# Acoustic Applications in Mechanical Engineering: Structure-Borne Sound versus Air-Borne Sound

Save this PDF as:

Size: px
Start display at page:

## Transcription

1 Acoustic Applications in Mechanical Engineering: Structure-Borne Sound versus Air-Borne Sound Marold Moosrainer CADFEM GmbH 2009 July 6th

2 Agenda Introduction into acoustics: common phrases, basic equation Solving structural vibration problems with ANSYS Solving structure-borne sound problems with ANSYS SBSOUND Solving air-borne sound problems with ANSYS (FEM) Solving air-borne sound problems with WAON (BEM) -1-

3 Introduction machine acoustics speed of sound, wavelength, frequency basic concept of solving acoustic problems by simulation -2-

4 Some phrases of machine acoustics machine fluid, e.g. air transient flow direct noise generation: flow acoustics (CFD + acou.) oscillating forces machine structure indirect noise generation: vibroacoustics (FEM + acou.) building structure structure-borne sound: a sound wave propagating in a solid medium air-borne sound: a sound wave propagating in air -3-

5 Speed of sound wavelength frequency Note that we solve the acoustic wave equation to model reflection, scattering, absorption and thus we have to resolve each wave in its spatial pattern important equation: c = λ f air: c 340m/s, f=1000hz λ=0.34m water: c 1500m/s, f=1000hz λ=1.5m rule of thumb FEM, BEM: linear elements per wavelength required elements for a domain of characteristic size a: FEM (volume mesh): ~O(N 3 ) BEM (surface mesh): ~O(N 2 ) large acoustic FEM problem: 10M DOFs large acoustic BEM problem: 20k DOFs large acoustic FMBEM problem: 200k DOFs -4-

6 Basic concept of solving acoustic problems by simulation Signal analysis (MBS, test, FFT) Structure-borne sound analysis (FEM) Air-borne sound analysis (FEM, BEM) Psycho acoustics (e.g. DIN 45631) use N 5 percentile values for transient noise -5-

7 Solving Structural Vibration Problems with ANSYS modal analysis harmonic response analysis ANSYS application example: train wheel -6-

8 Solving structural vibration problems with ANSYS modal analysis: standard procedure for the dynamic assessment of a structure compute the potential vibration shapes & resonance frequencies of a structure without considering any excitation a library of specific solvers for special tasks: standard: block Lanczos (LANB), large problems: PCG Lanczos (LANPCG) large problems, up to modes (SNODE) rotordynamics: incl. gyroscopic effects (QRDAMP) damped structures: incl. damping matrix (QRDAMP, DAMP) break-squeal analysis: incl. friction (QRDAMP,UNSYM) FSI coupled systems: incl. fluid (UNSYM) however: no amplitude results -7-

9 Modal analysis: mode shapes of a train wheel

10 Solving structural vibration problems with ANSYS harmonic response analysis now we introduce an excitation, for instance a point force F=1N specified over a frequency range Hz only distinct modes will contribute to the structural response, e.g. the modes having a nodal line at the excitation point will not be excited use mode superposition instead of inverting full matrices whenever possible because of efficiency usually the response amplitude at some points is postprocessedversus frequency -9-

11 Frequency response UY(f) at contact point -10 -

12 Solving Structure-Borne Sound Problems with ANSYS SBSOUND basic equation of machinery acoustics ANSYS application example: train wheel -11-

13 Computation of structure-borne sound Acoustics is driven by velocity v=iωu not by structural displacement u. Acoustics assumes an ideal non-viscous fluid without shear layers. Thus only the surface normal component of the structural vibration velocity is important. Acoustics is not a local phenomenon like fatigue where we have to deal with local notch stresses. Acoustics is a global phenomenon where the whole structure may contribute to sound radiation. thus let s try to get one integral quantity to describe the acoustic fingerprint of a structure by simply averaging the normal surface velocities For all this ideas apply the basic equation of machinery acoustics (cf. textbooks) ~ f ) 2 n P( = ρ cσ ( f ) A< v~ ( f ) > -12 -

14 ANSYS macro library SBSOUND (structure-borne sound) Perform normal projection of the displacement results Compute surface averaged mean square velocity by integration Do all computations in modal subspace for higher efficiency and extended postprocessing capabilities (modal contribution plot, panel contribution plot) modal contributions show the influence of distinct modes

15 Alternatively: bar chart of modal contributions for fixed f total result (red bar) together with the (blue) modal contributions the same figure is available for panel contributions if panels are defined before calling SBSOUND -14 -

16 Sound radiation is not only a function of velocity amplitude! Sound pressure p for two plates vibrating in the same spatial pattern, both with equal velocity amplitude v 0 but with different frequencies. There is, however, a big difference in the sound radiation! Radiation efficiency s! at 50 Hz and at 200 Hz note the equal pressure scale -15 -

17 Solving Air-Borne Sound Problems with ANSYS (FEM) interior frequency domain acoustic FEM: living room exterior acoustics time domain FEM: offshore hammer -16 -

18 Interior acoustics: modal analysis by ANSYS FEM living room with defined absorbent linings: mode 2 at 28 Hz (right) mode 50 at 152 Hz (left) -17 -

