2. BUTE Department of Applied Mechanics1/35 Department of Applied Mechanics Head: Prof Gábor Stépán http://www.mm.bme.hu

3. BUTE Department of Applied Mechanics2/35 Contents History People Education Research areas Grants / Contracts A case study

4. BUTE Department of Applied Mechanics3/35 History Mechanics at Budapest Univ Technology & Econ 1782 Institutum Geometricum-Hydrotechnicum -1791 J Horváth -1801 J Domin -1832 Á Tomcsányi -1834 L Gröber- (Latin) -1850 Á Jedlik-1857 I Kruspér- (German) -1863 V Hauszmann-1867 M Bielek- (Hungarian) -1881 I Horváth-1913 D Nagy- (ETH Zrch) -1941 B Bresztovszky-1959 Á Muttnyánszky -1969 E Reuss-1995 G Béda

5. BUTE Department of Applied Mechanics4/35 Staff Professor2PhD students9 Assoc Professor5Prof Emeritus2 Assistant Prof2Part Assoc Prof4 Lecturer2Part Assist Prof2 Res Fellow 1Part Secretary2 Res Assistant 1Part Techn Staff1 Engineer1Part Engineer1 Total 14 21 35

6. BUTE Department of Applied Mechanics5/35 People

7. BUTE Department of Applied Mechanics6/35 People

8. BUTE Department of Applied Mechanics7/35 Courses All the subjects in Solid Mechanics to Mech Eng students both on BSc and MSc level. Basic subjects, delivered in each semester: BSc levelMechanics I (Statics) Mechanics II (Strength of Matrls) Mechanics III (Dynamics) Transition level (BSc => MSc) Applied Mechanics I (Elasticity) Applied Mechanics II (Dynamics)

9. BUTE Department of Applied Mechanics8/35 Courses MSc levelStatics Strength of Materials Kinematics and Dynamics Vibrations Elasticity and FEM Mechanics (for Power Eng) Eng Mechanics (for Ind Manag) Final exam closing all Mechanics subjects

10. BUTE Department of Applied Mechanics9/35 Courses The lectures are delivered in Hungarian, English, German, French and Russian language, too. Special MSc module in Applied Mechanics: Dynamics of MachinesContinuum Mechanics ElasticityPlasticity Nonlinear VibrationsThermomechanics Mechanics of Polymer and Composite Structures The department also presents Advanced Mechanics courses for the PhD program in Mech Eng.

11. BUTE Department of Applied Mechanics10/35 Research areas

12. BUTE Department of Applied Mechanics11/35 Publications Publication lists are available, some papers downloadable at http://www.mm.bme.hu/ In the broad field of Mechanics, several books and lecture notes were written in Hungarian. There are two books published in English: Gy. Béda, I. Kozák, J. Verhás, Continuum Mechanics, Akadémiai Kiadó, Budapest, 1995. G. Stépán, Retarded Dynamical Systems: Stability and Characteristic Functions, Longman, Harlow UK, 1989.

13. BUTE Department of Applied Mechanics12/35 International organisations IFToMM (Int Federation on Theory of Machines and Mechanisms) ICF (Int Congress on Fracture) GAMM (Gesellschaft für Angewandte Mathematik und Mechanik) SIAM (Soc Industrial and Applied Mathematics) Euromech – ENOC (European Nonlinear Oscillation Conf) and CM (Comp Mechanics) UNIDO (United Nations Industrial Development Organization)

14. BUTE Department of Applied Mechanics13/35 Editorial boards Nonlinear Science (G. Stépán) Meccanica (G. Stépán) Journal of Vibration and Control (G. Stépán) Journal of Computational and Applied Mechanics (G. Stépán) Engineering and Automation (E. Filemon) Periodica Polytechnica (A. Szekeres)

15. BUTE Department of Applied Mechanics14/35 Int seminar series – visitors (1997–)

16. BUTE Department of Applied Mechanics15/35 Computer Lab 40 computers in local network with 3 segments 4 – 4 computers in vibration & biomechanical labs 8 computers in the students' computer room (various finite element software, computer algebraic and MATLAB compatible software, also biomechanical analysis software packages) The common resources (file-service and -transfer, world wide web, COSMOS/M license) are provided by 2 Linux and 1 Windows2000 based servers

