Practical Aspects of Technical Acoustics

1) Fundamentals of engineering acoustics
Sound, noise levels, non-physical aspects
Noise impact for aeronautics
Structure borne sound

2) Fundamentals of elasticity and vibration
Damping of structure borne sound
Impedance

3) Sound waves
Propagation of sound waves in fluids
Reflection, refraction, diffraction, Doppler effect
Waves in ducts
Absorption
Meteorological aspects

4) Measurement and rating of sound
Actuation and sensing: impedance hammer, microphone, accelerometer, strain sensor, laser
Laser vibration meter
Signal processing
Free field; reverberation room
Intensity measurement
Experimental modal analysis
Sound level ratings

5) Sound proofing measures
Absorption, isolation, damping
Transmission loss

6) Active noise and vibration control
piezo actuators, active vibration absorbers, control design, application: propeller noise reduction

7) Simulation methods

8) Aerospace applications

After the successful participation in this course, the students will be able to explain how to develop a simulation model with regard to various acoustic questions. They are able to differentiate between existing measurement methods and to evaluate the results of simulation models. Students can also analyze noise reduction techniques and apply them to a practical problem. They understand the different technical measures for vibration reduction and can develop solutions for simple, acoustical problems in aviation.

Basics of mechanics

By means of presentations, the students are taught the physical, mathematical and methodical principles of technical acoustics and the basic approaches for the development of a model based on acoustic problems. The students strengthen their knowledge in supervised exercises, in which the theoretical contents are applied to practical examples. The results are then extensively discussed and analyzed. The students will be given an insight into the acoustical measurement technology in the form of an excursion to the acoustics labs of Airbus in Ottobrunn.

Laptop+Beamer, Blackboard

Cremer, L., Heckl, M. Körperschall, 1996, ISBN-13: 978-3540546313

Crighton, D.G., Dowling, A.P., Ffowcs-Williams, J.E., Heckl, M., Leppington, F.G., Modern methods in analytical acoustics. Acoustical Society of America, 1995

Michael Möser , Technische Akustik, 6. Auflage von 2005, 370 Seiten, 180 Abb., Paperback; Springer-Verlag GmbH & Co. KG | ISBN: 3540225102

M. Möser, Engineering Acoustics - An introduction to noise control; Springer Verlag, 2nd edition 2009, ISBN: 978-3540927228

F. Fahy, Foundations of engineering acoustics; Elsevier, ISBN: 9780122476655, 2000
Kuttruff, H.: Akustik - Eine Einführung. S. Hirzel, 2004, ISBN 3-7776-12448

Smith, B.,J., Peters, R.,J., Owen, S.; Acoustics and noise control; Addison Wesley Longman Limited; ISBN 0-582-08804-6; 1996

Lerch, R., Sessler, G., Wolf, W.; Technische Akustik; Springer Verlag, 2009, ISBN 978-3-540-23430-2

Rossing, T. D., Dunn, F., Hartmann, W.M., Campbell, D.M., Fletcher, N.H.; Handbook of Acoustics; Springer Verlag, 2007, ISBN 978-0-387-30446-5

In the 60-minute written exam, the comprehension of the basics of technical acoustics and acoustic measurement techniques are carried out by means of solving practical exercises and theoretical problems. The exam is written at the end of the lecture period and repetition is only possible in the next summer semester.
On the basis of a current question from the aviation industry with the aim of noise control, the learned methods and measures shall be applied by the students in order to demonstrate that they understood the complexity of the transition of the physical-technical problem to a model solution and simulation in practical engineering work.