Phone: (979) 862 4744 Fax: (979) 845 6382
Tribology Group/Rotordynamics Laboratory
is one of the most active and well equipped research groups in the
Turbomachinery Program at
In the field of Tribology (friction, lubrication and wear) research focuses on experimentally verified computational film flow models for the prediction of the static and dynamic force response of fluid film bearings; in particular hydrostatic bearings, tilting pad bearings, annular pressure seals, squeeze film dampers, floating ring bearings, and gas damper bearings and seals.
In the Rotordynamics
field, research deals with the measurement and prediction of the dynamic
lateral vibration characteristics of turbomachinery, encompassing both the
traditional aspects of rotordynamics analysis and investigations into the fluid
film-structure interaction forces that influence rotordynamics, with a major
emphasis in fluid film dampers and gas bearings.
Annual Progress Reports (May)
Download short (pdf) reports describing major achievements, publications and funding
Slide shows for technical presentations
For potential sponsors
2014 Machinery Vibrations and Rotordynamics Short Course, January 13-17 2014
2013 TurboExpo13: Foil
Bearings, Metal Mesh Bearings, Tilting Pad Bearings, SFDs.
STLE Annual Meeting: Laby vs HALO seal, open ends SFD.
2013 TRC Meeting: presentations and proposals to sponsors.
INVITATION: SHORT COURSE Date: April 16-17,
2013, Tuition: $1,350.00, CEU Credits: 16.
Gas Foil Bearings for Rotating Machinery
An introduction to the operation, design and performance of gas foil bearings and their practical integration into oil-free turbomachinery.
Instructors: Luis San Andrés and
Daniel Lubell (Calnetix)
2012 TurboExpo12: Foil Bearings, Metal Mesh Bearings, SFDs, Turbochargers and more.
2012 TRC Meeting: presentations and proposals to sponsors.
2011 TurboExpo11: Foil
Bearings, SFDs, and more. Turbochargers, Congreso Latinoamericano de Turbomaquinaria.
2011 TRC Meeting: presentations and proposals to sponsors.
2010 Turbo Expo10: Hot Foil Bearings, Metal Mesh Bearings, IFToMM: Turbochargers, foil bearings
No TRC projects were funded in 2010 (Dr. San Andres on Faculty Development Leave)
2009 Turbo Expo 09: Foil Bearings, Metal Mesh Bearings, SFDs
2009 Metal mesh foil bearings at EPN (July 2009) Quito-Ecuador
TRC funded projects (May 09)
DYNAMIC RESPONSE OF A ROTOR-AIR BEARING SYSTEM DUE TO BASE INDUCED PERIODIC MOTIONS
Measurements of Rotordynamic Performance in a Hot Rotor-Gas Foil Bearing System
Measurement of Bearing Drag Torque, Lift-Off Speed and Identification of Structural Stiffness and Damping in a Metal Mesh Foil Bearing
2008 ISCORMA -2008 Plenary Lecture on
TRC funded projects (May 08)
Dynamic Performance of a Squeeze Film Damper with Non-Circular Motions: Multi-Frequency Excitations Reproducing Multi-Spool Engine Operating Conditions
A Novel FE Lubrication Model for Improved Predictions of Force Coefficients in Off-Centered Grooved Oil Seals
Dynamic Forced Response of a Rotor-Hybrid Gas Bearing System due to Intermittent Shocks
Thermohydrodynamic Analysis of Bump Type Gas Foil Bearings: Model and Predictions & Rotordynamic Measurements on a High Temperature Rotor Supported on Gas Foil Bearings
Development of a Test Rig for Metal Mesh Foil Gas Bearing and Measurements of Structural Stiffness and Damping in a Metal Mesh Bearing
The Effect of (Nonlinear) Pivot Stiffness on Tilting Pad Bearing Dynamic Force Coefficients
Simplified Thermohydrodynamic Analysis of (rigid geometry) Journal Bearings
GOALS of our RESEARCH GROUP
To provide an
advanced education in the fields of fluid film lubrication and rotordynamics
Our goal is to provide both graduate and undergraduate students with an in-depth education on the fundamental aspects of fluid film bearing technology and dynamics of high speed rotating machinery. Our current research covers a wide spectrum of novel bearing and seal applications and rotordynamics addressing to current and future industrial needs
To develop advanced
analytical and computational tools for the analysis and design of process fluid
