Engineer in Acoustics, Noise and Vibration, Structural ...users.skynet.be/thomas.peuvrel/download/Thomas_Peuvrel_competen… · Acoustics, Noise and Vibration, Structural Dynamics,

Page 1 of 19

Competence File – Thomas Peuvrel

Engineer in

Acoustics, Noise and Vibration,

Structural Dynamics,

Audio and DSP

10 Years Experience


Page 2 of 19

COMPETENCIES

Management

• Analysing client’s needs.

• Negotiation with clients and suppliers.

• Project Management: Functional and Technical assistance.

• Team Management: technical resources planning, review meetings and following-up,

coaching, supervising.

Domain of activities

Engineering Acoustics

• Noise level measurements: sound power, pressure and intensity levels, Sound Exposure

Level, Environmental noise statistical parameters (Leq, L10, L90) with A/B/C weightings and

common noise indicators Lden, Lnight according to EU 2002/49/EC directive.

• Room acoustics: Impulse responses, T60, EDT, Echo, Speech Transmission Index, RASTI and

absorption computation and measurements

• Numerical acoustics: Finite Elements, Boundary Elements, Infinite Boundary Elements

Methods (modelling and post-processing). Case analysis and calculation handling with

commercial software.

• Management and execution of sound/noise testing: Transducers recommendation, execution

and analysis of tests in air cavities or open field (including transfer functions measurements,

acoustical modal analysis)

• Acoustical testing during flights on civil aircraft: particular equipment recommendation and

troubleshooting (conditioners, microphones) and recorders specifications, validation and

analysis, correlation work with aircraft parameters.

• Analytical acoustics: wave propagation theory, sound levels, sound in ducts and enclosures,

multipoles sources. Calculation sheets for noise insulation and criteria index, sound power

radiation, acoustics screening, silencer design.

• Active and Passive control of sound and vibration: active system and transducers

specification, convergence algorithm implementation.

• Passive performance assessment: Transmission Loss Factor for N&V performance assessment

(floating slabs, soil, floor, partitions, windows, HVAC silencer)

• Environmental acoustics: environmental noise measurements and predictions (noise mapping)

• Aero-Acoustics: Flow induced noise calculation based on the aero-acoustical analogy theory.


Page 3 of 19

Engineering Vibration

• Vibration levels measurements: acceleration, velocity, displacement of environmental or

ground-borne vibration.

• Vibration transfer functions measurements for dedicated analysis or structural modal analysis

• Ground-borne vibration measurements according to the following standards: DIN

4150-2 Human exposure to vibration and buildings and DIN 4150-3 Effects of vibration on

structures. Knowledge of BS 6841, BS 6472, ISO 2631 standards.

• Transducers recommendation and best-fit.

• Transfer Path measurement: soil transmissibility

• Complementary measurements: force and constraints measurements.

Instrumentation

• Free-field microphones, sound intensity probe, volume velocity acoustical source, white noise

source, shaker, mini-shaker, impact and roving-hammers, mono-axial & tri-axial

accelerometers, seismic and high frequency accelerometers, force cells and strain gage

sensors.

NVH (Noise Vibration and Harshness) and Structural Dynamics

• Virtual prototyping: Finite Element modelling and post-processing for noise and vibration

behaviour of structures (car: body-in-white, engine, trims, components; aircraft parts) and

coupled vibro-acoustics systems (car interiors). Use of several CAE techniques: Sub-

structuring, modal reduction technique and wave-based methods. Achievement of modal

analysis, FRF calculations, panel contributions and prediction of noise and vibration levels.

Modelling and calculation works with commercial software.

• Analytical structural dynamics: wave propagation in plates, beam and shells.

• Management and execution of structural modal analysis: measurements of transfer functions

for structural modal analysis (with shaker, mini-shaker or roving hammer excitations).

Performance of tests and validation works.

• Management and execution of noise and vibration measurements: vibro-acoustics transfer

functions measurements, engines order tracking.

• Vibration testing during flights on civil aircraft: particular equipment recommendation and

troubleshooting (conditioners, accelerometers) and recorders specifications, validation and

analysis, correlation work with aircraft parameters.

• Correlation analysis between and uses of updating techniques: Comparison between results

obtained from computation and from tests; manual or automatic updating tasks of FE models

using dedicated solvers in order to obtain accurate models for reference. Product design

refinement.