19 Exterior acoustics: transient analysis by ANSYS FEM Offshore hammer: for offshore applications a steel pipe has to be fixed in shallow sea water. The pile has a length of 30m above sea ground, a radius of 2m, and a wall thickness of 50mm; half-sin force FY 1E8N. It s partially immersed in water (water height 25m), where the speed of sound c=1500m/s, and fluid density ρ=1000kg/m 3, apply absorbent boundary condition at exterior surfaces pipe exterior fluid interior fluid -18 -

20 Results: animated displacement u and sound pressure p Structural result pipe displacement radial component important Acoustic result sound pressure animation sound pressure signals at different microphone positions P -19 -

21 Solving Air-Borne Sound Problems with WAON (BEM) features of BEM and FMBEM FMBEM workflow for train wheel example ANSYS Workbench WAON interface -20 -

22 Computation of air-borne sound (typical BEM workflow) 1. structural FE model 2. modal model (FEM): eigenfrequencies, mode shapes, modal damping 3. Harmonic frequency (FEM) response results (structureborne sound): surface displacements 4. Acoustic BEM solves wave equation, no fluid volume mesh required. a) BEM result: sound pressure p, sound power P, radiation efficiency σ b) field point mesh result (half sphere): sound pressure p, intensity I -21 -

23 Compare FEM & BEM before talking about the new development FMBEM let s have a more general view on BEM BEM FEM BEM: divide only the surface. easy to create a mesh. The sound radiation problem can be handled completely no need for any particular boundary condition like in FEM for exterior acoustic problems Interior Exterior Interior Exterior -22 -

24 Acoustics Software: & WAON specialized acoustic software for efficient frequency domain sol. technology based on Fast Multipole BoundayElement Method (FMBEM), a state of the art numerical technology pro s easy to learn (2-4 hours or even a seminar by WEBEX is sufficient) easy to apply even if acoustics isn t your every day business easy mesh operations surface mesh of your radiating structure is sufficient low memory requirements, high performance, high frequencies (comp. to BEM): e.g. automotive sensor applications at ultrasonic frequencies very efficient (park distance control, alarm) -23 -

25 What is FMBEM Fast Multipole algorithm is applied to the boundary element method (BEM) The world's first commercial acoustic-analysis program with using FMBEM Accuracy is the same as conventional BEM Conventional BEM FMBEM Calculation of interaction between all elements Memory requirement O(N 2 ) Solution time O(N 3 ) : direct solver O(N 2 ) : iterative solver Calculation of interaction between cells instead of between elements (maths: clustering&multipoleexpansion) Solution time O(N ~ N logn) Memory requirement O(N ~ N logn) -24 -

26 Engine: Conventional BEM vs. FMBEM Available on larger structures and higher frequency at shorter times! Radiated noise from engine Pressure or output power distribution around scooter engine. 4.5 khz analysis by 84,000 DOF mesh. Required memory(4.5khz) Conventional BEM : 113 GB FMBEM by WAON : 3 GB -25 -

27 Compare FEM & BEM FEM acoustics large amount of data particularly for large distance results or scatter objects volume meshes: prep/post efforts developer: easy math, user: more effort to handle non-reflecting boundary conditions like FLUID130, perfectly matching layer (PML) for radiation problems strong in both frequency & time domain modal analysis available non-homogeneous acoustic media porous media (foam) available (Biot theory) nonlinearities available (large amplitudes) convectedwave eq. for flow eff. available BEM acoustics reduced amount of data even for large distance results surface meshes: easy prep/post, less data developer: complex math, user: more easy to handle radiation problem solved very naturally because every boundary element knows about the radiation cond. analytically only strong in frequency domain no modal analysis available acoustic medium has to be homogeneous volomedamping idealized by complex c confined to linear theory quiescent acoustic medium -26 -

28 ANSYS/WAON workflow: air-borne sound train wheel example reloaded Prepare WAON BEM (surface) mesh in ANSYS and export it to CDB formats prepare WAON field point mesh (virtual microphones) in ANSYS and export it to CDB format -27 -

29 Import BEM mesh & map ANSYS structural vibration results WAON feature tree (max. 7 dialogues to work through intuitively) -28 -

30 Import field point mesh (virtual microphones) & perform FMBEM harmonic response analysis (2-3 min.) -29 -

31 Postprocess pressure amplitude & pressure level in db & intensity vectors on field point mesh -30 -

32 Compare air-borne power to structure-borne sound power blue curve: input power (structure-borne sound power identical to SBSOUND result) due to radiation efficiency σ this always is a very conservative estimate of the radiated active output power in red (air-borne sound power) good agreement at higher frequencies above coincidence where we have radiation efficiency σ=

33 Even more Easy to Use: Interface WBtoWAON Developed by CYBERNET SYSTEMS WBtoWAON Developed by CYBERNET SYSTEMS WAON ANSYS Workbench Developed by ANSYS, Inc

