A Gas Turbine Engine Backup Bearing Operating Beyond 2.5 Million DN

Author(s):  
Erik Swanson ◽  
James F. Walton ◽  
Hooshang Heshmat

Gas turbine engines and high speed rotating machinery using magnetic bearings require auxiliary and backup bearings for reliability and safety of operation. A 140 mm diameter Zero Clearance Auxiliary Bearing (ZCAB) capable of supporting radial and/or thrust loads of up to 4500 N was designed for an advanced gas turbine engine. The ZCAB was fabricated and tested successfully up to the expected maximum operating speed of 18,000 rpm in a specially configured test rig. The test rig included a 36,000 rpm capable drive motor, a 64 kg rotor which simulates a gas turbine engine shaft dynamics, a damped ball bearing at the drive end and an active magnetic bearing next to the ZCAB. Operation in excess of 240 minutes and 20 transient engagements simulating magnetic bearing failures were completed in the initial tests. Post test inspection revealed minimal wear to the shaft and the ZCAB rollers, whereupon the ZCAB was reassembled for shipment. These preliminary tests confirm the operation and durability of the ZCAB in maintaining rotor support and continued operation even if the primary magnetic bearing support is overloaded or encounters a failure.

Author(s):  
D. M. Croker ◽  
T. P. Psichogios

This paper describes the operation and salient design features of a high-speed reversing gear used with the Solar 1100-hp Saturn gas-turbine Engine. Development history leading to successful marine applications is reviewed.


2017 ◽  
Vol 139 (4) ◽  
Author(s):  
Yulan Zhao ◽  
Guojun Yang ◽  
Patrick Keogh ◽  
Lei Zhao

Active magnetic bearings (AMBs) have been utilized widely to support high-speed rotors. However, in the case of AMB failure, emergencies, or overload conditions, the auxiliary bearing is chosen as the backup protector to provide mechanical supports and displacement constraints for the rotor. With lack of support, the auxiliary bearing will catch the dropping rotor. Accordingly, high contact forces and corresponding thermal generation due to mechanical rub are applied on the dynamic contact area. Rapid deterioration may be brought about by excessive dynamic and thermal shocks. Therefore, the auxiliary bearing must be sufficiently robust to guarantee the safety of the AMB system. Many approaches have been put forward in the literature to estimate the rotor dynamic motion, nonetheless most of them focus on the horizontal rotor drop and few consider the inclination around the horizontal plane for the vertical rotor. The main purpose of this paper is to predict the rotor dynamic behavior accurately for the vertical rotor drop case. A detailed model for the vertical rotor drop process with consideration of the rotating inclination around x- and y-axes is proposed in this paper. Additionally, rolling and sliding friction are distinguished in the simulation scenario. This model has been applied to estimate the rotor drop process in a helium circulator system equipped with AMBs for the 10 MW high-temperature gas-cooled reactor (HTR-10). The HTR-10 has been designed and researched by the Institute of Nuclear and New Energy Technology (INET) of Tsinghua University. The auxiliary bearing is utilized to support the rotor in the helium circulator. The validity of this model is verified by the results obtained in this paper as well. This paper also provides suggestions for the further improvement of auxiliary bearing design and engineering application.


2014 ◽  
Vol 51 (3) ◽  
pp. 208-215
Author(s):  
E. Cagliyan ◽  
T. Gädicke ◽  
A. Neidel

1980 ◽  
Vol 52 (6) ◽  
pp. 21-22

The modern aircraft gas turbine engine produces power on demand hour upon hour and day in, day out. It is one of the most extensively used types of high‐speed rotating machinery as well as one of the most efficient converters of fuel into thrust. Reliability and long life with minimum maintenance depend on efficient monitoring of engine performance and component status.


1973 ◽  
Vol 95 (4) ◽  
pp. 401-416 ◽  
Author(s):  
J. H. Rumbarger ◽  
E. G. Filetti ◽  
D. Gubernick

An interdisciplinary systems analysis is presented for high-speed gas turbine engine mainshaft roller bearings which will enable the designer to meet the demands for ever higher rotative speeds and operating temperatures. The latest elastohydrodynamic experimental traction data are included. Analytical results cite a need for better definition of the rolling friction portion of the total traction. A fluid mechanics model for the detailed analysis of fluid drags is developed based upon a turbulent vortex-dominated flow and includes the effect of lubricant flow through the bearing. A complete thermal analysis including dynamic and thermal effects upon bearing dimensions and resulting clearances is also included. Heat transfer coefficients are given in detail. Shaft power loss and cage slip predictions as a function of load, speed, and lubricant supply correlate well with available experimental data.