Page 4 of 19

Digital Signal Processing and Software Implementation

• Applied signal processing: signal conditioning (DFT, FFT, Windowing, Power Spectrum Density,

H1&H2 estimators, auto-power and cross-power functions, correlation and coherence

functions)

• Non-stationary and non-linear methods in signal processing: time-frequency representation

• Control/Adaptive filtering Systems: signal processing techniques for Acoustics Echo

Cancellers, Stationary and Non-stationary Noise Suppression algorithms using adaptive filters

(Steepest descent, LMS algorithms) and/or non-adaptive FIR, IIR filters design.

• Audio system design: signal processing for auralisation techniques (3D sound) using IIR and

FIR filters design, control algorithm (convergence, LMS algorithm).

• C code programming of signal processing algorithms for further porting tasks on DSP platforms (embedded systems).

• Numerical algebra implementation in FORTRAN, domain decomposition techniques and MPI technology for parallel computation.

Other fields of competencies

• Optics, Electromagnetism, Electronics (R,C,L,OA circuits), Thermodynamics, Organic and

Physical Chemistry

Computing and Technical Skills

Mathematical Development and Systems Simulation

• Mathematical Development and Digital Signal Processing using MATLAB® Software

• Mathematical Simulation and Systems Modelling using SIMULINK® (Standard Simulink® and

Signal Processing blockset libraries)

• Realisation of Graphical User Interface and standalone models using Matlab/Simulink® Real-

Time workshop. Real-Time Workshop is used for building a Windows-based stand-alone

generic real-time version of Simulink model using generated C code and the Microsoft Visual

C/C++ compiler.


Page 5 of 19

Measurements Systems

• Environmental Noise and Vibration level measurements multichannel system:

SINUS Messtechnik GmbH SOUNDBOOK

• Frontend multichannel data acquisition:

LMS Scadas II & III: PDT, QDAC, PQFA, PQCA, PQMA modules.

• Sound Level Meters: B&K and 01dB

CAE Analysis Techniques

• Finite Element Modelling: PATRAN, ANSYS, Animator (GUI).

• Finite Element Structural Computational Analysis: NASTRAN, LMS Virtual.Lab NVH.

• FEM, BEM, IBEM Acoustical Computational Analysis (post-processing and prediction):

LMS SYSNOISE, LMS Virtual.Lab Acoustics.

• Acoustics and Vibration measurement: LMS Cada-X (TMon, FMon), LMS Test.Lab

Desktop/Online Random and Acoustic Reduction/Throughput Acquisition/Signature Acquisition.

• Modal Analysis measurement and post-processing: LMS Cada-X (Modal Analysis),

LMS Test.Lab Modal Analysis

• Time and signature measurements: LMS Cada-X (TMon, SMon, Running Modes),

LMS Test.Lab Order Tracking.

• Correlation between Finite Element calculation and measurements: LMS Gateway and

NASTRAN SOL200

Audio Measurements Techniques and

• Acoustical measurement system for rooms acoustics and speakers impedance and radiation

characteristics: MLSSA (DRA Laboratories).

• Electrical Transfer Function Measurements, Total Harmonic Distortion (THD): Audio Precision.

Audio and GSM Telecommunications Test Systems

• Head Acoustics® Telecommunication testing Systems: ACQUA Software, MFE VI front-end,

HATS artificial/dummy head, ear/mouth simulator, Noise and EQ systems.

• GSM Network Simulator: Rhode &Schwarz®CMU200 Universal Radio Communication Tester

Environmental - Community noise prediction

• Environmental Noise prediction and Noise Mapping Software: IMMI


Page 6 of 19

Technologies

• Known Programming Languages: C, FORTRAN, Pascal

• Mathematical development: MATLAB, SIMULINK

• Programming environment: MS Visual Studio,

• O.S: Windows , Mac OS X and UNIX (SUN, HP, IBM workstations) environment

• Interix, Exceed emulators

Various

• Computed Aided Design: Autodesk AutoCAD Architecture

• Adobe Audition, Acrobat, Photoshop, FTP explorer

Language Skills

• French: Native Language

• English: Fluent

• Dutch: Basic Knowledge

• Spanish: Basic Knowledge

• German: Notions


Page 7 of 19

EXPERIENCE

Noise and vibration engineering for urban light rail transport Infrastructures and rolling stock (Tramways & Metro)

STIB-MIVB, Brussels, Belgium

June 2009 – Now

Expert Engineer in Noise and Vibration and Rail/Wheel Interaction

Introduce company

The largest Belgian urban public transport company, the Société des Transports Intercommunaux de Bruxelles (STIB), serves the 19 cities of the Brussels Capital Region as well as 11 other outlying cities. It covers a surface area of 241.5 km² and provides transport for a population of over 1,100,000 inhabitants and thousands of commuters. The STIB network has 4 metro lines, 19 tram lines, 50 bus lines. Over 311,6 million people chose public transport to get around the capital. Over the past 10 years, the number of STIB customers increased by almost 80%. (http://www.stib.be/)

