ENG  Vol.9 No.11 , November 2017
The Evolution of Reliability and Efficiency of Aerospace Bearing Systems
Abstract: The worldwide air traffic underwent a rapid development in recent decades. Between the early 70s and the late 90s of the last century civil air traffic doubled every 15 years. The civil aviation market will continue to grow with 4% - 5% each year within the next 20 years. This enormous growth represents major challenges for airframers, engine makers, suppliers, airlines, air traffic management and ground infrastructure. In addition, the public debate on the worldwide civil air traffic is dominated by environmental and climate issues, even though only 2% of the man-made carbon dioxide (CO2) emissions are due to air transportation. Therefore the aerospace industry will have to focus on a low-emission and quite air traffic, and on the conservation of natural resources and our environment. The end-use consumer and environmental policy requirements for aircrafts of the next generation translate into components with improved efficiency and reliability. Rolling bearings are one of these components which significantly determine the reliability and mechanical efficiency of aerospace applications such as aircraft and rotorcraft engines and transmission systems. They have to withstand very demanding operating conditions. Especially main shaft bearings in modern aircraft engines experience high rotational speeds andtemperatures. Furthermore aerospace bearings have to meet the highest reliability standards and require low-weight design solutions. These operating conditions and requirements present a continuous challenge for improvements in all fields of bearing technology. This article presents solutions in aspects of materials, design, analysis, and surface technologies in order to meet the environmental, reliability, and economical requirements of advanced aerospace bearing systems. State of the art bearing analysis and advanced bearing design solutions contributing to lower friction power losses and increased systems efficiency are discussed. Weight, functional, and maintenance benefits are presented with the example of highly integrated aircraft engine main shaft bearings. It is also shown that the progress in bearing materials and surface technology development is the basis for weight and friction energy reduction in aerospace bearing systems.
Cite this paper: Gloeckner, P. and Rodway, C. (2017) The Evolution of Reliability and Efficiency of Aerospace Bearing Systems. Engineering, 9, 962-991. doi: 10.4236/eng.2017.911058.

[1]   Stevenson, D.S., Doherty, R.M., Sanderson, M.G., Collins, W.J., Johnson, C.E. and Derwent, R.G. (2004) Radiative Forcing from Aircraft NOx Emissions: Mechanisms and Seasonal Dependence. Journal of Geophysical Research: Atmospheres, 109, D17307.

[2]   Penner, J.E., Lister, D.H., Griggs, D.J., Dokken, D.J. and McFarland, M. (1999) Aviation and the Global Atmosphere. A Special Report of IPCC Working Groups I and III, 373, Cambridge University Press, Cambridge, UK.

[3]   Gaus, M., Isaksen, I.S.A., Lee, D.S. and Sovde, O.A. (2006) Impact of Aircraft NOx Emissions on the Atmosphere—Tradeoffs to Reduce the Impact. Atmospheric Chemistry and Physics, 6, 1529-1548.

[4]   Rap, A., Forster, P.M., Haywood, J.M., Jones, A., Boucher, O. (2010) Estimating the Climate Impact of Linear Contrails Using the UK Met Office Climate Model. Geophysical Research Letters, 37, L20703.

[5]   Haywood, J.M., Allan, R.P., Bornemann, J., Forster, P.M., Francis, P.N., Milton, S., Radel, G., Rap, A., Shine, K.P. and Thorpe, R. (2009) A Case Study of the Radiative Forcing of Persistent Contrails Evolving into Contrail-Induced Cirrus. Journal of Geophysical Research: Atmospheres, 114, D24201.

[6]   European Commission (2011) Flightpath 2050—Europe’s Vision for Aviation. Report of the High Level Group on Aviation Research.

[7]   Jemitola, P.O. (2012) Conceptual Design and Optimization Methodology for Box Wing Aircraft. PhD Thesis, Cranfield University, UK.

[8]   Bottoni, C. and Scanu, J. (2004) Preliminary Design of a 250 Passenger Prandtl Plane Aircraft. Graduating Thesis, University of Pisa, Pisa.

[9]   Harris, T.A. (2001) Rolling Bearing Analysis. 4th Edition, John Wiley & Sons, Inc., Hoboken.

[10]   Gloeckner, P. (2013) The Influence of the Raceway Curvature Ratio on Power Loss and Temperature of a High-Speed Jet Engine Ball Bearing. Tribology Transactions, 56, 27-32.

