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建立了一个耦合高效配平策略和计算流体力学(CFD)技术的旋翼气动特性分析方法.采用CFD求解器进行雅克比矩阵和旋翼流场的计算,建立了一个包含直接配平法的旋翼气动特性分析平台;引入差量法思想对配平策略进行简化,发展了一种差量配平法,解决了直接配平法中雅克比矩阵计算效率低下的问题,显著缩短了计算时间.旋翼流场求解中控制方程采用Navier-Stokes方程,空间离散格式选取2阶迎风Roe格式,时间推进采用隐式lower-upper symmetric Gauss-Seidel(LU-SGS)格式,湍流模型为Baldwin-Lomax(B-L)模型.分别采用建立的基于直接配平方法和差量配平方法的气动特性分析平台对AH-1G和Helishape 7A直升机的旋翼进行了配平计算和研究,对比分析了两种配平方法的计算效率和精度及背景网格的网格量对配平结果的影响.结果表明:与直接配平法相比,耦合差量配平法的气动特性分析方法计算圈数更少,可节省至少60%的计算时间;使用疏化的背景网格虽然不利于捕捉流场细节,但是可以在兼顾配平结果准确性的同时,降低配平计算代价,提高旋翼配平和流场计算的效率.
A method of rotor aerodynamics coupled with high efficiency trim strategy and computational fluid dynamics (CFD) technique was established.The CFD solver was used to calculate the Jacobian matrix and rotor flow field, and a rotor aerodynamic performance analysis platform ; Introduced the idea of the difference method to simplify the trim strategy and developed a differential trim method to solve the problem of low computational efficiency of the Jacobian matrix in the direct trim method and significantly shorten the computation time.The control equations in the rotor flow field are solved by Navier-Stokes equation, the second-order upwind Roe scheme is selected as the spatial discretization scheme, the time advance is in the form of an implicit lower-upper symmetric Gauss-Seidel (LU-SGS), and the turbulent model is the Baldwin-Lomax (BL) The aerodynamic characteristics analysis platform of direct grading method and differential grading method was used to calculate and study the rotors of AH-1G and Helishape 7A helicopters. The computational efficiency and accuracy of the two grading methods and the grid amount of background grid The results show that compared with the direct doping method, the calculation method of the aerodynamic characteristics of the coupled doping doping method The number of fewer, can save at least 60% of the calculation time; use of the background of the thinning of the grid is not conducive to capture the details of the flow field, but can take into account the accuracy of the results of trim, while reducing the cost of trim calculation and improve rotor trim and flow field Calculated efficiency.