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An Investigation to Find the Effects on Air Foil Bearing by the Variation of Foil’s Structural Parameters


Affiliations
1 Department of Mechanical Engineering, National Institute of Technology Agartala, Tripura 799 046, India
2 Department of Production Engineering, National Institute of Technology Agartala, Tripura 799 046, India
 

The newest advancement in the realm of bearing technology, Air Foil Bearings (AFB) is a marvel that allows for operation at both incredibly low and high temperatures without fail. Their minimalistic design eliminates the requirement for lubrication and sealing systems, making them not only more efficient but also more eco-frienadly. When it comes to speed, these bearings give no quarter - they can handle even the most extreme of conditions with ease. Air foil bearings rely on the structural design of top and bump foils to support and distribute pressure in the air film. To increase bearing capacity, these foils must be thick enough to withstand greater force. It is crucial to explore how varying foil thickness and bump height-pitch ratios may affect the performance of an air foil bearing. The researchers at the ANSYS Fluent lab set out to understand the dynamics of air foil bearings. By adjusting the thickness of the top and bump foils, they were able to observe how stress, stiffness, and air film clearance changed in relation to each other. Their results showed that even minor changes in foil thickness, bump height, and bump pitch had a significant impact on bearing performance. With their discoveries, these engineers have unlocked a new understanding of this complex technology - one that will help guide its continued development into the future. The thickness of the foil may not confer much strength, but it certainly does wonders for reducing stress and maintaining load-bearing capabilities. Its suppleness, however, cannot be denied – a boon for air foil bearings.

Keywords

Bump Foil, Foil Thickness, Minimum Air Film Thickness, Top Foil, Unit Stiffness.
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  • An Investigation to Find the Effects on Air Foil Bearing by the Variation of Foil’s Structural Parameters

Abstract Views: 121  |  PDF Views: 91

Authors

Bivash Chakraborty
Department of Mechanical Engineering, National Institute of Technology Agartala, Tripura 799 046, India
Nabarun Biswas
Department of Production Engineering, National Institute of Technology Agartala, Tripura 799 046, India
Prasun Chakraborti
Department of Mechanical Engineering, National Institute of Technology Agartala, Tripura 799 046, India

Abstract


The newest advancement in the realm of bearing technology, Air Foil Bearings (AFB) is a marvel that allows for operation at both incredibly low and high temperatures without fail. Their minimalistic design eliminates the requirement for lubrication and sealing systems, making them not only more efficient but also more eco-frienadly. When it comes to speed, these bearings give no quarter - they can handle even the most extreme of conditions with ease. Air foil bearings rely on the structural design of top and bump foils to support and distribute pressure in the air film. To increase bearing capacity, these foils must be thick enough to withstand greater force. It is crucial to explore how varying foil thickness and bump height-pitch ratios may affect the performance of an air foil bearing. The researchers at the ANSYS Fluent lab set out to understand the dynamics of air foil bearings. By adjusting the thickness of the top and bump foils, they were able to observe how stress, stiffness, and air film clearance changed in relation to each other. Their results showed that even minor changes in foil thickness, bump height, and bump pitch had a significant impact on bearing performance. With their discoveries, these engineers have unlocked a new understanding of this complex technology - one that will help guide its continued development into the future. The thickness of the foil may not confer much strength, but it certainly does wonders for reducing stress and maintaining load-bearing capabilities. Its suppleness, however, cannot be denied – a boon for air foil bearings.

Keywords


Bump Foil, Foil Thickness, Minimum Air Film Thickness, Top Foil, Unit Stiffness.

References