34 WAON: some more solved acoustic applications Sound Pressure Level[dB] Point1 Point2 Point Frequency[kHz] -33 -

35 Multiphysics: FEM/FEM/BEM application example Investigation of the Noise Behavior of an Electric Motor electromagnetics struct. vibrations Structure: Single phase alternating current electric motor acoustics Task: Simulate noise behavior for silent operation Method: Coupled electro-mechanic, structural-dynamic and acoustic analysis Schallleistungspegel [db] f [Hz] -34 -

36 Conclusion ANSYS FEM for structural vibration analysis, multiphysics analysis (e.g. electro-magnetic excitation) SBSOUND (ANSYS macro library provided by CADFEM) for a quick rough structure-borne sound assessment WAON for really doing fully-fledged acoustic simulations FMBEM is a very comfortable technique particularly for the new user because there is no need for volume meshing like in acoustic FEM FMBEM technique overcomes the traditional drawback of conventional BEM: matrix storage requirements & large CPU time due to direct solvers. High-speed iterative solvers available. FMBEM by WAON allows the analysis of large scale models & high frequencies acoustics is easy acoustics is fun! -35 -

### Acoustics Analysis of Speaker

Acoustics Analysis of Speaker 1 Introduction ANSYS 14.0 offers many enhancements in the area of acoustics. In this presentation, an example speaker analysis will be shown to highlight some of the acoustics

### CONSTRUCTION MACHINERY CAB VIBRO-ACOUSTIC ANALYSIS AND OPTIMISATION

CONSTRUCTION MACHINERY CAB VIBRO-ACOUSTIC ANALYSIS AND OPTIMISATION L.Bregant 1, G.Miccoli 2, M.Seppi 1 1 University of Trieste, Dept. of Mechanical Engineering, Trieste, Italy 2 IMAMOTER Institute, National

### Finite Element Analysis for Acoustic Behavior of a Refrigeration Compressor

Finite Element Analysis for Acoustic Behavior of a Refrigeration Compressor Swapan Kumar Nandi Tata Consultancy Services GEDC, 185 LR, Chennai 600086, India Abstract When structures in contact with a fluid

### Fluid structure interaction of a vibrating circular plate in a bounded fluid volume: simulation and experiment

Fluid Structure Interaction VI 3 Fluid structure interaction of a vibrating circular plate in a bounded fluid volume: simulation and experiment J. Hengstler & J. Dual Department of Mechanical and Process

### Dispersion diagrams of a water-loaded cylindrical shell obtained from the structural and acoustic responses of the sensor array along the shell

Dispersion diagrams of a water-loaded cylindrical shell obtained from the structural and acoustic responses of the sensor array along the shell B.K. Jung ; J. Ryue ; C.S. Hong 3 ; W.B. Jeong ; K.K. Shin

### A new generalized approach to Statistical Energy Analysis (SEA)

A new generalized approach to Statistical Energy Analysis (SEA) Phil SHORTER 1, Vincent COTONI 1, Julien LEGAULT 1, Robin LANGLEY 2, Stephane CARO 1 1 wave six LLC. 2 University of Cambridge, United Kingdom

### Overview. also give you an idea of ANSYS capabilities. In this chapter, we will define Finite Element Analysis and. Topics covered: B.

2. FEA and ANSYS FEA and ANSYS Overview In this chapter, we will define Finite Element Analysis and also give you an idea of ANSYS capabilities. Topics covered: A. What is FEA? B. About ANSYS FEA and ANSYS

### Design of Cellular Composite for Vibration and Noise Control: Effects of Inclusions and Filling Patterns on Acoustic Bandgap

Design of Cellular Composite for Vibration and Noise Control: Effects of Inclusions and Filling Patterns on Acoustic Bandgap Vijay Kumar and D. Roy Mahapatra Department of Aerospace Engineering Indian

### FLUID STRUCTURE INTERACTION TO PREDICT LINER VIBRATIONS IN AN INDUSTRIAL COMBUSTION SYSTEM

FLUID STRUCTURE INTERACTION TO PREDICT LINER VIBRATIONS IN AN INDUSTRIAL COMBUSTION SYSTEM Rob A. Huls, Jaap F. van Kampen, Jim B.W. Kok and André de Boer University of Twente P.O. Box 217, 75 AE Enschede,

### Fluid-Structure Acoustic Analysis with Bidirectional Coupling and Sound Transmission

VPE Swiss Workshop Acoustic Simulation 12. Sept. 2013 Fluid-Structure Acoustic Analysis with Bidirectional Coupling and Sound Transmission Reinhard Helfrich INTES GmbH, Stuttgart info@intes.de www.intes.de

### Aeroacoustic Analogy for the Computation of Aeroacoustic Fields in Partially Closed Domains

INSTITUT FÜR MECHANIK UND MECHATRONIK Messtechnik und Aktorik Aeroacoustic Analogy for the Computation of Aeroacoustic Fields in Partially Closed Domains A. Hüppe 1, M. Kaltenbacher 1, A. Reppenhagen 2,

### Acoustic analysis of an induction motor with viscoelastic bearing supports. Abstract. 1. Introduction

The 2002 International Congress and Exposition on Noise Control Engineering Dearborn, MI, USA. August 19-21, 2002 Acoustic analysis of an induction motor with viscoelastic bearing supports H.G. Tillema

