2014 European Altair Technology Conference
June 24-26, 2014 | Munich, Germany
Join, Contribute, Exchange
Brake Noise Simul...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2013 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engine...
Upcoming SlideShare
Loading in …5
×

Brake Noise Simulation using Multibody Simulation Analysis

934
-1

Published on

The level of noise transmitted to the passengers of a vehicle can drastically impact a passenger’s comfort. Brake noise will give the customer an impression of poor product quality and can thus damage the quality image of the company. Within the automotive industry, the study of mode coupling instability by the use of FEM and modal complex analysis is widespread to reduce those phenomenon.

In this paper an alternative method is presented, where potential brake noise issues are predicted by the use of a time transient integration using multi-body system analysis. The simulation model contains a non-linear contact description, bushing, flexible bodies and the axis cinematic of the vehicle. Transient results are transformed by Fourier for a frequency domain study. The parameters that can be varied for the prediction analysis are brake pressure, vehicle speed, friction laws, system damping and bushing properties.

The advantages of the multi-body system analysis approach are in the direct consideration of the non-linearity’s which are significant within certain frequency ranges. The multi-body system analysis approach also provides a further method to confirm results from the complex modal analysis and thus increases the informational value of the numerical predictions.

Simulations variant results will be presented and discussed and enhancements will be proposed.

Published in: Engineering, Business, Technology
0 Comments
2 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
934
On Slideshare
0
From Embeds
0
Number of Embeds
6
Actions
Shares
0
Downloads
30
Comments
0
Likes
2
Embeds 0
No embeds