Intervention

Context Within the Infrastructures department of public transport company STIB-MIVB, Responsible for Infrastructure Noise and Vibration control for urban light rail transport: Metro and Tramways. Design of network extension and plan/implement infrastructure noise and vibration control system (track bedding, encapsulation, sub-ballast mats, floating slabs). Collaborate with a team of experts (STIB and Bombardier Transportation) in rail/wheel interaction focusing particularly on controlling rail deterioration (corrugation and wear) and therefore induced vibration

Objectives • Carrying out investigations into public complaints due to urban light rail operation (metro and trams) and also verify infrastructure mitigation performance related to ground-borne vibration (track bedding, rail encapsulation, floating slabs, sub-ballast mats).

• Impact surveys: prediction of noise, vibration and ground-borne noise levels in case of network extension or track replacement.

• Control at source: reducing noise and vibration induced by track wear and corrugation (that is increasing due to load on wheels and bogie axle of recent low floor trams) and rolling stock component.

• Work jointly with Environmental Public Local Authority for the investigation of environmental acoustics and vibration in Brussels. Plan and execute measurements campaign for community noise/vibration issues. Discuss/Lobby related new policies.


Page 8 of 19

Actions • I conduct vibration measurement according to the following German standard DIN 4150-2 (Human exposure to vibration in buildings) and DIN 4150-3 (Effects of vibration on structures). Although using different signal integration and weightings, criteria and level thresholds, the DIN 4150-2 standard has the same purpose (i.e. assessment of human exposure to vibration) as standards BS 6841 & BS 6472 or ISO 2631-1 & ISO 2631-2. These measurements are used to carry out investigations into public complaints due to urban light rail operation (metro and trams) but also construction works. This aims also to verify infrastructure mitigation performance related to ground-borne vibration (track bedding, rail encapsulation, floating slabs, sub-ballast mats).

• Besides conventional vibration measurements, complementary measurements are achieved in case of network extension or track replacement: transfer path measurement from existing or future tracks and residential dwellings’ foundations (i.e. soil transmissibility) and Load spectrums applied on rails from different rolling stocks. They intend to predict the levels of vibration and ground-borne noise and therefore decide the need of mitigating measures so as to comply with the regulation.

• As far as community noise is concerned, I conduct specific airborne noise measurements of rolling stocks and railways referring to methodology set in a convention agreed with local authorities. This also requires the use of IMMI noise mapping software (subcontracted). If the specific noise levels do not meet the required criteria, simulation (based on speed, train frequency, screening) is achieved and insulation measures taken

• Investigation of N&V emission and constraints effect on rail of rolling stock component (wheel, bogies, primary suspension stiffness and braking system effects), railways structures (track, sleepers, slabs, ballast, concrete layers), railway systems (turnouts, crossing) and operational rules (signalisation, speed).

• Since the major source of rolling noise and vibration is due to wheel-rail contact, understanding the interaction is of utter most importance to control emission at source. I participate in the monitoring of rail corrugation within the Brussels Metro and Trams network. Surface corrugation on the head of rail track is mostly overcome by grinding. However I investigate lateral track wear corrugation that is increasing due to load on wheels and bogie axle of recent low floor trams. To overcome this issue; I coordinate tests of different solution for friction change (Top of rail lubrication, sticks, automatic greasing of wheel flanges based on a GPS system and tags). This is expected to reduce squealing noise as well in tight curvatures which I monitor.

• I also inspect turnouts (switches) and crossings that could be damaged by worn wheels. “False flange” may develop on the field side of wheels that have experienced severe tread wear and cause noise and vibration when impacting the crossing. I participate in a scheme defining wheel reprofilling. I investigate the possibility to include N&V criteria to safety and comfort criteria for reprofilling wheels. Wheel flats and out-of-round wheels are also of concern.

• Finally I have a role in designing/controlling according to the specifications switch blades, rolling stock wheel profiles, wheel-rail contacts and infrastructures track lines/beds.


Page 9 of 19

Results Comply with the environmental noise and vibration regulation.

Decide the need of mitigating measures for rail network extension/replacement.

Prevent the lateral track wear corrugation issue by friction change of wheel/rail contact.

Operational recommendation for N&V attenuation and definition of maintenance policy of wheel re-profiling (avoid wheel flats, out-of-round wheels and false flange).

Recommendation for construction work noise and vibration new policy among the company.