### Titelmasterformat durch Klicken bearbeiten

Titelmasterformat durch Klicken bearbeiten ANSYS AIM Product simulation for every engineer Erke Wang CADFEM GmbH Georg Scheuerer ANSYS Germany GmbH Christof Gebhardt CADFEM GmbH All products involve multiple

### Structural and Thermal Analysis of Brake Drum

Middle-East Journal of Scientific Research 0 (8): 101-1016, 014 ISSN 1990-933 IDOSI Publications, 014 DOI: 10.589/idosi.mejsr.014.0.08.11404 Structural and Thermal Analysis of Brake Drum Anup Kumar and

### CHAPTER 4 4 NUMERICAL ANALYSIS

41 CHAPTER 4 4 NUMERICAL ANALYSIS Simulation is a powerful tool that engineers use to predict the result of a phenomenon or to simulate the working situation in which a part or machine will perform in

### 3-D WAVEGUIDE MODELING AND SIMULATION USING SBFEM

3-D WAVEGUIDE MODELING AND SIMULATION USING SBFEM Fabian Krome, Hauke Gravenkamp BAM Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin, Germany email: Fabian.Krome@BAM.de

### Chapter 15 Wave Motion. Copyright 2009 Pearson Education, Inc.

Chapter 15 Wave Motion Characteristics of Wave Motion Types of Waves: Transverse and Longitudinal Energy Transported by Waves Mathematical Representation of a Traveling Wave The Wave Equation Units of

### High Performance Computing: A Review of Parallel Computing with ANSYS solutions. Efficient and Smart Solutions for Large Models

High Performance Computing: A Review of Parallel Computing with ANSYS solutions Efficient and Smart Solutions for Large Models 1 Use ANSYS HPC solutions to perform efficient design variations of large

### Waves. Wave: A traveling disturbance consisting of coordinated vibrations that transmit energy with no net movement of the matter.

Waves Wave: A traveling disturbance consisting of coordinated vibrations that transmit energy with no net movement of the matter. Source: some kind of disturbance from the state of equilibrium. Propagation:

### CAD and Finite Element Analysis

CAD and Finite Element Analysis Most ME CAD applications require a FEA in one or more areas: Stress Analysis Thermal Analysis Structural Dynamics Computational Fluid Dynamics (CFD) Electromagnetics Analysis...

### The Sonometer The Resonant String and Timbre Change after plucking

The Sonometer The Resonant String and Timbre Change after plucking EQUIPMENT Pasco sonometers (pick up 5 from teaching lab) and 5 kits to go with them BK Precision function generators and Tenma oscilloscopes

### physics 111N oscillations & waves

physics 111N oscillations & waves periodic motion! often a physical system will repeat the same motion over and over! we call this periodic motion, or an oscillation the time it takes for the motion to

### 7.1 Echo sounders. Principle of proximity sensor 1. PZT 2. matching layer 3. metal ring 4. radiation. Trade mark of Siemens A.G.

7 COMBINED APPLICATIONS The designs described in this section. use PZT transducers both as a transmitter and a receiver, clearly demonstrating the reversible nature of the piezoelectric effect. Typical

### EFFECTS OF TRIM AND TRIM MODELING ON IN-CAB NOISE

The 21 st International Congress on Sound and Vibration 13-17 July, 2014, Beijing/China EFFECTS OF TRIM AND TRIM MODELING ON IN-CAB NOISE Chavan Achyut, Raut Manoj and R Ramkumar. College of Engineering

### Advancements in Laser Doppler Vibrometry for Ultrasonic Applications. Ultrasonics Industry Symposium Eric Lawrence, Polytec Inc.

Advancements in Laser Doppler Vibrometry for Ultrasonic Applications Ultrasonics Industry Symposium Eric Lawrence, Polytec Inc. Contents Introduction to Laser Vibrometry New PSV-500 Scanning Vibrometer

### Piezoelectric Simulations

Piezoelectric Simulations Outline Overview Examples Relevant Products Useful Features Overview Industries Using Piezoelectric Devices Aerospace Oil & Gas Automotive Piezoelectric Devices MEMS Acoustics

### Lab 14: Standing Waves

Lab 14: Standing Waves Objectives: To understand superposition of waves To understand how a standing wave is created To understand relationships between physical parameters such as tension and length of

### Laboratory facilities for sound transmission measurements validation by measurement and simulation methods

Laboratory facilities for sound transmission measurements validation by measurement and simulation methods Marlon MEISSNITZER 1 ; Blasius BUCHEGGER 2 ; Heinz FERK 3 1, 2, 3 Graz University of Technology,

### Best practices for efficient HPC performance with large models

Best practices for efficient HPC performance with large models Dr. Hößl Bernhard, CADFEM (Austria) GmbH PRACE Autumn School 2013 - Industry Oriented HPC Simulations, September 21-27, University of Ljubljana,

### Sound Insulation of Walls with a new Mortar-Mix System

Sound Insulation of Walls with a new Mortar-Mix System Martin Schneider, Heinz-Martin Fischer Stuttgart University of Applied Sciences, Germany. Summary A new clay block walling system developed by the