The trends in turbomachinery demand the largest output power to weight ratios and require flexible mechanical rotating components able to operate at increased speeds, temperatures and pressure differentials. Best efficiency and compactness can only be achieved with the effective use of the process liquid or gas as the lubricant in the support bearings
To procure experimental measurements of the static and
dynamic force performance of fluid film bearings and squeeze film dampers for
Our experimental research program on squeeze film dampers has an outstanding international reputation. Major advances have resulted from the analysis and experimental verification of the forced performance of squeeze film dampers due to the effects of feeding grooves, fluid inertia and dynamic lubricant cavitation. The latest experimental measurements provide fundamental understanding on the complex flow mechanics of air ingestion and entrapment (bubbly lubricant mixtures) in the dynamic performance of squeeze film dampers
To advance technologies for oil-free turbomachinery and
Current research focuses on the analysis and experimental verification of the static and dynamic forced performance of gas bearings and seals for applications in micro-turbomachinery (40 Kw-500 kW) and portable power hybrid systems (SFOC & gas turbines).
· SSV-Free Tilting Pad Bearings s
Objective: Model Tilting Pad Bearing Dynamics and Prediction of pad natural frequencies and onset of sub-synchronous vibrations.
Status: Predictive tool under development and validation to published test data.
Sponsor : Hitachi RC, Project started September 1, 2013 (1 year).
· Thrust foil bearings for oil-free turbochargers
Objective: Model FE code for prediction of dynamic forced response of bump-type thrust foil bearings.
Status: Predictive tool under development and validation to published test data.
Sponsor : Borg-Warner Turbo, $90,441 Project started September 1, 2011 (1 year).
· Squeeze Film Damper – Identification of dynamic forced performance
Objective: To assess novel SFD designs for aircraft applications.
Status: Test rig operational (500 lbf dynamic force). Measurements and force coefficients identification completed in a 5” OD open ends SFDs with central groove. Effect of fluid inertia dominates SFD forced response.
Sponsor: Pratt & Whitney Engines, $160k January 1, 2012-December 21, 2013 (2 year).
Turbomachinery Research Consortium, $86 k January 1, 2012-May 2014 (2 year).
· Thermal Energy Transport Analysis for (Semi) Floating Ring Bearings in Turbochargers
Objective: Integrate thermal energy transport for prediction of forced response in turbocharger bearings
Status: Completed code for semi-floating ring bearings. Validations with test data awaiting.
Sponsor : Honeywell Turbocharging technologies, $208,340 Project started October 1, 2010 (2 years).
· Metal mesh foil bearings (MMFB) for high speed turbomachinery
Objective: Continue to advance gas bearing technology for high temperature, high speed microturbomachinery applications (power < 400 kW).
Status: Completed tests to verify performance of MMFB at high temperature(200 C) & rotor speed (50 krpm)
Sponsor: Turbomachinery Research Consortium, $38,608 Project started Dec 1, 2011 (1 year).
· Measurement of leakage in a novel all-metal non-contacting annular seal at high temperature
Objective: revamp high temperature gas seal test rig for high speed operation and to measure leakage for a labyrinth seal and a HALOTM seal
Status: Completed leakage measurements w/o rotor spinning. Revamping of rig for high speeds in the works.
Sponsor : Turbomachinery Research Consortium, $74,863 Project started September 1, 2010 (2 years).
· Computational Model for Tilting Pad Journal Bearings
Objective: Develop code for prediction of tilting pad bearings forced response accounting for thermal effects and including pivot radial and transverse flexibility.
Status: Completed. TPJB© code shows +good correlation with test data for bearings with very flexible pivots.
Sponsor: Turbomachinery Research Consortium, $70,421 Project start September 1, 2010 (2 years).