Page 10 of 19

Acoustic Systems and Audio Algorithm development

Philips CE, iLab Sound & Acoustics Group, Philips Technology Campus, Leuven, Belgium

April 2007 – Mai 2009

Acoustics / Audio DSP Engineer

Introduce company

Within Philips Consumer Electronics the CE Innovation Lab (iLab) is responsible for defining future products. iLab’s Sound and Acoustics department is the main competence center within Philips CE for electro-acoustics and sound processing. The application area’s are as diverse as home theater systems, portable audio and video players, wireless audio centers, traditional and noise cancelling headphones, audio systems for flat screen televisions, webcams and multimedia speakers. (http://www.philips.com/)

Intervention

Context Development of innovative audio concepts for home, mobile, automotive and medical applications. These concepts always include a Digital Signal Processing component, in some cases, linked with a unique acoustical arrangement of transducers.

Objectives Development of audio systems, realization and management of project deliverables within the budget and timing constraint. The activities cover all phases of the concept creation process.

Actions • Identify customer needs and/or propose new concepts. Execute technical feasibility studies and define a project planning accordingly.

• Create new innovative audio concepts using Matlab/Simulink for prototyping (e.g. sound enhancement algorithms, loudness, Parametric EQ with clipping control). Audio processing and system performances analysis.

• Promote the audio concepts by developing standalone demonstrators (writing executables files using Matlab/Simulink real time workshop).

• Benchmark the concept with competing solutions.

• Write algorithm in C code and optimize it to gain performance efficiency and to be as close as possible to the porting stage on different DSP platforms.

• Write technical specifications and support the product development by close collaboration with engineers in other disciplines such as electrical and mechanical development, DSP software development, product testing.

• Define required acoustical properties of transducers (loudspeaker drivers, microphones) and their acoustic enclosures if the audio concept requires it, using the laboratory measurement methods and tools.

Results Innovative audio concepts development and screening of technological trends. Code optimization to fulfill customers’ DSP platforms requirements. Contribute to the growth of the group’s competence, by sharing knowledge and experience with colleagues and program management.

Technical Environment

Digital Signal Processing for audio development, C programming, porting on DSP chips.


Page 11 of 19

Acoustic Echo Cancellation and Noise Suppression Algorithms Integration and Tuning Support

NXP Software (former Philips Software), Philips Technology Campus, Leuven – Belgium

March 2005-March 2007

Audio DSP Engineer

Introduce company

NXP Software is an Independent Software Vendor (ISV). It specializes in innovative multimedia solutions to help mobile device and consumer electronics manufacturers deliver Acoustic Echo Cancellation and Noise Suppression solutions. NXP Software has established strong partnerships with key vendors to ensure optimum flexibility, ease-of-integration and interoperability between hardware and software platforms. Its LifeVibes™ software is used in over 250 million mobile devices, making the company one of the market leader in software solutions for mobile multimedia. (http://www.software.nxp.com/)

Intervention

Context Acoustic Echo Canceller and Noise Suppression software solutions that address the entire audio chain (from the near-end to far-end side) helps handset and Bluetooth accessories makers to create phones that ensure quality voice communications on every call, under any conditions. These algorithms need to be correctly implemented and ported on customers’ DSP platforms. In addition, the algorithm control parameters need to be tuned according to the acoustical characteristics of the Device Under Test (e.g. Mobile phone, Car-kit, Bluetooth Headset) to provide the best performance. Critical echoes may occur when the mechanical/acoustical coupling is stronger between the loudspeaker and the microphone.

Objectives • Supports the correct implementation, integration in customers’ DSP platforms.

• Fine-tuning of the specific voice coding algorithm in customers’ devices (acoustic echo cancellation).

• Tuning of noise suppression, speech intelligibility enhancement and compressor algorithms.

• Assessment of acoustical design performance and system improvement in strong echo path situation in the device

Actions • Execute audio and telecommunications tests with dedicated system (Head Acoustics ACQUA) using a GSM network simulator (R&S CMU200) to troubleshoot software integration and algorithm performance in Devices Under Tests.

• Develop methodologies for parameters’ tuning in different modes (Handset, Hand-free, wired Headset and Bluetooth Headset). On-field testing with customers (using commercial GSM/UMTS network provider). Provide trainings to customers on algorithm specifications and tuning methodologies.

• Advise customers on the speakers and microphones specifications and insulation on the PCB to reduce strong coupling (acoustic echo path) in critical devices and user modes.

Results Customers satisfaction in technical troubleshooting and tuning of AEC algorithms and in audio quality improvement. Effective reaction to escalated issues on devices before mass production. Gained didactic experience by giving training. Contribution to the development of state–of-the-art AEC and noise suppression algorithm in Bluetooth systems.