### OpenFOAM Optimization Tools

OpenFOAM Optimization Tools Henrik Rusche and Aleks Jemcov h.rusche@wikki-gmbh.de and a.jemcov@wikki.co.uk Wikki, Germany and United Kingdom OpenFOAM Optimization Tools p. 1 Agenda Objective Review optimisation

### The simulation of machine tools can be divided into two stages. In the first stage the mechanical behavior of a machine tool is simulated with FEM

1 The simulation of machine tools can be divided into two stages. In the first stage the mechanical behavior of a machine tool is simulated with FEM tools. The approach to this simulation is different

### MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

Exam Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A transverse wave is propagated in a string stretched along the x-axis. The equation

### A. Ricci, E. Giuri. Materials and Microsystems Laboratory

Presented at the COMSOL Conference 2009 Milan FSI Analysis of Microcantilevers Vibrating in Fluid Environment Materials and Microsystems Laboratory Politecnico di Torino Outline Brief Presentation of Materials

### Vibration reduction of thermal break balcony connections

Vibration reduction of thermal break balcony connections M. Schneider and H.-M. Fischer University of Applied Sciences, Schellingstr. 24, 70174 Stuttgart, Germany martin.schneider@hft-stuttgart.de 5405

### 11 Vibration Analysis

11 Vibration Analysis 11.1 Introduction A spring and a mass interact with one another to form a system that resonates at their characteristic natural frequency. If energy is applied to a spring mass system,

### Realistic Simulation of a Flexible Mechanism using ANSYS Solutions. Achuth Rao, Ph.D. Product Line Manager Product Management Group ANSYS Inc.

Realistic Simulation of a Flexible Mechanism using ANSYS Solutions Achuth Rao, Ph.D. Product Line Manager Product Management Group ANSYS Inc. Solution Brands and Products Structural Fluids Explicit ANSYS/Mechanical

### Drive market-winning innovation, without risk

SOLIDWORKS SIMULATION Drive market-winning innovation, without risk Ensure adequate exit duct sizing with Flow simulation Check resonance between the fan and the motor Truck Mount SnowBlower Wausau Everest

### Sound Waves. PHYS102 Previous Exam Problems CHAPTER. Sound waves Interference of sound waves Intensity & level Resonance in tubes Doppler effect

PHYS102 Previous Exam Problems CHAPTER 17 Sound Waves Sound waves Interference of sound waves Intensity & level Resonance in tubes Doppler effect If the speed of sound in air is not given in the problem,

### Aeroelastic Investigation of the Sandia 100m Blade Using Computational Fluid Dynamics

Aeroelastic Investigation of the Sandia 100m Blade Using Computational Fluid Dynamics David Corson Altair Engineering, Inc. Todd Griffith Sandia National Laboratories Tom Ashwill (Retired) Sandia National

### MEMS Multiphysics Simulation in ANSYS Workbench David Harrar II, PhD Ozen Engineering, Inc.

MEMS Multiphysics Simulation in ANSYS Workbench David Harrar II, PhD Ozen Engineering, Inc. 1 Ozen Engineering, Inc. We are the local ANSYS Channel Partner With over 25 years of experience in FEA and CFD

### Commercial CFD Software Modelling

Commercial CFD Software Modelling Dr. Nor Azwadi bin Che Sidik Faculty of Mechanical Engineering Universiti Teknologi Malaysia INSPIRING CREATIVE AND INNOVATIVE MINDS 1 CFD Modeling CFD modeling can be

### Guidelines to engine dynamics and vibration

The Ship Power Supplier Guidelines to engine dynamics and vibration by Hannu Tienhaara Technology Wärtsilä Corporation In recent years shipyards and shipowners have increasingly tuned in to the negative

### Vincent Constantin, CADFEM (Suisse) AG

Fast Titelmasterformat and reliable Bolt durch Assessment Klicken bearbeiten inside ANSYS Vincent Constantin, CADFEM (Suisse) AG Agenda Introduction VDI 2230 Bolt Assessment inside ANSYS Verification Examples

### DYNAMICAL ANALYSIS OF SILO SURFACE CLEANING ROBOT USING FINITE ELEMENT METHOD

International Journal of Mechanical Engineering and Technology (IJMET) Volume 7, Issue 1, Jan-Feb 2016, pp. 190-202, Article ID: IJMET_07_01_020 Available online at http://www.iaeme.com/ijmet/issues.asp?jtype=ijmet&vtype=7&itype=1

### VIBRATION DUE TO ROTATION UNBALANCE

Fall 08 Prepared by: Keivan Anbarani Abstract In this experiment four eccentric masses are used in conjunction with four springs and one damper to simulate the vibration. Masses are aligned in different

### High Performance Computing for Mechanical Simulations using ANSYS. Jeff Beisheim ANSYS, Inc

High Performance Computing for Mechanical Simulations using ANSYS Jeff Beisheim ANSYS, Inc HPC Defined High Performance Computing (HPC) at ANSYS: An ongoing effort designed to remove computing limitations

### ME6130 An introduction to CFD 1-1

ME6130 An introduction to CFD 1-1 What is CFD? Computational fluid dynamics (CFD) is the science of predicting fluid flow, heat and mass transfer, chemical reactions, and related phenomena by solving numerically

