抄録
The windage loss gives some contribution to the total losses of high-speed rotary machine such as motor/generator with flywheel or turbines. In order to overcome this problem, the rotor can be operated in a low pressure/vacuum chamber. However, this method finds difficulties in removing heat from the rotor, to seal and to design suspension system. In addition, its breakdown voltage is very low. This paper presents experimental results of windage loss reduction using helium and air mixture that also has the property of cooling gases. The results show significant windage loss reduction for Helium (50%) and air (50%) mixture with a breakdown voltage of about 88% that of the air. The breakdown voltage and thermal property of the gases have also been measured.