Page 12 of 19

Noise and Vibration Flight Testing on AIRBUS A320 and A340 aircraft

Airbus France, Noise & Vibration Flight Testing – EYTXGA division, Toulouse, France, October 2004-January 2005

Analyst Engineer

Introduce company

The Acoustic & Vibration Testing EYTXGA division at Airbus France deals with acoustic and vibration testing (including modal analysis) of equipments and structures of aircraft (wings, engines, nacelles, cabins, cockpits) as well as acoustic and vibration troubleshooting, certification and flight testing. EYTXGA works jointly with Airbus Acoustics and Environment EEA division. (www.airbus.com)

Intervention

Context Aircraft equipments, structures, or enclosures like cabins or cockpits, need vibratory and acoustical assessments. Tests need to be executed during flights as structures can be highly excited during all flight phases and therefore cause dysfunctions, breaks, hydraulic leaks and/or high vibration levels. High noise levels can also occur during flights and cause annoyance and/or safety concerns for the crew and passengers. Environmental issues of aircraft exterior noise are also assessed especially at take-off, approach and landing phases.

Objectives Realisation of noise and vibration tests on A320 and A340 aircraft. Two major projects were achieved:

• Levels measurement of aerodynamics noise generation in so-called ‘burst-disk cavities’ located at the bottom part of wings and investigation of its tonal noise characteristics. Assessment of several vortex generator’s noise attenuation performance placed in front of cavities.

• Vibration levels on T-fittings devices of hydraulic network in wings. Determination of possible causes of leaks and condition of occurrence.

Actions • Answer Flight Test Requests from EEA division (bureau of study)

• Prepare and advise test specifications (transducers, dynamic and frequency ranges, gain channels, type of recorders) to A320 and A340 aircraft test teams (responsible for flight equipment installation and measurement line).

• Follow-up of flight tests by attending meetings with pilots, flight engineers and flight test managers.

• Acquire data recorded on SIR/DAT tape, transfer on workstation and perform post-processing of data for tests validation on short notice after flights.

• Determine acoustical and/or vibration levels over flight duration and during particular phases and compute frequency spectra. In-depth analysis of data.

• Correlation work with aircrafts parameters (engine power, hydraulic pressure system, wings’ flap/slat configurations, altitude, airspeed flight phases, etc..)

• Establish reports and contribute to elaboration of solutions with EEA.

Results An efficient control and processing of recorded data with fast preliminary results delivery. Achievement of accurate report on noise and vibration phenomena and on coherence with flight events. Improve noise and vibration attenuation performance on Airbus civil aircraft in partnership with the design office.


Page 13 of 19

Experimental and numerical study of acoustic and vibro-acoustic responses of a real scale rigid walled model of a car cavity and its attached door

LMS International, Engineering Services, Leuven, Belgium, March–September 2004

Project Engineer

Introduce company

LMS provides solutions for functional performance: testing systems, multidisciplinary virtual prototyping software, engineering services and collaborative engineering tools that enable product refinement and process efficiency. LMS is partner of companies in the automotive, aerospace, and other manufacturing industries in the world. (http://www.lmsintl.com/)

Intervention

Context Within the framework of “TRICARMO” project (Trimmed Car Acoustic Response Modelling), the dedicated tasks investigate the contribution of a MAZDA car door to the interior acoustics of a rigid walled model of the car cavity. This investigation focuses particularly on the effect of the door trim on car interior acoustics as well as on engineering guidelines for joint modelling needs.

Objectives • Execute numerical and experimental analysis to assess the vibro-acoustic and acoustics behaviour of the whole system.

• Settle a step by step procedure enabling FE model refinement and updating.

• Localise and estimate the modelling effort in order to obtain accurate prediction of vibro-acoustical behaviour of a car door and its components and of the acoustics of the car interior.

Actions 1. Design of individual and adapted experimental set-ups.

2. Follow the dedicated step by step procedure by executing successive experimental and numerical modal analysis in free-free conditions of: panel structures of the door and window separately; then all door parts assembled (including mirror, window lifter, handle and trim).

3. Updating tasks (manual or automatic) on the FE model with emphasis on stiffness of material, mass of elements, design and modelling consideration of connector, attachment of the auxiliaries and weather-strips. Updates made accordingly with correlation conclusions obtained by comparing experimentally and numerically data at each step.

4. Execute successive experimental and numerical modal analysis of the door constrained (i.e. casted in concrete frame): panel structures and window and then with mirror, window lifter, handle and trim.