### Sound Absorption and Sound Absorbers

Sound Absorption and Sound Absorbers Slides to accompany lectures in ME 610: Engineering 00 by A. F. Seybert Department of Mechanical Engineering Lexington, KY 40506-0108 Tel: 859-57-6336 x 80645 Fax:

### An Introduction to Piezoelectric Transducer Crystals. Piezoelectric Materials and their Properties

An Introduction to Piezoelectric Transducer Crystals Piezoelectric Materials and their Properties Certain single crystal materials exhibit the following phenomenon: when the crystal is mechanically strained,

### Frequency domain application of the Hot-Spot method for the fatigue assessment of the weld seams

Frequency domain application of the Hot-Spot method for the fatigue assessment of the weld seams Dr. Ing. Sauro Vannicola 1 sauro.vannicola@ch.abb.com Dr. Ing. Luigi De Mercato 2 luigi.de-mercato@ch.abb.com

### Chapter 18 4/14/11. Superposition Principle. Superposition and Interference. Superposition Example. Superposition and Standing Waves

Superposition Principle Chapter 18 Superposition and Standing Waves If two or more traveling waves are moving through a medium, the resultant value of the wave function at any point is the algebraic sum

### Dynamic Measurement of Brake Pads Material Parameter

VDA Dynamic Measurement of Brake Pads Material Parameter 315 This non-binding recommendation by the German Association of the Automotive Industry (VDA) has the following objectives: This standard treats

### Simulation im Bereich der Windenergie ein Überblick. Dipl.-Ing. (FH) Nathalie Mattwich, CADFEM GmbH Dipl.-Phys. oec Stephan Hecht, ANSYS Germany GmbH

Simulation im Bereich der Windenergie ein Überblick Dipl.-Ing. (FH) Nathalie Mattwich, CADFEM GmbH Dipl.-Phys. oec Stephan Hecht, ANSYS Germany GmbH Agenda Uhrzeit Thema Referent 16:00 16:30 Simulation

### Ultrasonic Testing (UT) [9]

Ultrasonic Testing (UT) [9] Ultrasonic Testing (UT): A nondestructive test method that uses high frequency sound energy to conduct examinations and make measurements. Sound: The mechanical vibration of

### Porous Materials for Sound Absorption and Transmission Control

Purdue e-pubs Publications of the Ray W. School of Mechanical Engineering 8-1-2005 Porous Materials for Sound Absorption and Transmission Control J Stuart Bolton, bolton@purdue.edu Follow this and additional

### MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

Exam Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A 660-Hz tone has an intensity level of 54 db. The velocity of sound in air is 345 m/s.

### Chapter 21 Mechanical Waves. A PowerPoint Presentation by Paul E. Tippens, Professor of Physics Southern Polytechnic State University

Chapter 21 Mechanical Waves A PowerPoint Presentation by Paul E. Tippens, Professor of Physics Southern Polytechnic State University 2007 Objectives: After completion of this module, you should be able

### Building Design for Advanced Technology Instruments Sensitive to Acoustical Noise

Building Design for Advanced Technology Instruments Sensitive to Acoustic Noise Michael Gendreau Colin Gordon & Associates Presentation Outline! High technology research and manufacturing instruments respond

### 3D PIPELINE ANALYSIS SOFTWARE. Bringing added value to pipeline engineers worldwide. Editor Module

Bringing added value to pipeline engineers worldwide SAGE Profile 3D has been specifically designed to assist pipeline engineers in the design, installation and analysis of offshore pipelines. The powerful

### Co-simulation of Microwave Networks. Sanghoon Shin, Ph.D. RS Microwave

Co-simulation of Microwave Networks Sanghoon Shin, Ph.D. RS Microwave Outline Brief review of EM solvers 2D and 3D EM simulators Technical Tips for EM solvers Co-simulated Examples of RF filters and Diplexer

### Ray Optics Minicourse COMSOL Tokyo Conference 2014

Ray Optics Minicourse COMSOL Tokyo Conference 2014 What is the Ray Optics Module? Add-on to COMSOL Multiphysics Can be combined with any other COMSOL Multiphysics Module Includes one physics interface,

### ANSYS Tutorial. Modal Analysis

ANSYS Tutorial Slides to accompany lectures in Vibro-Acoustic Desin in Mechanical Systems 2012 by D. W. Herrin Department of Mechanical Enineerin Lexinton, KY 40506-0503 Tel: 859-218-0609 dherrin@enr.uky.edu

### DYNAMIC ANALYSIS ON STEEL FIBRE

International Journal of Civil Engineering and Technology (IJCIET) Volume 7, Issue 2, March-April 2016, pp. 179 184, Article ID: IJCIET_07_02_015 Available online at http://www.iaeme.com/ijciet/issues.asp?jtype=ijciet&vtype=7&itype=2

### Rock Bolt Condition Monitoring Using Ultrasonic Guided Waves

Rock Bolt Condition Monitoring Using Ultrasonic Guided Waves Bennie Buys Department of Mechanical and Aeronautical Engineering University of Pretoria Introduction Rock Bolts and their associated problems

