The desire to increase power density and reduce fuel consumption for future turboshaft engines necessitates higher overall cycle operating pressures and temperatures. This results in higher shaft speeds and the need for high bearing DN capability. Oil-free compliant foil bearing technology tolerates very high shaft rpms (high bearing DN) where traditional oil lubricated rolling element bearings have limited durability and life due to high contact stress, inner ring hoop stresses and dynamic loading between the rolling elements and the separating cage. Increased temperatures and pressures also make lubrication supply and scavenge increasingly difficult in small high performance turbine engines. Early foil bearing designs with basic "first generation" compliant support elements have relatively low load capacity. Recent improvements in design of the compliant foil structure based on elastic and hydrodynamic modeling have allowed demonstration of significant increases in load capacity. Compliant foil bearings have significantly higher speed and temperature capability relative to rolling element bearings. These bearings develop respectable load bearing capacity and since they are self-pumping, use very little secondary air flow (which is used for thermal management). Since load carrying capacity of foil bearings increases with operating speed and air density, these bearings are ideal for advanced small turboshaft engines which have lower weight rotors operating at very high rotational speeds. This paper describes a cooperative program funded by the Army Aviation Applied Technology Directorate (AATD) and General Electric Aircraft Engines (GEAE), where GEAE and AATD have teamed with R&D Dynamics, a world recognized leader in the development of foil bearing technology, to design, develop and fabricate compliant foil bearings for oil free operation in advanced turboshaft engines such as GEAE's Advanced Affordable Turbine Engine (AATE) and to demonstrate technology suitable for transition into product via rig and engine testing.
Application of compliant foil air bearings for oil free operation of advanced turboshaft engines
2006
6 Seiten, 1 Quelle
Conference paper
English
Application of Compliant Foil Air Bearings for Oil Free Operation of Advanced Turboshaft Engines
British Library Conference Proceedings | 2006
|Advanced Fuel Control System for Turboshaft Engines
British Library Conference Proceedings | 1996
|Turboprop and Turboshaft Engines
Springer Verlag | 2012
|Compliant Gas Foil Bearings and Analysis Tools
Online Contents | 2016
|Evolution of Small Turboshaft Engines
SAE Technical Papers | 1972
|