Experimental, theoretical and CFD analysis of hypergravity centrifuge aerodynamics

The aerodynamic environment inside large high-speed hypergravity centrifuges can affect drive power requirements, windage heat generation, pressure loading, and the operation of internal components. This study investigates the aerodynamic behaviour of a reduced-pressure hypergravity centrifuge using a one-third-scale Centrifugal Hypergravity and Interdisciplinary Experimental Facility test rig, torque-balance estimation, and compressible computational fluid dynamics (CFD) simulations. The results show that the internal airflow forms a relatively stable rotating core within approximately 0.8r_b, followed by an outer shear-diffusion region. The air-to-arm velocity ratio remains within a narrow range under the tested conditions, with the CFD prediction consistent with the experimental value. Windage power increases strongly with arm speed and follows an approximately cubic dependence on angular velocity, while pressure reduction decreases air density and substantially reduces windage power and aerodynamic loading. Frequency-domain analysis under the 1000 g/101 kPa condition indicates that the measured pressure-difference signals contain repeatable rotation-related harmonic components. These results provide reference information for aerodynamic assessment and subsequent structural modal or vibration evaluation of high-speed enclosed centrifuges, while the limitations associated with scale, geometry, and measurement conditions are recognised.