Analysis of influencing factors on gas film characteristics for hemispherical dynamic pressure motors

Abstract

The hemispherical dynamic pressure motor (HDPM) has the advantages of high speed, wear resistance and stability, which is widely used in inertial instruments to produce the gyroscopic effect. The ultra-thin gas film between the stator and rotor of the motor provides dynamic pressure lubrication and bearing capacity, whose dynamic characteristics determine the motor performance. However, the influence mechanism of some key factors such as ball center distance on the film characteristics is not clear, which has become the bottleneck restricting the performance improvement of HDPMs. Therefore, in this paper, a series of gas film similarity models were solved under different geometric and working parameters, and the influence law of the ball center distance, rotor displacement and stopping process on the aerodynamic characteristics was obtained, the results show that these primary parameters have significant effects on the pressure distribution, resistance moment and frictional heat of the ultra-thin gas film. This work can not only provide a theoretical basis for the aerodynamic performance optimization of HDPMs, but also serve as a reference for the design of other aerodynamic instruments.