PROFESSORES VISITANTES NO PPGEM EM 2015.

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1 PROFESSORES VISITANTES NO PPGEM EM PROF DR. BIN TANG Lecturer da Dalian University of Technology, China no programa Ciência Sem Fronteira para o período de 01/03/2013 a 28/02/2016 projeto coordenado pelo Prof Michael J. Brennan PROF DR. SANG-MYEONG KIM High Safety Vehicle Core Technology Research Center, Inje University, Coréia do Sul, deverá ficar por um período de um ano no DEM, projeto coordenado pelo Prof Michael J. Brennan.

2 CHALES R FARRAR E ERIC BRIAN FLYNN - Los Alamos National Laboratory, NM USA MICHAEL TODD da Universidade da California San Diego USA Estes 3 professores ofereceram em janeiro de 2015 a disciplina condensada: STRUCTURAL HEALTH MONITORING USING STATISTICAL PATTERN RECOGNITION

3 PROF. DR. PHIL JOSEPH University of Southampton - UK Noise and Vibration Control This course will be given by Professor Mike Brennan from UNESP and Professor Phil Joseph from the University of Southampton in the UK. The aim of the course is to give an overview of noise and vibration control techniques. It will cover the fundamentals of acoustics, vibration and signal processing before proceeding to specific aspects of noise and vibration control. It will be of general interest to all those who wish to work/are working in the area of vibration and noise control. Lectures will be given each morning and students will then work on Exercises in the afternoon. To gain credit for the course students will have to complete the exercises on completion of the course and submit the work electronically. As a wide-range of topics will be studied at a relatively advanced level, students should have a general background in the area mechanical engineering and be proficient in the use of Matlab as this will be used in several of the exercises. Próximas Visitas Novembro/2015 PROF. NICOLÒ BACHSCHMID

4 Irá ministrar dois cursos Curso 1 Diagnostics of rotating machinery (structural health monitoring) Diagnostics require the identification of characteristic symptoms from vibration measurements. Sensors signal analysis and monitoring systems are described. Different cases of malfunctions in industrial rotating machinery are presented, and the symptoms are described It will be shown how malfunctions can be modelled, and the corresponding symptoms simulated. Qualitative diagnostics is effected by creating probabilistic links between symptoms and malfunctions, creating e.g. the matrix symptom-malfunction, which allows by means of fuzzy logic to estimate the ranking of probabilities. Quantitative diagnostics allows to identify not only the malfunction but also its position along the shaft of the machine, and its severity. It will be shown, as an example that not only the presence of a transverse crack in a rotating shaft can be identified, but also its position and its depth.

5 Curso 2 Vibrations of blades and blade rows in turbomachinery Vibrational behavior of periodic (rotating) structures is recalled. Effects of mistuning are introduced, as well as the effect of intermittent contacts between the blades. A continuous contact with friction has great influence on the vibrational behavior. Normal contact force can be optimized to have minimum vibration amplitude. Blade stresses and fatigue are calculated by steam turbine manufacturers assuming standard engine order excitation in resonance for small blades. Long blades are instead tuned in the design stage to avoid resonances with engine order excitation. In off design conditions instabilities can occur for long blades of the last stage of condenser steam turbines. Measurements obtained with tip timing equipment show instability and forced motion due to engine order excitation. Damping of blade row is identified as well as excitation amplitude.

6 In partial arc admission conditions the control stage highly loaded. It will be shown how the excitation and the response can be modelled.