· Automated Analysis of XLTRC2 Time Transient Responses in Nonlinear Rotor Bearing Systems
Objective: Modeling of NL rotor-bearing systems and GUIs for data handling of XLTRC2 nonlinear transient rotor response output data.
Status: GUIs developed for automated analyses with minimum User interaction. Applications sought
Sponsor: Turbomachinery Research Consortium, $34,863 Project start May 1, 2011 (2 year).
· Computational Model for Textured Surface Gas Face Seals
Objective: Develop code for leakage and forced response in textured gas face seals for steam turbines.
Status: Code SpiralG extended to model T groove textured surfaces and GUI completed. Start Sept 1, 2011
Sponsor : Ciateq A.C. (Mx),
OTHER COMPLETED PROJECTS
· Gas Bearings for Oil-Free Turbomachinery TRC-B&C-1-09
Objective: To advance the technology of inexpensive reliable gas bearings for micro gas turbines and micro power systems
Status: Demonstrated reliability of hybrid gas bearings to intermittent shocks and shaker induced excitations into base of test rotor-bearing system.
Sponsors: TRC (Turbomachinery Research Consortium)
· Metal Mesh Foil Bearings for Microturbomachinery TRC-B&C-3-09, TRC-B&C-1-10
Objective: Further development of predictive models anchored to test data for prediction of mechanical parameters of metal mesh foil bearings.
Status: high speed ( 60 krpm) test rig completed. Measurements of bearing lift off and drag torque during start up and shut down obtained. In 2010, measurements of metal mesh bearing force coefficients completed.
Sponsor: TRC (2007-2009), test rig donated by Honeywell Turbocharging Technologies
· Foil Gas Bearings for Oil-Free Turbomachinery TRC-B&C-2-09
Objective: To quantify the structural and dynamic forced performance of bump type foil gas bearings for high temperature micro turbine applications
Status: Computational analysis complete to model thermal management of foil bearings. High temperature test rig (max 400 C) in operation: MiTi Korolon® bearings and Foster-Miller bearings. Cooperation with KIST Korean Institute of Science and Technology).
Sponsors: NSF (2004-2006), NaSA GRC
(2007-2009), TRC (2004-2008)
· Hybrid Brush Seals to Improve Gas Turbine Efficiency
Objective: Measurements of leakage, power loss and structural parameters in labyrinth seal, brush seal and hybrid brush seals for gas turbine applications
Status: High temperature (300 C) test rig operational. Comparisons of leakage measurements in labyrinth seal, brush seal, hybrid brush seal completed. Tests with novel HALO® seal in progress. Hybrid brush seals have 1/15 less leakage than labyrinth seal and 1/3 less than conventional brush seal.
Sponsor: Siemens Power Generation (2006-2009), Seals from Advanced Turbomachinery Group (ATG)
· Dynamic Force Performance of Squeeze Film Dampers
Objective: To assess effect of mechanical end seal on dynamic forced performance of a test SFD.
Status: Test rig accommodates a SFD with a (non rotating) mechanical seal that adds dry friction to system while containing lubricant for extended periods of time and without side leakage. Seal design most successful to avoid air ingestion and entrapment. Structural, dry-friction parameter of mechanical seal and squeeze film damper damping and inertia coefficients identified from single frequency load tests forcing unidirectional and circular centered orbits. Predicted SFD force coefficients agree well with measured ones.
Sponsor: TRC 2004-2009
· Nonlinear Rotordynamics of Automotive Turbochargers: Computational Analysis of Floating Ring Journal Bearings (FRBs) and Experimental Validation in a Turbocharger Test Rig
Objective: To advance (experimentally validated) computational tools for prediction of the dynamic forced response of turbocharger rotors supported on FRBs.
Status: Virtual Laboratory (computational software) is a production tool at Honeywell.
Research continues to model compressor and turbine aerodynamic forces and more
complex bearing geometries. Advice on foundation model to
Sponsor: Honeywell Turbo Technologies 2001-2008
· CLIN 004 - Tool/Method Development of the AFRL Upper Stage Technology Program (USET) Turbopump USET Development
Objective: Experimental validation and enhancements of computational models for prediction of dynamic forced performance of cryogenic liquid hydrostatic bearings - USAF Upper Stage Engine Technology Program.
