ratio.