### SCATTERED SOUND POWER FROM A RIGID STRUCTURE USING NON-NEGATIVE INTENSITY

SCATTERED SOUND POWER FROM A RIGID STRUCTURE USING NON-NEGATIVE INTENSITY Daipei Liu, Herwig Peters, Nicole Kessissoglou School of Mechanical and Manufacturing Engineering, UNSW Australia, Sydney, NSW

### ACCELERATING COMMERCIAL LINEAR DYNAMIC AND NONLINEAR IMPLICIT FEA SOFTWARE THROUGH HIGH- PERFORMANCE COMPUTING

ACCELERATING COMMERCIAL LINEAR DYNAMIC AND Vladimir Belsky Director of Solver Development* Luis Crivelli Director of Solver Development* Matt Dunbar Chief Architect* Mikhail Belyi Development Group Manager*

### Piezoelectric Polymer Speakers Application Note Aug 98 Rev A

1 Aug 98 Rev A INTRODUCTION A loudspeaker is a transducer which transforms electrical signals into acoustic sound. Conventional speakers usually consist of a vibrating surface (called a diaphragm) and

### Vibration Isolation in Data Centers

Vibration Isolation in Data Centers Vibrations in Data Centers Vibrations in Data Centers can be produced by nearby construction works, heavy traffic, railways or even the own cooling units inside or next

### Back to Elements - Tetrahedra vs. Hexahedra

Back to Elements - Tetrahedra vs. Hexahedra Erke Wang, Thomas Nelson, Rainer Rauch CAD-FEM GmbH, Munich, Germany Abstract This paper presents some analytical results and some test results for different

### Steve Elliott Institute of Sound and Vibration Research (ISVR) University of Southampton

Active Noise Control: Physical Principles and Practical Applications Steve Elliott Institute of Sound and Vibration Research (ISVR) University of Southampton Institute of Sound and Vibration Research University

### CHAPTER 3 MODAL ANALYSIS OF A PRINTED CIRCUIT BOARD

45 CHAPTER 3 MODAL ANALYSIS OF A PRINTED CIRCUIT BOARD 3.1 INTRODUCTION This chapter describes the methodology for performing the modal analysis of a printed circuit board used in a hand held electronic

### TWO-DIMENSIONAL FINITE ELEMENT ANALYSIS OF FORCED CONVECTION FLOW AND HEAT TRANSFER IN A LAMINAR CHANNEL FLOW

TWO-DIMENSIONAL FINITE ELEMENT ANALYSIS OF FORCED CONVECTION FLOW AND HEAT TRANSFER IN A LAMINAR CHANNEL FLOW Rajesh Khatri 1, 1 M.Tech Scholar, Department of Mechanical Engineering, S.A.T.I., vidisha

### Development and optimization of a hybrid passive/active liner for flow duct applications

Development and optimization of a hybrid passive/active liner for flow duct applications 1 INTRODUCTION Design of an acoustic liner effective throughout the entire frequency range inherent in aeronautic

### Introduction to acoustic imaging

Introduction to acoustic imaging Contents 1 Propagation of acoustic waves 3 1.1 Wave types.......................................... 3 1.2 Mathematical formulation.................................. 4 1.3

### SEISMIC ANALYSIS OF A VERTICAL WATER TANK

SISOM 20 and Session of the Commission of Acoustics, Bucharest 25-26 May SEISMIC ANALYSIS OF A VERTICAL WATER TANK Nicolae ZEMTEV * AMEC NUCLEAR RO e-mail: nicolae.zemtev@amecnuclear.ro The calculation

### Offshore Wind Turbine Support Structures

1 Wind Power R&D Seminar Deep Sea Offshore Wind Royal Garden Hotel, Trondheim, Norway January 21, 2011 Effect of Foundation Modeling Methodology on the Dynamic Response of Offshore Wind Turbine Support

### FLUX / GOT-It Finite Element Analysis of electromagnetic devices Maccon GmbH

FLUX / GOT-It Finite Element Analysis of electromagnetic devices Maccon GmbH Entwurfswerkzeuge für elektrische Maschinen MACCON GmbH 09/04/2013 1 Flux software Modeling electromagnetic and thermal phenomena

Advanced Loads Webinar Patrick Cunningham January 2013 CAE Associates Inc. and ANSYS Inc. Proprietary 2013 CAE Associates Inc. and ANSYS Inc. All rights reserved. E-Learning Webinar Series This presentation

### Waves and Sound Part 1

Waves and Sound Part 1 Intro Write the following questions on a blank piece of paper (don t answer yet) 1. What is the difference between a mechanical and electromagnetic wave? 2. What is the difference

### MAKE SURE TA & TI STAMPS EVERY PAGE BEFORE YOU START

Laboratory Section: Last Revised on September 21, 2016 Partners Names: Grade: EXPERIMENT 11 Velocity of Waves 0. Pre-Laboratory Work [2 pts] 1.) What is the longest wavelength at which a sound wave will

### Kalibrierung von Materialparametern und Optimierung eines Elektromotors mit optislang

Kalibrierung von Materialparametern und Optimierung eines Elektromotors mit optislang ----------------------------------------------------------------- Calibration of material parameters and optimization

