P V SCAE
Drive Evaluate Understand Decide
Integrated powertrain developmentMeet whole vehicle targets up front
Evaluate contributions from different sources and paths
Analyse rotating components and structural vibration sources
Locate and quantify airborne sources
Fine tune, debug final prototypes, sign off for launch
www.bksv.com/automotive
Pre-concept Concept Design/Pre-hardware Development/Launch
Evaluate
Make the correct decision with high confidence
Understand
Communicate
Customer satisfaction
Customer preference
Competitor benchmarking
Rig testingDevelopment
testing
CAE predictions
Supplier data
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P
V
V
CAE S
CAE S
P V CAE
Evaluate NVH perception in authentic context
Enable customer clinics to assist with brand identification and customer-oriented, subjective target setting
Achieve consensus on brand sounds
Secure consensus within the engineering organisation on high level targets, especially relating to sound quality
Drive, evaluate, understand, decide Meet whole vehicle targets up frontThe PULSE NVH Vehicle Simulator portfolio is a set of tools for accurately reproducing the sound and vibration of a vehicle in a realistic interactive driving environment – quickly and cost-effectively.
Earlier concept evaluation
Simulator models created from test and Computer Aided Engineering (CAE) data can be used early in a vehicle programme, enabling evaluation of different design concepts before real-world data exists.
Include all stakeholders in the target setting process
Engineers, key decision makers and customers can drive and evaluate future NVH designs in the correct whole-vehicle context.
Perception-driven target setting
Non-experts can evaluate future NVH designs in the true whole-vehicle context, giving faster, better decisions, lower cost and risk, and clear consensus on targets.
Communicate design alternatives in human terms
Drivable simulator models enable you to communicate effectively, demonstrating design options and evaluat-ing what-if scenarios to reach consistent, balanced judgments at any stage of a vehicle programme.
Integrate powertrain development
An idealised NVH target vehicle can be used throughout the entire development process, with targets cascaded for different groups like powertrain engineers.
Modern trends like creating smaller engines that fulfil strict emissions standards and produce more power bring numer-ous Noise Vibration and Harshness (NVH) challenges. Higher combustion forces, lower mass and new technologies can significantly alter the sound character of an engine.
An NVH simulator helps manage the complete development process by accurately recreating the driving experience and the sound that the driver will hear in real-time, based on data from rig testing, measured on-road vehicle data, and CAE model data.
With it, the effects of engine downsizing can be anticipated and experienced long before a representative prototype vehicle is built. The sound character of the whole vehicle can be tuned and adjusted based on the new powertrain, and targets can be set and monitored throughout the design process – and cascaded down for individual components.
Desktop NVH Simulator allows people to drive and evaluate detailed models for target or benchmark vehicle assessments.
• Change vehicles with one click • Assess virtual prototypes early on
Full-vehicle NVH Simulator lets stakeholders experience sound and vibration models in an actual stationary vehicle with a projected real-time driving scenario.
• Feel accurately simulated vibration
On-road Vehicle NVH Simulator evaluates the power-train harmonics of simulation models while driving a real vehicle – for the highest authenticity.
• Adjust sounds in real-time
PULSE NVH Vehicle Simulator
Exterior Sound Simulator auralises virtual exterior sound of moving vehicles to design and evaluate appropriate sounds for both quiet vehicles and ICE brand quality considerations.
• Evaluate alternatives with jury tools
Customer
Bring the customer’s voice into the engineering process
Enable customer preference studies
Assist target validation
Manage-ment
Engage key decision-makers directly in the NVH process
Get confident, robust engineer-ing decisions – including target sign-off
Powertrain engineer
Receive detailed NVH data from test and CAE integrated in the vehicle evaluation models
Vehicle engineer
Get quick target consensus among key stakeholders
Ensure clearly communicated targets and knowledge-sharing between departments
CAE engineer
Experience the real effects of any predicted CAE modifications
Supplier
Evaluate components (virtual or physical) in whole vehicle context
Communicate efficiently between supplier and vehicle manufacturer
Source path contribution tools
P V SCAE V PV CAE
Feed signature analysis findings back into the simulator
Constantly refine simulation models
Evaluate proposed engineering changes
Update CAE models using finite element correlation
Angle-domain analysis functions include cycle statistics such as min/max/mean/RMS/Peak-peak vs. cycle number
Pre-concept Concept Design/Pre-hardware Development/LaunchPre-concept Concept Design/Pre-hardware Development/Launch
Envelope and cepstrum analysis diagnoses repetitive movement patterns – such as in bearings
Angle-domain analysis allows cycle extraction and visualisation of data as a function of crank angle
Structural validation Machinery diagnostics
Modal testing checks targets are met and analyses vibration modes using state-of-the-art curve-fitting algorithms
Operating Deflection Shapes shows dynamic vibration patterns under operating conditions such as idle, constant speed or run up/coast down
Operational Modal Analysis provides modal parameter and shape estimation from operational measurements
Evaluate contributions from different sources and paths
Analyse rotating components and structural vibration sources
Predicting the engine sound for the driver and passengers is possible with Source Path Contribution (SPC) technology, which determines the individual contributions from engine mounts, intake, exhaust, and various engine surfaces.
Our unique time-domain SPC technology plays back engine sound contributions as they would be heard at the driver’s ear, and can predict interior levels from engine sound and vibration measured on a test bench, or in a vehicle.