17. BUTE Department of Applied Mechanics16/35 Vibration Lab Brüel&Kjaer equipment: PULSE multi-channel dynamic msrmnt system 2 electro-dyn exciters2 signal generators, 2 amplifiers 2 digital oscilloscopes piezo accelerometersDSP cards small balancing machineshaking table 4 lab computers connected to network & devices, to PULSE system & oscilloscopes via A/D cards Strain gauge systems, industrial weight msrmnt devices, tensile test machines + workshop

18. BUTE Department of Applied Mechanics17/35 Vibration Lab

19. BUTE Department of Applied Mechanics18/35 Biomechanics Lab Arm movements, gait & spinal analysis: Zebris CMS-HS ultrasound based active markers’ system Instrumented treadmill with built in force plates Force platform for pressure distribution 24 channels EMG unit for muscle analyses Loading by the multi fitness center 4 computers with software packages: kinematical & dynamical parameters, statistical calculation.

20. BUTE Department of Applied Mechanics19/35 Biomechanics Lab

21. BUTE Department of Applied Mechanics20/35 Research grants International (1996-) PHARESeismic Assessment & Verification (Siemens, Wölfel, Westinghouse) COST P4 Nonlinear Dynamics of Machining (6 EC research groups) EU 5Rehabilitation Robotics (5 EC partners) US-HungComposite Str (Virginia SP&U) Parametric excitation (Auburn, MSU) NKFPe-Design (Scansca FEA)

22. BUTE Department of Applied Mechanics21/35 Research grants National (1999-) Mechanics of Inplantants (Univ of Medicine) Dynamic Contact Problems (Ljubljana, St.Louis) Plastic Instability Continuum Mechanics Thermo-Hygro-Mechanical Systems Dynamic Measurement System Biomechanics Measurement System

23. BUTE Department of Applied Mechanics22/35 Research projects Industrial (1996-) Nuclear Power Station (seismic verification of refueling machine, buried pipes of emergency cooling, control cables; low-cycle fatigue analyses of pipes/vessels) Hung Oil Co. (vibration/fatigue of transfer pipe) Knorr-Bremse (vibrations in electronic control of pneumatic brake systems) Westel, PannonGSM (vibration measurements) Bakony/Suzuki (noise reduction of electric mtrs) Power Stations (turbo-generator vibration prblm )

24. BUTE Department of Applied Mechanics23/35 Research story

25. BUTE Department of Applied Mechanics24/35 The answer

26. BUTE Department of Applied Mechanics25/35 Turbo-generator vibrations in the 90’s Láng-BBC 215 MW turbine + Ganz generator Vibrations just above 3000 rpm at 30% low power – critical speeds? Semi-elastic couplingJournal bearings Thermal effectsGyroscopic effects Axial forcesEngine base

27. BUTE Department of Applied Mechanics26/35 The coupling Elasticity calculations by COSMOS/M =>

28. BUTE Department of Applied Mechanics27/35 The bearings Reynolds’ equation (BVP) Non-isotropic elasticity (also non-conservative)

29. BUTE Department of Applied Mechanics28/35 Thermal effects Modulus of elasticity variation with temperature Gyroscopic effects are important above 3000 rpm

30. BUTE Department of Applied Mechanics29/35 Campbell diagram – critical speeds No critical speed problem But: bearing 5 over-sized base torsional mode

31. BUTE Department of Applied Mechanics30/35 Turbine blade polishing – force control NEI Parsons Newcastle (UK)

32. BUTE Department of Applied Mechanics31/35 Stability problems at force control Vibrations at the base (also for milling of blades)

33. BUTE Department of Applied Mechanics32/35 Force control instability in RehaRob

34. BUTE Department of Applied Mechanics33/35 Stability of high-speed milling Stability chart and vibration frequencies

35. BUTE Department of Applied Mechanics34/35 Stability of up-milling and down-milling

36. BUTE Department of Applied Mechanics35/35 Thank you for your attention.