Author(s):  
Gerrit A. Kool ◽  
Arjen B. Kloosterman ◽  
Edward R. Rademaker ◽  
Bambang I. Soemarwoto ◽  
Fons M. G. Bingen ◽  
...  

Advanced seals have been identified as critical in meeting engine goals for specific fuel consumption, thrust-to-weight ratio, emissions, durability, and operating costs. In a direct effort to reduce the parasitic leakage, a high-temperature, high-speed seal test rig with Active Clearance Control (ACC) has been designed, built and validated by the National Aerospace Laboratory (NLR) in the Netherlands within a collaborative program with Sulzer Metco Turbine Components (SMTC) and Pratt & Whitney (P&W). NLR’s new seal test rig is capable to evaluate seals for the next generation gas turbine engines. It will test air seals (i.e., labyrinth, brush, and new seal concepts) in near gas turbine engine environment conditions of high temperature to 815 °C (1500 °F), high pressure to 2400 kPa (335 psid), high surface speeds to 365 m/s (1200 ft/s). Seal flows for typical engine seal clearances between 0.12 mm (0.005 inch) and 0.65 mm (0.025 inch) can be measured without changing test articles but by using the ACC system. A compressed air facility at the German-Dutch Windtunnel, located at the NLR site, delivers the required compressed clean and dry air. This paper describes the design, the instrumentation, the control system and the validation of the test rig. The rig certification was achieved by validating test measurements using a known three knife-edges stepped labyrinth seal. This paper also addresses the NLR’s CFD and engineering tool development to predict the seal performance.


Author(s):  
Oscar De Santiago ◽  
Víctor Solórzano ◽  
Sergio Díaz

Recent challenges in turbocompresor design include applications in subsea installations as well as remote operation in unmanned floating platforms. These applications benefit from oil-free operation which solves technical hurdles while being environmentally friendly. The most mature oil-free rotor support technology today is the magnetic bearing which is being used by several manufacturers as their standard solution to these advanced applications. These systems require auxiliary bearings to contain the rotor in case of a power failure to the magnetic bearings or a transient event. In general, there exists the need to develop commercial solutions for auxiliary bearings to extend its life, in particular regarding cumulative damage associated to drop events. This paper presents the design of a configurable test rig that can accommodate different rotor sizes, up to 1200 mm in bearing span, and 711 mm diameter wheels. The rig can also accommodate bearing sizes up to 229 mm. Rig pedestals can fit different bearing types such as magnetic bearings and/or auxiliary bearings independently, including oil bearings for comparison purposes. Misalignment and support flexibility effects are also possible. A 15.5 kW, variable speed electric motor drives the test rotor up to a speed limit of 10,000 rpm. Initial experiments on auxiliary bearings are shown for a 5-impeller, 57.8 kg, subcritical compressor rotor without drop events to study the baseline dynamic behavior of roller-element bearings (with inner clearance) on soft supports (o-rings). These experiments are presented to illustrate non-linear vibration regimes present during rotor-stator interaction with a highly unbalanced rotor. Experimental evidence presented can be used to fine-tune current auxiliary bearingmodels to improve rotordynamic predictive codes.


Author(s):  
B. M. Antkowiak ◽  
F. C. Nelson

This paper summarizes the development of a finite element rotordynamic solution used in a closed loop simulation for a magnetic bearing rotor system in a gas turbine engine. A magnetic bearing controlled rotor is analyzed, and the state dynamics matrix [A], the shaft control influence matrix [B], and the sensor matrix [C] are constructed. Bode plots of the state-space transfer function are also constructed and compared to the results of the rotor dynamic model.


1966 ◽  
Vol 3 (01) ◽  
pp. 42-48
Author(s):  
D. M. Croker ◽  
T. P. Psichogios

This paper describes the operation and salient design features of a high-speed reversing gear used with the Solar 1100-hp Saturn gas-turbine engine. Development history leading to successful marine applications is reviewed.


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