5. Apply same methodology as described at point 3 with point 4 results.

6. Numerical simulation of complete system’s vibro-acoustics behaviour and car interior acoustics rendering from optimized updated models.

Results In-detailed study of the vibro-acoustic effects of inserting a complete car door onto the acoustic behaviour of the cavity. Achievement of an important step towards a complete trimmed body model, since the door with all its closures, weather-strips and trim components can be considered as a very good, yet limited and controllable example of the structural complexity of real-life applications. Reach finite element modelling guidelines.


Page 14 of 19

Implementation of an iterative solver in SYSNOISE software for interior acoustics

LMS International, CAE Division, Noise and Vibration Group, Leuven, Belgium, November 2003–February 2004

Research Engineer - Programmer

Introduce company

LMS provides solutions for functional performance: testing systems, multidisciplinary virtual prototyping software, engineering services and collaborative engineering tools that enable product refinement and process efficiency. LMS is partner of companies in the automotive, aerospace, and other manufacturing industries in the world. (http://www.lmsintl.com/)

Intervention

Context A majority of noise and vibration problems in automotive and aeronautical manufactured products occur in the range between the low and high frequency, the so-called mid-frequency range. The conventional deterministic method (Finite Elements Analysis) can lead to poor results as it has its frequency limitation. The development of parallel computation appears as a successful alternative for deterministic methods to overcome mid-frequencies issues.

Objectives • Design, implement and validate a global iterative solver dedicated to interior acoustics in SYSNOISE software that enables parallel computation and therefore reduces computational effort and costs in order to tackle mid-frequency modelling issues.

Actions • Develop a domain decomposition approach in the software environment that enables parallel computation; i.e. separate a coupled vibro-acoustic problem into two distinctive domains, i.e. a structural and an acoustic problem, which can be solved in separate solution schemes that could be distributed over different processors.

• Program in FORTRAN language an iterative algorithm in software source code (updates iteratively the Right Hand Sides (RHS) of the two sub-domain problems that are solved directly by each processor thereafter).

• Validate the development.

• Adapt the algorithm to solve issues and to enable feasibility.

• Develop of a new theoretical iterative solver approach.

• Validate the new scheme analytically with MATLAB.

• Publish the results.

Results • Development and assessment of the feasibility of a new challenging approach in vibro-acoustics numerical computation.

• Identification of alternative approaches overcoming the problem (compensate for uncontrolled divergences).

• The research led to the publication of a proceeding article and was presented at the Institute of Acoustics Spring Conference at the University of Southampton in March 2004. The paper is accessible at this address: (http://users.skynet.be/thomas.peuvrel/download/Paper_IoA_2004.pdf)


Parallel computation, MPI (Message Passing Interface) technology, FETI (Finite Element Tearing Interface) technology.


Page 15 of 19

VIPROM project: Extending deterministic methods to higher frequency

LMS International, CAE Division, Noise and Vibration Group, Leuven, Belgium,

April 2002–October 2003

Research Engineer

Introduce company

LMS provides solutions for functional performance: testing systems, multidisciplinary virtual prototyping software, engineering services and collaborative engineering tools that enable product refinement and process efficiency. LMS is partner of companies in the automotive, aerospace, and other manufacturing industries in the world. (http://www.lmsintl.com/

Intervention

Context A majority of noise and vibration problems in automotive and aeronautical manufactured products occur in the range between the low and high frequency, the so-called mid-frequency range. Deterministic method (Finite Elements Analysis) can lead to poor results as it has its frequency limitation.

Objectives • Explore the capabilities and limitations of deterministic method within the framework of vibro-acoustic prediction.

• Extend deterministic methods to the mid-frequency range by improving the performance in determination of the fluid-structure interface.

• In the particular case of a reduction technique called ‘modal expansion’: Investigate the projection quality structural modes onto the interface between the structural and acoustical meshes to achieve a fluid-structure coupling, so-called “Mesh Mapping” procedure.

Actions Part 1: ‘Wetted’ surface determination (fluid-structure interface)

• Achieve preliminary training phase on commercial FE and post-processing software (Nastran, Virtual.Lab).

• Develop with programmers geometrical processes to tackle non-conformity problem of the determination of the wetted surface.

• Assess the performance of two procedures (so-called ‘node-to-node’ and ‘rectangular’ coupling) by running computation on different vibro-acoustics configurations.

• Investigate the coupling quality by running data analysis scripts on MATLAB.

Part 2: “Mesh Mapping” procedure.

• Investigate five different mapping schemes. Emphasis of the importance of particular coupling parameters in the node interpolation process.

