摘 要：建立了一个基于计算流体力学（CFD）技术的直升机旋翼/尾桨/垂尾气动干扰分析方法。在该方法中，选取Navier-Stokes方程为控制方程对旋翼和尾桨贴体网格进行求解，并采用Baldwin-Lomax（B-L）模型为湍流模型；为了实现旋翼、尾桨和垂尾网格之间的流场信息交换，采用了运动嵌套网格方法；使用二阶迎风的Roe格式进行空间离散，并选取隐式LU-SGS格式进行时间推进。应用所建立的方法，对C-Tung旋翼和Lynx直升机尾桨进行了流场算例计算，并与可得到的试验数据进行对比，验证了方法的正确性。然后，着重针对旋翼/尾桨干扰特性进行了计算，并进一步计入垂尾的干扰，对垂尾/尾桨干扰以及旋翼/尾桨/垂尾干扰特性分别进行了研究，分析了旋翼/尾桨、垂尾/尾桨和旋翼/尾桨/垂尾的气动干扰规律。结果表明：对于不同的垂尾/尾桨构型，阻塞面积越大，对应的尾桨拉力也较大，但尾桨和垂尾获得的净拉力却减小，且不同阻塞面积下，推力式构型尾桨比拉力式尾桨具有更大的净拉力。
Abstract: A computational method based on CFD technology is developed for helicopter main-rotor/tail-rotor/ vertical-tail interaction analysis. In the present method, Navier-Stokes equations are utilized as the control equations, and the Baldwin-Lomax model is used as the turbulence model. Moving embedded grid method is applied to exchange the flowfield information among the grids of main-rotor, tail-rotor and vertical-tail. For the spatial and time discretization, the second-order upwind Roe scheme and implicit LU-SGS scheme are used respectively. By the method developed, example calculations on the flowfield of well-known C-Tung rotors and Lynx tail rotors are performed, and the validity of the present method is demonstrated by comparing the calculated results with available experimental data. Then, numerical simulations for main-rotor/tail-rotor aerodynamic interference are made, furthermore, taking vertical tail interaction into consideration, tail-rotor/vertical-tail and main-rotor/tail-rotor/vertical-tail interaction calculations are conducted to investigate the interaction mechanism among main rotor, tail rotor and vertical tail. It is shown that, for different vertical-tail/tail-rotor configurations, a larger blockage area always leads to a greater tail-rotor trust, but a smaller clean trust of vertical tail and tail rotor. In addition, the clean tail-rotor trusts of “push configuration” are always higher than that of the “pull configuration” for different blockage areas.
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