A compliant foil fluid film thrust bearing including a thrust disk rotor, fluid foils, spring foils, a thrust plate, and a housing thrust surface The non-rotating but compliant fluid foils, mounted on the thrust plate and/or housing thrust surface and positioned adjacent to the thrust disk, have open faced channels that induce regenerative vortex flow patterns in the process fluid. The multiple spring foils together provide a tilting pad support for the fluid foils but allow them to follow the axial and overturning motion of the thrust disk. The interaction of the tilting pad underspring supports and the circumferential fluid pressure gradients in the process fluid between the fluid foils and the thrust disk rotor assure that the fluid foils will assume hydrodynamically efficient convex shapes on the surfaces adjacent to the rotor regardless of the load applied to the thrust bearing.
A compliant foil fluid film bearing having individual fluid film foils formed as arcuate segments by an inner circumferential slot, an outer circumferential slot and a transverse therebetween. The transverse slot may be radial, slightly displaced from radial or tapered with one radial edge.
A compliant foil fluid thrust bearing has a single sided or two sided thrust disk rotor, an integrally formed compliant foil member, and an underspring member. The non-rotating but compliant foils are located adjacent to the thrust face or faces or the rotatable disk and are formed as arcuate segments on washer-shaped disk members. The underspring member consists of three washer-shaped disk elements that together provide variable spring stiffness in both the circumferential and radial directions.
A hydrodynamic bearing set, for use with a thrust disk disposed between planar surfaces of a housing, includes first and second topfoils disposed adjacent first and second thrust disk axial bearing surfaces and removably secured to the housing. An underspring is secured between each planar housing surface and the corresponding topfoil. Dual-leaf spring pairs attached to at least one topfoil periphery function to urge the topfoils away from the thrust disk axial bearing surfaces by applying a force against a planar housing surface, another topfoil, or a spacer washer secured between adjacent topfoil dual-leaf pairs or frictionally retained within the housing. Alternatively, a wavy washer, a conical spring, a Belleville washer, or a coil spring can be substituted for the dual-leaf spring pairs.
A rotor and bearing system for a turbomachine. The turbomachine includes a drive shaft, an impeller positioned on the drive shaft, and a turbine positioned on the drive shaft proximate to the impeller. The bearing system comprises one gas journal bearing supporting the drive shaft between the impeller and the turbine. The area between the impeller and the turbine is an area of increased heat along the drive shaft in comparison to other locations along the drive shaft. The section of the drive shaft positioned between impeller and the turbine is also a section of the drive shaft that experiences increased stressed and load in the turbomachine. The inventive bearing machine system positions only one radial bearing in this area of increased stress and load.
A method and apparatus for starting a turbogenerator having a sensorless magnetic rotor supported for rotation in a stator by a compliant foil fluid film bearing, the method comprising energizing the stator to generate a continuously rotating magnetic field to capture the magnetic rotor and thereafter accelerating the rotational speed of the magnetic field to substantially minimize the time required for the magnetic rotor to reach a liftoff speed associated with the compliant foil fluid film bearing.