[11]   Forster, N., Svendsen, V., Givan, G., Thopmpson, K., Dao, N. and Nicholson, B. (2011) Parametric Testing and Heat Generation Modeling of 133-mm Bore Ball Bearings: Part I—Results with Metal Rolling Elements. Tribology Transactions, 54, 315-324.

[12]   Gupta, P.K. (1984) Advanced Dynamics of Rolling Elements. Springer, Berlin.

[13]   Degtiarev, A., Lenssen, S., Vesselinov, V. and Bakolas, V. (2009) Determination of Fatigue Loads of Complex Systems. 64th STLE Annual Meeting, Lake Buena Vista, FL, 17-21 May 2009.

[14]   Hamrock, B.J. and Dowson, D. (1976) Isothermal Elastohydrodynamic Lubrication of Point Contacts. Part III—Fully Flooded Results. Journal of Lubrication Technology, 99, 264-276.

[15]   Gloeckner, P. and Ebert, F.-J. (2010) Micro-Sliding in High-Speed Aircraft Engine Ball Bearings. Tribology Transactions, 53, 369-375.

[16]   Gloeckner, P., Sebald, W. and Bakolas, V. (2009) An Approach to Understanding Micro Spalling in High Speed Ball Bearings Using a Thermal Elastohydrodynamic Model. Tribology Transactions, 52, 534-543.

[17]   Salpistis, C., Mihailidis, A., Drivakos, N. and Gatsios, S. (2006) Experimentally Obtained Solid Contact Time Curves as Criterion of the EHL Performance of Rough Surfaces. The 2nd International Conference “Power Transmission 06”, Novi Sad, 25-26 April 2006, 347-350.

[18]   Ebert, F.J. and Poulin, P. (1995) The Effect of Cleanliness on the Attainable Bearing Life in Aerospace Applications. Tribology Transactions, 38, 851-856.

[19]   Boehmer, H.J., Ebert, F.J. and Trojahn, W. (1991) M50NiL Bearing Material—Heat Treatment, Material Properties and Performance in Comparison with M50 and RBD. 46th STLE Annual Meeting, Montreal, Canada, 29 April-2 May 1991, Preprint No. 91-AM-3G-2

[20]   Broszeit, E. and Zwirlein, O. (1986) Internal Stresses and Their Influence on Material Stresses in Hertzian Contacts—Calculations with Different Stress Hypothesis. Journal of Tribology, 108, 387-393.

[21]   Schlicht, H. and Zwirlein, O. (1980) Werkstoffanstrengung bei Walzbeanspruchung—Einflup von Reibung und Eigenspannungen. Materialwissenschaft und Werkstofftechnik 11, 1-14.

[22]   Boehmer, H., Loesche, T., Ebert, F.J. and Streit, E. (1999) The Influence of Heat Generation in the Contact Zone on Bearing Fatigue Behavior. Journal of Tribology, 121, 462-467.

[23]   Streit, E., Brock, J. and Poulin, P. (2006) Performance Evaluation of “Duplex Hardened” Bearings for Advanced Turbine Engine Applications. Journal of ASTM International, 3.

[24]   Ebert, F.-J. (1990) Performance of Silicon Nitride (Si3N4) Components in Aerospace Bearing Applications. Proceedings of the Gas Turbine and Aeroengine Congress and Exposition, The American Society of Mechanical Engineers, Brussels, 11-14 June 1990, 90-GT-166.

[25]   Gloeckner, P., Martin, M. and Flouros, M. (2017) Comparison of Power Losses and Temperatures between an All-Steel and a Direct Outer Ring Cooled, Hybrid 133 mm Bore Ball Bearing at Very High Speeds. Tribology Transactions, 60, 1148-1158.

[26]   Streit, E., Trojahn, W., Chin, H.A. and Ehlert, D. (1999) Progress in Bearing Performance of Advanced Nitrogen Alloyed Stainless Steel, Cronidur 30. Materialwissenschaft und Werkstofftechnik, 30, 605-611.<605::AID-MAWE605>3.0.CO;2-V

[27]   Gloeckner, P., Dullenkopf, K. and Flouros, M. (2011) Direct Outer Ring Cooling of a High Speed Jet Engine Mainshaft Ball Bearing. Journal of Engineering for Gas Turbines and Power, 133, 062503-1-7.

[28]   Glockner, P. (2009) Advanced Bearing Technologies for Aerospace Power Systems. Proceedings of the 3rd International Conference “Power Transmission’09”, Chalkidiki, 427-434.