Abstract: In order to investigate the windage loss on the rotating disc in unshrouded rotor-stator systems，a purpose test rig was applied to measure the frictional torque with static torquemeter as air passed through the rotor-stator system. The unshrouded and the shrouded stationary cases were both investigated with various gap ratio and the flow parameter. The experimental data and an associated correlation for the moment coefficient for the unshrouded case were also presented. The results show that the flow regime，being identified by the turbulent flow parameter plays an important role on friction torque. The flow in the cavity whether is rotational dominant or throughflow dominant will affect the moment coefficient of the rotor. Compared with free disc case，the friction torque of the unshrouded case is mainly affected by the gap ratio. Two critical gap ratios are found with the torque data，the minimum one is G=0.02～0.04 and the maximum one is G=0.06～0.08. For the throughflow dominant case，the moment coefficient of the unshrouded case is about 5 to 15 percent less than the free disc case. The presence of the shroud will enhance the moment coefficient by 20%.

Key words: Rotor-stator system；Windage loss；Friction torque；Moment coefficient

摘要： 采用实验的方法对中心进气开式转静系转盘的风阻扭矩特性进行了研究，利用特殊的测量装置设计，实现利用静止扭矩仪测量转盘受到的风阻扭矩。结合流动参数以及转静间隙比等变量，对比研究了有无封严结构的转静系两种模型，并总结出开式转静系转盘的扭矩系数经验关系式。结果表明，转盘的风阻扭矩主要受到腔内的流动结构影响，腔内流体的流动形式，旋转主导或者通流主导对转盘扭矩系数有着不同的影响。对比自由盘，开式转静系中静盘对扭矩系数的影响与间隙比的大小有关。分析实验数据发现最小临界间隙比以及最大临界间隙比的范围，分别为G=0.02～0.04以及G=0.06～0.08，当间隙比较小且腔内旋转主导，转盘扭矩会比对应参数自由盘模型小5%～15%，而出口封严环罩会使得转盘扭矩系数增大20%。

关键词: 转静系；风阻损失；摩擦扭矩；扭矩系数