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Vibration and thermal analysis of hermetically sealed reaction wheel for attitude control of satellite

Reaction Wheels (RWs) provide precise pointing accuracies in attitude control of satellites. They are frequently used in satellite due to their high reliability, less power consumption and wide range of torque capability. This paper presents the detail design analysis of nitrogen purged hermetically sealed reaction wheel. The RWs are major source of vibrations in the satellite. Therefore, the methodology for the attenuation of static and dynamic imbalances of the current reaction wheel is adapted as per ISO standard 1940/1 and is discussed in detail. Transient and steady state thermal analyses of the reaction wheel are carried out to ensure the proper heat transfer from the RW to the satellite body and are presented in detail in this paper. The reaction wheel assembly (RWA) is hermetically sealed by nitrogen gas and extensive testing on ground has been performed for the determination of gas leakage. A smooth decay curve is obtained which shows good agreement with the theoretically simulated results. A parametric approach has been adapted for design optimization on the basis of experimental and simulated data.