(a): To develop hydrostatic bearing tool with capability for modeling the non-linear forced response of fluid film bearing, i.e. bearing reaction forces (impedance models) as a function of instantaneous journal position, velocity and acceleration
(b): Create capability for modeling speed dependent non-linear operation in mixed flow regime (fluid and solid contact), including prediction of lift-off speed
(c): Experimental Study of Hydrostatic / Hydrodynamic Thrust Bearings: 25 krpm, 250 psi, 600 lbf, water bearings.
Sponsor: Northrop Grumman 2005-2008
To develop procedures for practical on site reliable bearing parameter identification techniques
Dr. Luis San Andrés, Professor & Group
ASME Fellow, STLE Fellow, Mast-Childs Tribology Professor
Dr. San Andrés has an international reputation as a qualified analyst and experimentalist in the fields of fluid film lubrication and rotordynamics. Dr. San Andrés has managed research projects with a total value exceeding 7 million dollars. He directs a laboratory with an average of seven fully supported research assistants per year. Dr. San Andrés has educated many graduate students currently practicing their skills and providing services and leadership to turbomachinery manufacturers. Dr. San Andrés and his students have published extensively in the archival literature: 127 peer reviewed journal papers, 55 reviewed and 40 invited conference papers, 100+ technical reports. Dr. San Andrés also holds five patents and the copyright for various computational programs predicting the performance of liquid and gas hydrostatic and hydrodynamic bearings, seals and foil gas bearings.
Dr. San Andrés has provided major advances to the technology of hybrid bearings (hydrostatic / hydrodynamic) for applications in primary power space turbopumps. The bearings investigated, both theoretically and experimentally, include flexure-pivot tilting pad bearings, angled injection hybrid bearings and foil-bearings. Current research interests include analysis of hybrid thrust bearings and two-phase fluid seals for cryogenic applications, and high speed gas face seals and bearings with enhanced damping characteristics.
The Tribology Group has developed advanced and
efficient computational models for the analysis and design of process-fluid
film bearings (hydrostatic and hydrodynamic), gas bearings including foil
bearings, gas damper and labyrinth seals, tilting pad bearings and squeeze film
dampers. The thermo hydrodynamic flow models account for fluid inertia and
variable properties, flow turbulence in exotic bearing geometries. Applications
to high-speed turbomachinery include cryogenic turbopumps, aircraft jet
engines, industrial compressors, etc. Users include Boeing-Rocketdyne, Pratt
Distinctions – Former
ASME Tribology Division
2013 Burt Newkirk Investigator Award
Foil Gas Bearings
Deborah Osborne- Wilde
ASME Tribology Division
2004 Marshal Peterson Young Investigator Award
Gas Bearings and Seals
ASME Tribology Division
2003 Burt Newkirk Investigator Award
Squeeze Film Dampers
1998 Outstanding Graduate Student Award
Gas Annular and Face Seals
Several graduate and undergraduate students have obtained STLE scholarships and fellowships
2012 Best Paper Award, Microturbines, Turbochargers, & Small
Turbomachines Committee, ASME IGTI (June 2013)
San Andrés, L.., Barbarie, V., Bhattacharya, A., and Gjika, K., 2012, “On the Effect of Thermal Energy Transport to the Performance of (Semi) Floating Ring Bearing Systems for Automotive Turbochargers,” ASME J. Eng. Gas Turbines Power, vol. 134 (October), 102507 [ASME paper GT2012-68074]
2012 Best Paper Award, Structures & Dynamics Committee, ASME IGTI (June 2013)
Ryu, K., and San Andrés, L., 2012, ”Effect of Cooling Flow on The Operation of a Hot Rotor-Gas Foil Bearing System,” ASME J. Eng. Gas Turbines Power, vol. 134 (October), 102511 [ASME paper GT2012-68074]
2011 BEST Rotordynamics Paper Award – 2012 IGTI Structures and Dynamics Committee
San Andrés, L., and Delgado, A., “A Novel Bulk-Flow Model for Improved Predictions of Force Coefficients in Grooved Oil Seals Operating Eccentrically,” ASME J. Eng. Gas Turbines Power, vol. 134 (May), 022509 [ASME Paper GT2011-45274].
