Department of Applied Mechanics

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

2. Contents • History • People • Education • Research areas • Grants / Contracts • A case study BUTE Department of Applied Mechanics

3. 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 BUTE Department of Applied Mechanics

4. Staff Professor 2 PhD students 9 Assoc Professor 5 Prof Emeritus 2 Assistant Prof2 Part Assoc Prof 4 Lecturer2 Part Assist Prof 2 Res Fellow1 Part Secretary 2 Res Assistant1 Part Techn Staff 1 Engineer 1 Part Engineer 1 Total 14 21 35 BUTE Department of Applied Mechanics

5. People BUTE Department of Applied Mechanics

6. People BUTE Department of Applied Mechanics

7. 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) BUTE Department of Applied Mechanics

8. Courses MSc level Statics 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 BUTE Department of Applied Mechanics

9. Courses The lectures are delivered in Hungarian, English, German, French and Russian language, too. Special MSc module in Applied Mechanics: Dynamics of Machines Continuum Mechanics Elasticity Plasticity Nonlinear Vibrations Thermomechanics Mechanics of Polymer and Composite Structures The department also presents Advanced Mechanics courses for the PhD program in Mech Eng. BUTE Department of Applied Mechanics

10. Research areas BUTE Department of Applied Mechanics

11. Publications Publication lists are available, some papers downloadableathttp://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. BUTE Department of Applied Mechanics

12. 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) BUTE Department of Applied Mechanics

13. 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) BUTE Department of Applied Mechanics

14. Int seminar series – visitors (1997–) BUTE Department of Applied Mechanics

15. 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 BUTE Department of Applied Mechanics

16. Vibration Lab Brüel&Kjaer equipment: PULSE multi-channel dynamic msrmnt system 2 electro-dyn exciters 2 signal generators, 2 amplifiers 2 digital oscilloscopes piezo accelerometers DSP cards small balancing machine shaking 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 BUTE Department of Applied Mechanics

17. Vibration Lab BUTE Department of Applied Mechanics

18. 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 distribution24 channels EMG unit for muscle analysesLoading by the multi fitness center 4 computers with software packages: kinematical & dynamical parameters, statistical calculation. BUTE Department of Applied Mechanics

19. Biomechanics Lab BUTE Department of Applied Mechanics

20. Research grants International (1996-) PHARE Seismic Assessment & Verification (Siemens, Wölfel, Westinghouse) COST P4 Nonlinear Dynamics of Machining (6 EC research groups) EU 5 Rehabilitation Robotics (5 EC partners) US-Hung Composite Str (Virginia SP&U) Parametric excitation (Auburn, MSU) NKFP e-Design (Scansca FEA) BUTE Department of Applied Mechanics

21. 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 BUTE Department of Applied Mechanics

22. 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) BUTE Department of Applied Mechanics

23. Research story BUTE Department of Applied Mechanics

24. The answer BUTE Department of Applied Mechanics

25. 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 coupling Journal bearings Thermal effects Gyroscopic effects Axial forces Engine base BUTE Department of Applied Mechanics

26. The coupling Elasticity calculations by COSMOS/M => BUTE Department of Applied Mechanics

27. The bearings Reynolds’ equation (BVP) Non-isotropic elasticity (also non-conservative) BUTE Department of Applied Mechanics

28. Thermal effects Modulus of elasticity variation with temperature Gyroscopic effects are important above 3000 rpm BUTE Department of Applied Mechanics

29. Campbell diagram – critical speeds No critical speed problem But: bearing 5 over-sized base torsional mode BUTE Department of Applied Mechanics

30. Turbine blade polishing – force control NEI Parsons Newcastle (UK) BUTE Department of Applied Mechanics

31. Stability problems at force control Vibrationsat the base(also formilling ofblades) BUTE Department of Applied Mechanics

32. Force control instability in RehaRob BUTE Department of Applied Mechanics

33. Stability of high-speed milling Stability chart and vibrationfrequencies BUTE Department of Applied Mechanics

34. Stability of up-milling and down-milling BUTE Department of Applied Mechanics

35. Thank you for your attention. BUTE Department of Applied Mechanics