Abstract: A turbocharger system can include a housing that includes a bore defined at least in part by a bore wall; a rolling element bearing unit that includes an outer race; and a mixed-element damper assembly disposed at least in part between the outer race and the bore wall where the mixed-element damper assembly includes a lobed-spring element and a squeeze film damper element.

Abstract: A turbocharger system can include a housing that includes a bore defined at least in part by a bore wall; a rolling element bearing unit that includes an outer race; and a mixed-element damper assembly disposed at least in part between the outer race and the bore wall where the mixed-element damper assembly includes a lobed-spring element and a squeeze film damper element.

Abstract: The present invention provides apparatus and methods for balancing stacked components of rotating machinery, such as in a gas turbine engine. Unlike conventional processes and devices for balancing stacked components, the present invention may use a single non-parallel spacer for obtaining an acceptable and repeatable component group balance. The non-parallel spacer may be used to compensate for rotor bow and the associated imbalance of the rotor group. By indexing a spacer with non-parallel faces, situated terminally at the end of the stack adjacent to the nut, rotor balance can be achieved without disassembly of the rotor group and clocking of its individual components. A spacer may also be disposed at any one or more of the interfaces between various components in the stack.

Abstract: The present invention provides a centering feature to the bearing assembly of a turbomachine to provide optimum operating characteristics of the squeeze film damper. Unlike conventional bearing centering methods and apparatus, a compact compliant centering support for the squeeze film damper interfaces between a bearing outer race, and an outer support structure. The compact design is lightweight and inexpensive, can be retrofitted easily to an existing turbomachine, such as a turbine and compressor, for improved rotor dynamic performance. The compact compliant centering support damper may be comprised of a ring with bumpers spaced around the circumference at the inside and outside diameters to form spring elements between the bumpers. The centering support may lift the rotor inside the squeeze film cavity and may eliminate rotor weight effect on the damper performance.