Investigation of Structural Conformity in a Three-Pad Adaptive Air Foil Bearing With Regard to Active Control of Radial Clearance

Various solutions for the design of oil-free bearings are discussed in the literature. Adding hydrodynamic preload to the foil bearings by profiling the inner bore of the bearing is one of the most frequently investigated methods for improving the bearing stability and damping character of the entire system. However, this approach leads to a reduced …

Investigation of Structural Conformity in a Three-Pad Adaptive Air Foil Bearing With Regard to Active Control of Radial Clearance

Various solutions for the design of oil-free bearings are discussed in the literature. Adding hydrodynamic preload to the foil bearings by profiling the inner bore of the bearing is one of the most frequently investigated methods for improving the bearing stability and damping character of the entire system. However, this approach leads to a reduced …

IYPT 2019 Elements 032: Germanium: Camera lenses and guitar effects pedals

Element 32 in our International Year of the Periodic Table series is germanium. Found in some camera lenses and guitar effects pedals, it’s also present in some LCD TVs. Germanium oxide has a high index of refraction, meaning light travels through it particularly fast. This gives it applications in wide angle lenses for cameras and microscope …

IYPT 2019 Elements 032: Germanium: Camera lenses and guitar effects pedals

Element 32 in our International Year of the Periodic Table series is germanium. Found in some camera lenses and guitar effects pedals, it’s also present in some LCD TVs. Germanium oxide has a high index of refraction, meaning light travels through it particularly fast. This gives it applications in wide angle lenses for cameras and microscope …

Elastohydrodynamic Lubrication Modeling by a Cosserat Continuum Theory for Small Polymer Journal Bearings

Recent experiments have shown that the elastic deformation behaviors of a polymeric material are consistent with the Cosserat elasticity under nonuniform deformation at a millimeter scale. Thus, an elastohydrodynamic lubrication model in the framework of the Cosserat continuum theory is proposed to explore the lubrication performance that deviates from the classical elastohydrodynamic lubrication theory for …

Effects of Ni-Coated Graphite Flake on Braking Behavior of Cu-Based Brake Pads Applied in High-Speed Railway Trains

Cu-based brake pads applied in high-speed railway trains containing Ni-coated graphite flake and uncoated graphite flake were fabricated by powder metallurgy. The braking properties of the brake pads were investigated by a scaled down testing apparatus with the pad-on-disk configuration under various braking speeds and braking pressures. Compared with the brake pads containing uncoated graphite …