• Develop indicators for mapping quality inspired from ‘Modal Assurance Criterion’. Compute this indicators by running developed MATLAB scripts.

Results • Features now implemented in Virtual.Lab helping NASTRAN to define the fluid structure interface before starting to solve the coupled system. Reach a gain time in the coupling procedure and therefore gain some bandwidth in frequency range.

• Indicators constitute good relative clues of projection schemes when they are computed in one defined case of study.


Mathematical development environment: MATLAB scripts.


Page 16 of 19

Management/Execution of environmental noise assessment and noise mapping for Six-Flags Belgium attraction park

ATS-Bureau d’ingénieurs conseil en acoustique et traitement du signal, Liège, Belgium, March 2002-October 2002

Project Engineer

Introduce company

ATS is a consultancy company providing acoustics, noise and vibration solutions to architectural and environmental projects. Working in collaboration with architects, ATS specialists provide advice and design on issues of noise control and of performance spaces for offices, theatre or entertainment. Expertise also encompasses environmental noise issues. (http://scala-ats.com/)

Intervention

Context Six-flags Belgium attraction park located in Wavres was encountering issues with its noise impact in the neighbouring population. In order to fulfil requirements of environmental regulations and answers to neighbourhood complaints as well as providing noise abatement solutions, a noise mapping of the park was achieved.

Objectives • Realise noise level measurements of functioning attractions to assess noise emission and measurements at locations in the neighbourhood to assess resulting noise propagation.

• Localise source and occurrence of high noise level emission of attractions and diagnosis its impact on the global noise level at park frontiers.

• Provide noise abatement solution for critical noisy attractions.

Actions • Organise noise measurement campaign at Six-flags Belgium park during opening and closing hours and at neighbouring resident’s property.

• Estimate analytically noise power levels from noise pressure level measurements taken at different defined points in park.

• Contact geographical authorities for information, map and numerical data on relief, house implantation and weather.

• Gather information from residents on park’s noise emergence.

• Simulate noise environmental impact by achieving a noise mapping with IMMI dedicated software. Take into account cadence of runs of attractions, directivity of noise emission, relief, buildings’ dimensions and absorptions.

• Corroborate noise level predictions from results with measurement taken at residents’ property.

• In accordance to the legislative regulations on environmental noise policy, propose multiple design solutions to Six-flags Belgium and suggest fitted runs’ cadences in order to comply with noise regulations.

Results • Answer to neighbourhood resident’s request on assessing noise pollution provoked by the running of attractions park.

• Provide reference noise mapping for further legislative decision.

• Propose the company solutions to comply with noise regulations.


Page 17 of 19

Management/Execution of passive noise and vibration control studies for architectural projects. Contribution to the development of active control of sound through wall partitions

ATS-Bureau d’ingénieurs conseil en acoustique et traitement du signal, Liège, Belgium, October 2001-February 2002

Project Engineer

Introduce company

ATS is a consultancy company providing acoustics, noise and vibration solutions to architectural and environmental projects. Working in collaboration with architects, ATS specialists provide advice and design on issues of noise control and of performance spaces for offices, theatre or entertainment. Expertise also encompasses environmental noise issues. (http://scala-ats.com/)

Intervention

Context In the building industry, the so-called “passive” noise and vibration control is now of major importance. As concerns for acoustical comfort grows, architects and/or other construction companies nowadays require consultancy services in noise and vibration.

Objectives • Provide expertise to client (architects or third party) in noise insulation performance of windows, wall partitions, design of silencer in HVAC, absorption of materials.

• Answer to “cahier des charges” which set vibration and acoustical performance of buildings.

Actions • Establish a diagnosis of on-site noise situation.

• Gather information on architectural plan.

• Execute analytical computation of noise and/or vibration insulation performance of architectural design, reverberation time.

• Propose design solutions to achieve targeted noise insulation of rooms, vibration insulation of floors and roofs (dimensions, materials, thickness).

• Propose design solutions to achieve targeted acoustical comfort of rooms, reverberation time, NR index (acoustical absorption and reflection of materials).

• Assess products performance (doors, windows, walls partitions) by measuring Transmission Loss Factor on site or in laboratory according to the standards.

• Help the client to select the best design and cost.

• Follow up of good achievement of design recommendation during the construction phases.

Results • Bring satisfaction to client by answering to his “cahier des charges” requirements in noise and vibration.

Others information

Contribution to a research program in partnership with the University of Liege: Assessment of passive performance of wall partitions and contribution to the design of an active control system embedded in the partitions.

Working environment

Building and technical industries, Architecture.