An NVH simulator can combine data from a mixture of different sources including detailed SPC data, CAE data and decomposed in-vehicle sounds. The simulator model can thus be tailor-made for a given troubleshooting purpose, whether tuning intake/exhaust orifice sound, optimising engine mounts, or studying noise transmission paths. In turn, this facilitates effective cascading of responsibility between departments.
Rotating components are always potential noise and vibration sources. Their relative annoyance levels can be assessed in the simulator to set vehicle level-targets, but understanding how to meet those targets requires different tools.
The first step in a root cause analysis may use Operating Deflection Shapes to show how the engine and key components move at troublesome speeds and loads. Detailed analysis to understand the mechanisms contributing to particular noise issues can use Operational Modal Analysis to derive structural dynamic properties from an operating test. And classical modal analysis can provide a deeper insight into structural dynamics and a link to CAE analysis to solve design problems.
Engine, driveline, or front-end accessory NVH issues may benefit from analysis in the angle domain. Crank angle analysis can give insights into engine noise or vibration where the root cause may be related to combustion or mechanical excitation. Envelope and cepstral analysis provide insights into gear train and bearing issues.
Listen to individual source paths
Hear and assess the importance of individual sources and paths
Cascade NVH development responsibility (for example between vehicle NVH, powertrain NVH and system suppliers)
Easily communicate issues between engineering teams
Demonstrate developments to stakeholders
SPC Time Insight isolates sound paths, allowing you to switch them on and off, and listen over a time or RPM range. With it you can compare different sets of results back-to-back from the same or different tests. Modifications to the individual contributions of each noise path are easy to make using high-pass, low-pass, band-pass, notch, or user-defined FIR filters.
• Real-time playback, processing, modification and analysis
• Off-line processing, modification and analysis
Exterior Noise Contribution Analysis shows contributions of individual sources to the overall external noise signature of the vehicle. It is measured on a dynamometer at indoor pass-by microphone positions.
• Quickly and accurately quantifies noise source vs distance in the pass-by position
• Ready for the new pass-by legislation, which will increase the applicability of indoor pass-by testing
P V V
Ensure brand-appropriate signature with the customer
Mitigate issues with meeting quantitative targets
Listen for perceived quality assessment
Replay validation measurements in simulator
Pre-concept Concept Design/Pre-hardware Development/LaunchPre-concept Concept Design/Pre-hardware Development/Launch
Beamforming makes fast, ‘single-shot’ mapping of noise sources with an acoustic array
Crank angle analysis shows sound intensity versus time/crank angle using time-domain holography
Noise source identification technologies
Microphone arrays can get close to sources thanks to removable sections – among many models available from Brüel & Kjær
Sound quality metrics mapping projects subjective sound quality parameters onto physical objects, such as loudness and impulsiveness (for diesel engines)
Acoustic holography transforms sound data into a detailed 3D description of the sound field
Conformal mapping overlays holographic maps on a 3D object for simple comprehension
Spherical beamforming provides 360-degree acoustic mapping overlaid on an image taken using built-in cameras
P V S
Drive – Evaluate – Understand – Decide
Customer preference
Vehicle level targets
Target sign-offIdentify
component changes
Develop engineering solutions
Validate and sign-off proposed changes
P V SCAE
Locate and quantify airborne sources
Fine tune, debug final prototypes, sign off for launch
Once the key NVH issues have been identified, the challenge is to understand them and find their origins – an area where noise source identification using array acoustics plays a vital part.
Brüel & Kjær is a pioneer of array acoustics technology, and we have developed a suite of sophisticated tools for locat-ing and quantifying airborne noise sources in operating conditions. Array acoustics data such as that from individual panel contributions can be assessed while driving the NVH simulator model.
To the non-expert, this type of analysis is easy to understand as contributions can be switched on and off while driv ing in an NVH simulator – assisting rapid decisions.
For resolving final-stage issues prior to launch, an NVH simulator can help engineers demonstrate changes in the context of the whole vehicle’s NVH, so decision-makers can understand the cost-benefit balance of potential solutions. The result is consensus in the process and greater confidence in decisions and final sign-off.
After launch, cost reduction can be a major challenge when no degradation of performance is permitted. Individual cost reduction measures may have little effect, but when combined with others can degrade NVH significantly. NVH simula-tors can help make a balanced assessment of a collection of individual cost reduction measures, to find the optimal combination that has the least impact on NVH while delivering the desired cost savings.
An NVH simulator can thus play a part in every stage of
the development process, supported by specialist tools
when deeper root-cause analysis is necessary.
When integrated into an NVH simulator model, results
from all of these tools can be experienced just as the customer
would experience them – while driving the car.
Implement and validate acoustical engineering changes
Quantify critical acoustics sources in the powertrain and other components
Investigate the effects of acoustical packages
Evaluate changes during realistic driving conditions
HEADQUARTERS: Brüel & Kjær Sound & Vibration Measurement A/S · DK-2850 Nærum · DenmarkTelephone: +45 77 41 20 00 · Fax: +45 45 80 14 05 · www.bksv.com · [email protected]
Local representatives and service organisations worldwide
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Brüel & Kjær is a world-leading manufacturer and supplier of sound and vibration measurement systems.
We help our partners and customers measure and manage the quality of sound and vibration in products and the environment. Our focus areas are automotive businesses, ground transportation, aerospace, space, defence, airport environment, urban environment, telecom and audio.
Brüel & Kjær has an unparalleled portfolio of sound and vibration measuring equipment and is a renowned deliverer of innovative instrumentation solutions.
With more than 90 sales offices or local agents in 55 countries, and eight ac-credited calibration centres worldwide, we provide immediate and comprehensive customer support.