可调桨距冲压空气涡轮气动特性实验与数值分析

The Aerodynamic Characteristic Experiment and Numerical Analysis of Ram Air Turbine with Autocoarse Pitch

冲压空气涡轮风洞实验主要目的是采用相似准则,模拟空中加油工作状态,测量涡轮输出功率,分析涡轮气动特性。实验分别使用励磁发电机和加油泵作为测功器,通过调桨变距并测量最大输出功率。气动特性实验表明在风洞气流速度比加油机最小飞行速度低16%的条件下,冲压涡轮输出功率即可满足加油需要。论文还采用高数值稳定性代数Baldwin-Lomax湍流模型模拟冲压涡轮全三维混合型流场,分析流场主要气动特性,讨论桨叶表面载荷的分布。数值模拟结果显示在冲压空气涡轮桨叶近轮毂区域需要进一步优化。

The aim of wind tunnel experiment of ram air turbine was mainly to simulate the real flightrefuel conditions on the basis of employing similarity criteria.In the meantime,the output power of the turbine was measured,and its aerodynamic characteristics were further analyzed.An exciter motorgenerator and a refueling pump were used as the dynamometer machine.The maximal output power could be obtained by means of adjusting the pitch of ram turbine blades.It was found that the output power of ram air turbine can satisfy the flightrefuel needs on conditions that the air speed of wind tunnel is 16% lower than the minimal flight speed of aircraft tanker.The BaldwinLomax turbulence model with highly numerical stability was used to simulate the 3D internal and external mixed flow fields of ram air turbine.The main dynamic parameters of turbine flow field were investigated and the cause of load distributing on the blades surface was also discussed.It was revealed that the ram air turbine performance could be improved by optimizing the blades near the hub region.