Page 18 of 19

HRTF measurements and development of the so-called “Optimal Source Distribution” audio system devoted to 3D sound environment rendering

Institute of Sound and Vibration Research, University of Southampton, United Kingdom, January 2001–July 2001

Research Assistant

Introduce company

The Institute of Sound and Vibration Research is one of Europe’s leading centres for noise and vibration technology. The ISVR provides academic teaching in engineering acoustics, dynamics, human hearing and digital signal processing. Four research groups are respectively active in Human Sciences, Dynamics, Signal Processing and Control, and Fluid Dynamics and Acoustics. The Fluid Dynamics and Acoustics research group has for the last ten years been working on using digital signal processing to improve the quality of sound reproduction systems. The ultimate goal is to be able to produce the illusion in a listener of being in a "virtual" acoustic environment which is entirely different from that of the space in which the listener is actually located.

Intervention

Context The optimal source distribution (OSD) system can overcome a number of problems often associated with binaural synthesis over loudspeakers (loss of dynamic range, deterioration of control performance by small errors and room reflections). It is based on the acoustic principle of cross-talk cancellation and confers the 3D sound field to be synthesised by three different pairs of loudspeakers and by the use of a crossover filter (practical implementation of a conceptual monopole transducer pair whose span varies as a function of frequency). In order to render the virtual sound images, the so-called “plant matrix”, embodying the electro-acoustic path that constitutes the loudspeakers, the crossover filter and the propagation of the resulting sound in free-field conditions, must be inverted.

Objectives • Head Related Transfer Functions (HRTF) must preliminary be measured in order to invert the system’s plant thereafter and design the ‘inverse’ filter.

• Validate the effectiveness of the system inversion which highly depends on the exactitude of the HRTF measurements.

Actions • Proceed the Head Related Transfer Functions measurements in anechoic room (free-field conditions): i.e. transfer function measurements between system channels and microphones located in the pinnae ear canal simulators of dummy head.

• Control and perform system inversion for filter design by processing measurements with MATLAB scripts.

Results • Avoid source of errors in HRTF measurements which could be relevant to the dysfunction of the system (starting point of inverse filters design).

• Improvement in sound quality: better spatial perception and robust control performance over wider frequency range which led to better synthesis of time and frequency domain localisation cues.

• The audio system description is provided on the ISVR Virtual Acoustics Project web page (http://www.isvr.soton.ac.uk/FDAG/VAP/index.htm)


Digital Signal Processing for audio development, Binaural Synthesis technology.


Page 19 of 19

EDUCATION & TRAINING

2009 Computer-aided design Course: AutoCAD Architecture, Brussels - Belgium

2006 C Programming Course. Philips CTT center, Eindhoven – Nederland

2004 LMS internal Course on Aero-acoustics. LMS International, Leuven – Belgium

2003 ISMA Course on Modal Analysis. Katholieke Universiteit, Leuven – Belgium

2001 Course on Room Acoustics. University of Ferrara - Italy

2001 Modular Courses in Digital Signal Processing:

• Non-Stationary and Non-linear Methods in Digital Signal Processing

• Measurement Technology and Instrumentation

• Introduction to DSP design

Institute of Sound and Vibration Research, University of Southampton – United Kingdom

2001 MSc. in Sound and Vibration Studies http://www.isvr.soton.ac.uk/

Institute of Sound and Vibration Research, University of Southampton – United Kingdom

The Masters involved study and research in the fields of engineering acoustics and

structural dynamics. The teaching was based on the following main topics:

• Analytical and Numerical Acoustics

• Active and Passive Control of Sound and Vibration

• Digital Signal Processing

and was concluded by a written dissertation of a research project.

1999 Licence es Sciences Physiques (3rd year, equivalent to BSc. in Physics)

Faculté Libre des Sciences. Université Catholique de Lille – France

1998 DEUG “Sciences de la Matière” (2 years Diploma in Maths and Physics)

Faculté Libre des Sciences. Université Catholique de Lille – France

PUBLICATIONS ‘An Iterative Solution Technique for Coupled Vibro-acoustic Analysis’,

Institute of Acoustics Spring conference 2004, Southampton, United Kingdom

http://users.skynet.be/thomas.peuvrel/download/Paper_IoA_2004.pdf

MSc. Dissertation: ‘Noise in MRI scanners’, Institute of Sound and Vibration Research, 2000

http://users.skynet.be/thomas.peuvrel/download/MSc_dissertation.pdf

Documents

Engineer in Acoustics, Noise and Vibration, Structural ...users.skynet.be/thomas.peuvrel/download/Thomas_Peuvrel_competen… · Acoustics, Noise and Vibration, Structural Dynamics,