前飞状态直升机旋翼/机身非定常气动干扰的分析

一个计算旋翼/机身/尾迹间非定常气动干扰的分析方法是建立在二阶升力线/全展自由涡模型和机身面元模型基础之上的。通过迭代机身在桨盘平面、尾迹定位点的诱导速度和旋翼/尾迹在机身表面的诱导速度，形成一个耦合的分析模型。在分析中计入了非定常项。作为算例，对两种孤立机身表面的平均压强系数分布以及旋翼机身组合体中机身表面的非定常压强系数分布进行了计算，其结果与实验值相吻合。

Analysis of unsteady aerodynamic interactions between rotor and fuselage of helicopters in forward flight

An analytical method, which calculates the unsteady a erodynamic in teractions between the rotor and its wake and the fuselage of helicopters, is ba sed on the blade secondorder liftingline model, the rotor fullspan free wa ke model, and the fuselage source panel model. These models are coupled together to form a global analytical model by iterating on the induced velocities of the fuselage on the rotor inflow plane and collocating points of the wake as well a s the rotor and its wake on the surface of the fuselage. The unsteady term was incorporated into this analysis. As numerical examples, calculations are carrie d out on the meantime pressure distribution for two isolated fuselages and the unsteady pressure coefficient for a combined rotor/fuselage configuration. Thr ough the comparison between the calculated results and available experimental da ta, the capability of the present method is indicated.