基于状态空间法的低马赫数翼型气动载荷计算

Leishman-Beddoes(L-B)非定常动态失速模型适用于中等马赫数(Ma>0.3),而在低马赫条件(Ma<0.3)下存在与翼型气动试验数据不符合的问题,为此首先研究了低马赫数条件下翼型的非定常动态失速气动特性,其次采用状态空间法从翼型表面气流变化的角度修正了L-B模型,最后通过与翼型气动载荷试验数据的对比表明在低马赫数条件下对L-B模型的修正是正确的,能够准确预测及分析翼型的气动载荷,且该修正模型易于耦合进直升机综合分析代码中. 

Prediction of airfoil airload at low Mach numbers based on state space formulation

The Leishman-Beddoes (L-B) unsteady and dynamic stall model is applicable to the medium Mach numbers(Ma>0.3),and some inconsistent problems for predicting airfoil airload when comparing with airfoil airload test data at low Mach numbers (Ma<0.3),so firstly the unsteady and dynamic stall aerodynamic behavior of airfoil at low Mach numbers was investigated,secondly the modified L-B model was set from the viewpoint of the variation of the flow on the airfoil surface,finally the comparisons between the modified L-B and airfoil airload test data at low Mach numbers show that the modified L-B model with state space formulation is accurate and can be used to predict the airfoil airload at low Mach numbers,and also it can be easily incorporated into a helicopter comprehensive code.