No notes for slide

Brake Noise Simulation using Multibody Simulation Analysis

  1. 1. 2014 European Altair Technology Conference June 24-26, 2014 | Munich, Germany Join, Contribute, Exchange Brake Noise Simulation using Multi-Body Simulation Analysis Dr. Armin Veitl Benjamin Leblanc See full agenda: www.altairhtc.com/europe
  2. 2. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Agenda • Motivation • Self excited system • Tribology effects • Contact modeling • Model build-up • Simulation setting with a driving rotation • Results & discussion • Planed enhancements
  3. 3. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Motivation • The level of noise heard within a vehicle’s interior can drastically impact a passenger’s comfort. Brake noises can give the customer a poor impression of product quality. Within the C.A.E. industry, the study of mode coupling instability by the use of F.E.M. and modal complex analysis, is widespread to reduce those phenomenon. • An complementary method is presented in this paper where brake noise issues are predicted by the use of a time transient integration using multi-body system analysis
  4. 4. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2013 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Brake - Vibration and Noise Judder Moan Groan Low Frequency Squealing High Frequency Squealing 10 100 500 1k 3-4k 10k Typeofoscillation forcedself-excited Frequency [Hz] Low frequency Effects High frequency Effects Usual application field for MBD Domain that we intend to cover
  5. 5. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Brake - Vibration and Noise Brake Squeal Issue CAE model – CAE Labor Differential Equation of motion Linearization and Instability Analysis Frequency Domain Results: Frequency of instability complex mode shape Integration of the differential equation system Time Domain Results: Analyze by Fourier in frequency domain time shape animation Problem Identification / Engineering a solution
  6. 6. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Self excited system • Phenomena that leads from a steady state to an oscillatory state without external oscillatory excitation • Comparison to aero-elasticity “Limit Cycle Oscillations (LCO)” Excitation system pad ↔ disc (stick-slip effect) Resonant system suspension Input: - vehicle speed - brake pressure - friction law Output: - resonance phenomena - brake noise Feedback loop: - suspension vibration self-excited system LCO pictures source: Wind tunnel analysis of separated aerodynamcis leading to different types of torsional flutter in bluff-bodies, T. Andrianne – Université of Liège Animation Gif source: AcuSolve Example – Altair Engineering constant flow section from a beam
  7. 7. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Tribology effects • Tribology is the science of interacting surfaces in relative motion pictures source: Thèse: Apport des analyses numériques temporelle et fréquentuelle dans l´étude des instabilités de contact, A.Meziane Animation Gif source: Arnol'd tongues arising from a grazing-sliding bifurcation of a piecewise-smooth system, Szalai, R; Osinga, HM, University of Bristol self-oscillations that appears due to contact can be classified in 2 categories: • stick-slip vibration • quasi-harmonic vibration stick-slip vibration quasi-harmonic vibration Normal force on pad Friction force on pad friction law example Ft = µ(v).Fn
  8. 8. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Contact modeling • Friction Law • Flexibility of the disk • Flexible surface: • a marker can slide along the whole surface • surface deformation is interpolated between reference points • A modal basis provides the stiffness of the surface. Static correction modes are not required for the surface • Static correction modes only used for the connection to the strut … mode 7 mode 8 mode 9 mode 10 mode 11 mode 12
  9. 9. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Contact modeling • Friction Law • Flexibility of the disk • User-Subroutine • Compute normal force at contact point • Compute friction force at this point Python Script: no compilation required Call of the User-Subroutine in MotionSolve
  10. 10. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Model build-up Mac-pherson axle system Strut idealized as one flexible body control arm as one flexible body … … toe link modeled with a poly-beam connected with a ball and a constant velocity joints All bushings parameterized with a dataset
  11. 11. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Model build-up floating brake caliper system Brake caliper as flexible body Brake bracket as flexible body … … Brake piston as a rigid body Brake pads as flexible too Disk and hub as one flexible body and modeled with deformable surface as shown on a previous slide
  12. 12. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Simulation setting with a driving rotation • Virtual actuator • 2 degree of freedom • Impose rotation • Constant velocity • 2 [km/h] • brake disk free to move in other directions • Brake pressure • Constant 20 [bar] • Simulation settings • Transient : 2 [sec] • Integrator : DSTIFF constant velocity joint constant velocity joint revolute joint attached to GROUND motion boundary condition translational joint attached to DISK Body 1 Body 2 Body 3
  13. 13. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. The model in HyperWorks model database structured with a browser All contact instance included in is own system Dataset to manage input parameter Axle and Brake separated into 2 systems to enable easy model update Virtual system to rotate wheel GUI entry to manage simulation variants
  14. 14. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Results & discussion • Relative speed at contact point between pad and disk surface • Stick-slip characteristic • increasing area until constant amplitude • Stick area • Slip area • “quasi-harmonique” STICK STICK STICK SLIP SLIP SLIP SLIP transition
  15. 15. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Results & discussion Results animation : friction directions are changing when system start vibrating the displayed forces are applied on pad
  16. 16. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Results & discussion Results animation : friction directions are changing over time, but system behaves quasi-harmonic the displayed forces are applied on pad
  17. 17. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Results & discussion • Acceleration time history can be filtered by Fourier and displayed in water fall diagram in a frequency range from [0 – 4000 Hz] • Critical frequencies appear in the diagram and can be compared to component normal frequency or complex modes 1 3 2
  18. 18. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Results & discussion Results animation : scale 500 in deformation, deformation shapes can be compared to normal modes or to complex modes analysis
  19. 19. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Results & discussion • Brake Noise Simulation: Resume of the CAE-Knowledge • Finite element modal complex • Multi-body FFT‘s 1
  20. 20. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Results & discussion • Brake Noise Simulation: Resume of the CAE-Knowledge • Finite element modal complex • Multi-body Instable mode animation with FE modal complex (Frequency domain) Time animation with Multi-body Simulation 1
  21. 21. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Process Implementation pictures source: http://www.ganttproject.biz GanttProject is a cross-platform desktop tool for project scheduling and management. • Implementation in vehicle development • build on existing CAE information: no double effort to invest • win twice more information on the same project • CAE tasks can be performed in parallel and validate each other • increase CAE predictivity / reporting value from CAE Labor
  22. 22. Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.Copyright © 2012 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Results & discussion • Summary • multi-body simulation method enable self excited system simulation • “Stick-Slip” characteristics clearly shown • frequency responses appear in the expected range [0Hz – 4000 Hz] • the method matured for vehicle development • enable comparison with modal complex analyze / reciprocal validation of CAE • Planed enhancements • Post-processing tools to more easily identify the critical peak • Automation to enable better model build-up
  1. A particular slide catching your eye?

    Clipping is a handy way to collect important slides you want to go back to later.

×