2010 Best Paper Award for ASME Journal of Tribology (2011 IJTC Conference, LA)
Kim, T. H., and San Andrés, L., 2010, “Thermohydrodynamic Model Predictions and Performance Measurements of Bump-Type Foil Bearing for Oil-Free Turboshaft Engines in Rotorcraft Propulsion Systems,” ASME Journal of Tribology, Vol. 132(January), p. 011701
2008 BEST Rotordynamics Paper Award – IGTI Structures and Dynamics Committee
Kim, T. H., and San Andrés, L., 2009, “Effect of Side End Pressurization on the
Dynamic Performance of Gas Foil Bearings – A Model Anchored to Test Data,” ASME Journal of Engineering for Gas Turbines and Power, 131(1), pp. 012501. ( ASME Paper GT2008-50571)
Choice – Tribology & Lubrication Technology, June 2007, pp. 40-50.
De Santiago, O., and L., San Andrés, 2007, “Experimental Identification of Bearing Dynamic Force Coefficients in a Flexible Rotor – Further Developments,” Tribology Transactions, v. 50(1), p. 114-126.
2005 BEST Rotordynamics Paper Award – IGTI Structures and Dynamics Committee
Rubio, D., and L. San Andrés, 2007, “Structural Stiffness, Dry-Friction Coefficient and Equivalent Viscous Damping in a Bump-Type Foil Gas Bearing,” ASME Journal of Engineering for Gas Turbines and Power, 129, pp. 494-502. (ASME Paper GT 2005-68384)
2003 Best Rotordynamics Paper Award (IGTI, Structures & Dynamics Committee
Wilde, D.A., and San Andrés, L., 2006, “Experimental Response of Simple Gas Hybrid Bearings for Oil-Free Turbomachinery,” ASME Journal of Engineering for Gas Turbines and Power, 128, pp. 626-633. (ASME Paper No. GT 2003-38833)
XLrotor a commercial rotordynamics/bearing analysis package
rotordynamics.org, a gateway to a collection of technical literature on rotordynamics.
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PHN, Professional Hispanic Network at TAMU
Last revised: January 8, 2013
PAST PROJECTS OF EDUCATIONAL INTEREST
Research Experiences for Undergraduates: Development of
Sponsor: National Science Foundation (4 years) 2006-2010, REU#0552885
P.I: Dr. Wayne Hung (ENTC), co-pi: Dr. Luis San Andrés
Objective: The REU Summer Program funds 30 junior-level students to conduct hand-on training and research in mechanical, manufacturing, industrial, or materials engineering topics related to technological advances in microturbomachinery. This program is part of a larger scale multidisciplinary research project at TAMU to develop microturbines to enhance defense, homeland security, transportation, and aerospace applications. Activities include a series of informative seminars, field trips and social events to complement the research activities while enhancing the group cohesiveness. Students will also sharpen their communication skills through the writing of a research report and presenting their research work to industry (TRC).
Excellent facilities and services, small size research teams,
exciting interdisciplinary topics, and staying in the intellectual city of
Ten and seven qualified UGS
participated in Summer 2007 & 2008, respectively. A total of seven students
worked with Tribology Group students. Read conference paper ASME GT2009-59920. Thirteen students initiated
research in June 2009.
Download posters prepared by UG-REU students, Summer 2009
(Jose Camero, Shane Muller)
Download posters prepared by UG-REU students, Summer 2008
Rotordynamics Foil Bearings TESTS (Alex Martinez)
Rotordynamics Foil Bearings ANALYSIS (Kat Hagen)
Metal Mesh Foil Bearings (Brian Rice)
Manufacturing (Nick Niedbalski)
Download posters prepared by UG-REU students, Summer 2007
Gas Foil Bearings (Alex Martinez)
Turbochargers (Adam Wilson)
Gas Tilting Pad Bearings (H. Suh)