Rotor-Bearing System Stability Performance Comparing Hybrid versus Conventional Bearings
<p>New closed-form expressions for calculating the linear stability thresholds for rigid and flexible Jeffcott systems and the imbalance response for a rotor supported on a hybrid bearing are presented. For typical bearings characteristics, expressions yield stability thresholds practically eq...
Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2005-01-01
|
| Series: | International Journal of Rotating Machinery |
| Subjects: | |
| Online Access: | http://www.hindawi.net/access/get.aspx?journal=ijrm&volume=2005&pii=S1023621X04502099 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850169995781210112 |
|---|---|
| author | Gomez-Mancilla Julio Nosov Valeri Silva-Navarro Gerardo |
| author_facet | Gomez-Mancilla Julio Nosov Valeri Silva-Navarro Gerardo |
| author_sort | Gomez-Mancilla Julio |
| collection | DOAJ |
| description | <p>New closed-form expressions for calculating the linear stability thresholds for rigid and flexible Jeffcott systems and the imbalance response for a rotor supported on a hybrid bearing are presented. For typical bearings characteristics, expressions yield stability thresholds practically equal to those reported by Lund (1966). The hybrid bearing design has a single injection port whose location is so chosen to stabilize the bearing performance and to reduce the steady equilibrium attitude angle. Rotordynamics coefficients graphs for conventional and pressurized bearings, as functions of bearing equilibrium eccentricity and/or Sommerfeld number, are presented. Using the rotordynamics coefficients into the expressions for the corresponding velocity thresholds and the imbalance response, the system stability and vibration performances are estimated and analyzed. When comparing the Jeffcott flexible shaft supported on two journal bearings of the conventional type with the hybrid type, the results show a clear superiority of the pressurized design as far as stability behavior is concerned. Specifically for cases of flexible shafts with similar characteristics to those used in industry, the analysis shows that this design yields velocity thresholds 25%–40% higher compared to the conventional circular ones. Also this bearing displays nonlinear feeding pressure behavior, and it is capable of reducing the synchronous vibration amplitude in most speed ranges, except around the critical speed; moreover, for certain Jeffcott configurations the amplitude reduction can be substantial.</p> |
| format | Article |
| id | doaj-art-ad2a6600443445ecb7e494f2f14e06f4 |
| institution | OA Journals |
| issn | 1023-621X |
| language | English |
| publishDate | 2005-01-01 |
| publisher | Wiley |
| record_format | Article |
| series | International Journal of Rotating Machinery |
| spelling | doaj-art-ad2a6600443445ecb7e494f2f14e06f42025-08-20T02:20:36ZengWileyInternational Journal of Rotating Machinery1023-621X2005-01-01200511622Rotor-Bearing System Stability Performance Comparing Hybrid versus Conventional BearingsGomez-Mancilla JulioNosov ValeriSilva-Navarro Gerardo<p>New closed-form expressions for calculating the linear stability thresholds for rigid and flexible Jeffcott systems and the imbalance response for a rotor supported on a hybrid bearing are presented. For typical bearings characteristics, expressions yield stability thresholds practically equal to those reported by Lund (1966). The hybrid bearing design has a single injection port whose location is so chosen to stabilize the bearing performance and to reduce the steady equilibrium attitude angle. Rotordynamics coefficients graphs for conventional and pressurized bearings, as functions of bearing equilibrium eccentricity and/or Sommerfeld number, are presented. Using the rotordynamics coefficients into the expressions for the corresponding velocity thresholds and the imbalance response, the system stability and vibration performances are estimated and analyzed. When comparing the Jeffcott flexible shaft supported on two journal bearings of the conventional type with the hybrid type, the results show a clear superiority of the pressurized design as far as stability behavior is concerned. Specifically for cases of flexible shafts with similar characteristics to those used in industry, the analysis shows that this design yields velocity thresholds 25%–40% higher compared to the conventional circular ones. Also this bearing displays nonlinear feeding pressure behavior, and it is capable of reducing the synchronous vibration amplitude in most speed ranges, except around the critical speed; moreover, for certain Jeffcott configurations the amplitude reduction can be substantial.</p>http://www.hindawi.net/access/get.aspx?journal=ijrm&volume=2005&pii=S1023621X04502099Jeffcott rotorhybrid bearingimbalance responsepressurized rotordynamics coefficientsstability threshold |
| spellingShingle | Gomez-Mancilla Julio Nosov Valeri Silva-Navarro Gerardo Rotor-Bearing System Stability Performance Comparing Hybrid versus Conventional Bearings International Journal of Rotating Machinery Jeffcott rotor hybrid bearing imbalance response pressurized rotordynamics coefficients stability threshold |
| title | Rotor-Bearing System Stability Performance Comparing Hybrid versus Conventional Bearings |
| title_full | Rotor-Bearing System Stability Performance Comparing Hybrid versus Conventional Bearings |
| title_fullStr | Rotor-Bearing System Stability Performance Comparing Hybrid versus Conventional Bearings |
| title_full_unstemmed | Rotor-Bearing System Stability Performance Comparing Hybrid versus Conventional Bearings |
| title_short | Rotor-Bearing System Stability Performance Comparing Hybrid versus Conventional Bearings |
| title_sort | rotor bearing system stability performance comparing hybrid versus conventional bearings |
| topic | Jeffcott rotor hybrid bearing imbalance response pressurized rotordynamics coefficients stability threshold |
| url | http://www.hindawi.net/access/get.aspx?journal=ijrm&volume=2005&pii=S1023621X04502099 |
| work_keys_str_mv | AT gomezmancillajulio rotorbearingsystemstabilityperformancecomparinghybridversusconventionalbearings AT nosovvaleri rotorbearingsystemstabilityperformancecomparinghybridversusconventionalbearings AT silvanavarrogerardo rotorbearingsystemstabilityperformancecomparinghybridversusconventionalbearings |