### Sound Level Sensor DATA HARVEST. Product No Range: 40 to 110 dba Resolution: 0.1 dba Response time: 125 ms

Sound Level Sensor Product No. 3175 Range: 40 to 110 dba Resolution: 0.1 dba Response time: 125 ms Range: ±2000 mv Resolution: 1 mv Frequency response: 100 Hz - 7 khz DATA HARVEST Data Harvest Group Ltd

### This chapter describes how you can model solidification and melting in FLUENT. Information is organized into the following sections:

Chapter 21. Melting Modeling Solidification and This chapter describes how you can model solidification and melting in FLUENT. Information is organized into the following sections: Section 21.1: Overview

### 19 th INTERNATIONAL CONGRESS ON ACOUSTICS MADRID, 2-7 SEPTEMBER 2007 THE SOUND FIELD IN AN EAR CANAL OCCLUDED BY A HEARING AID

19 th INTERNATIONAL CONGRESS ON ACOUSTICS MADRID, 2-7 SEPTEMBER 27 THE SOUND FIELD IN AN EAR CANAL OCCLUDED BY A HEARING AID PACS: 43.66.Ts, 43.64.Ha, 43.38.Kb, 43.2.Mv Stinson, Michael R.; Daigle, Gilles

### Waves I: Generalities, Superposition & Standing Waves

Chapter 5 Waves I: Generalities, Superposition & Standing Waves 5.1 The Important Stuff 5.1.1 Wave Motion Wave motion occurs when the mass elements of a medium such as a taut string or the surface of a

### Electro-Seismic Survey System

Electro-Seismic Survey System M. du Preez ABSTRACT: The electro-seismic survey can be used with great success in geophysical surveys where the aim is to site groundwater. The presence of water in the porous

### TwinMesh Grid Generator and CFD Simulation with ANSYS CFX

TwinMesh Grid Generator and CFD Simulation with ANSYS CFX 2nd Short Course on CFD in Rotary Positive Displacement Machines London, 5th 6th September 2015 Dr. Andreas Spille-Kohoff Jan Hesse Rainer Andres

### Lab Exercise 7: Doppler Radar

Lab Exercise 7: Doppler Radar Contents 7-1 PRE-LAB ASSIGNMENT.................. 22 7-2 INTRODUCTION...................... 22 7-2.1 Speed Discrimination................ 23 7-2.2 Doppler Antenna..................

### Angle of an incident (arriving) ray or particle to a surface; measured from a line perpendicular to the surface (the normal) Angle of incidence

The maximum displacement of particles of the medium from their mean positions during the propagation of a wave Angle of an incident (arriving) ray or particle to a surface; measured from a line perpendicular

### CFD SIMULATION OF SDHW STORAGE TANK WITH AND WITHOUT HEATER

International Journal of Advancements in Research & Technology, Volume 1, Issue2, July-2012 1 CFD SIMULATION OF SDHW STORAGE TANK WITH AND WITHOUT HEATER ABSTRACT (1) Mr. Mainak Bhaumik M.E. (Thermal Engg.)

### Aeroacoustic simulation based on linearized Euler equations and stochastic sound source modelling

Aeroacoustic simulation based on linearized Euler equations and stochastic sound source modelling H. Dechipre a, M. Hartmann a, J. W Delfs b and R. Ewert b a Volkswagen AG, Brieffach 1777, 38436 Wolfsburg,

### Part IV. Conclusions

Part IV Conclusions 189 Chapter 9 Conclusions and Future Work CFD studies of premixed laminar and turbulent combustion dynamics have been conducted. These studies were aimed at explaining physical phenomena

### STUDY OF DAM-RESERVOIR DYNAMIC INTERACTION USING VIBRATION TESTS ON A PHYSICAL MODEL

STUDY OF DAM-RESERVOIR DYNAMIC INTERACTION USING VIBRATION TESTS ON A PHYSICAL MODEL Paulo Mendes, Instituto Superior de Engenharia de Lisboa, Portugal Sérgio Oliveira, Laboratório Nacional de Engenharia

### Standing wave modes of a violin.

Introduction. Standing wave modes of a violin. The intent of this lab is to explore a few modes of a complicated object, and employ some of the tools used in physics labs to measure their properties and

### Waves Introduction A wave is a disturbance in a medium that caries energy without a net movement of particles.

Waves Introduction A wave is a disturbance in a medium that caries energy without a net movement of particles. A wave: transfers energy. usually involves a periodic, repetitive movement. does not result

### 08/19/09 PHYSICS 223 Exam-2 NAME Please write down your name also on the back side of this exam

08/19/09 PHYSICS 3 Exam- NAME Please write down your name also on the back side of this exam 1. A sinusoidal wave of frequency 500 Hz has a speed of 350 m/s. 1A. How far apart (in units of cm) are two

### RF-thermal-structural-RF coupled analysis on the travelling wave disk-loaded accelerating structure

RF-thermal-structural-RF coupled analysis on the travelling wave disk-loaded accelerating structure PEI Shi-Lun( 裴 士 伦 ) 1) CHI Yun-Long( 池 云 龙 ) ZHANG Jing-Ru( 张 敬 如 ) HOU Mi( 侯 汨 ) LI Xiao-Ping( 李 小