Powertrain session atc_2015
0 likes2,938 views
The document describes OptiStruct software for analyzing noise, vibration, and harshness (NVH) in powertrains. It discusses OptiStruct's capabilities for full vehicle and powertrain NVH simulation including normal modes analysis, frequency response, random response, transient analysis, acoustic analysis, and rotor dynamics. It also summarizes OptiStruct's interfaces to other NVH software, optimization capabilities, and automated reporting solutions.
Powertrain session atc_2015
- 1. OptiStruct for PT NVH
- 2. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Full Vehicle NVH Powertrain NVH Body/Chassis NVH Squeak & RattleWind Noise Radiated Noise Ride NVH Brake NVH OptiStruct solution for NVH Full Vehicle NVH Powertrain NVH Body/Chassis NVH Squeak & RattleWind Noise Radiated Noise Ride NVH Brake NVH
- 3. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. A comprehensive set of NVH solutions for upfront problem solving • Full frequency, multi-physics NVH simulation capabilities • Superior user experience in a highly integrated, automated framework • Population performance based assessment, instead of single sample • Optimization based design, instead of experience based design OptiStruct for Powertrain NVH
- 4. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. • A comprehensive high-performance FE-solver • NVH Solutions • Normal modes • Preloaded normal modes • Complex eigenvalue • Frequency response • Random Response • Transient Analysis • Acoustic Analysis • Rotor Dynamics • Solutions are “ready for optimization” • Interfaces to AMSES and FastFRS OptiStruct for Powertrain NVH
- 5. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. • OptiStruct AMSES fast eigenvalue solver • Calculate thousands of modes for millions of dof’s • Handles unconnected structures • Can be used with enforced motion (SPCD) • OptiStruct FASTFR frequency response solver • Include thousands of modes with viscous and/or structural damping • Works with frequency dependent materials • PARAM,FASTFR,(AUTO/ON/OFF) • No additional cost for AMSES or FASTFR OptiStruct for Powertrain NVH 0 20000 40000 60000 80000 AMSESLanczos elapsed time (s) AMSES VS Lanczos for Modal FRF solution Eigen Solution Structral Damping Other
- 6. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Total Sound Power • The total sound power is the rate of change of sound energy with time in the domain of reference • The total sound power due to all the source grids can be calculated at a microphone location for each frequency as follows
- 7. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Sound Pressure • Radiated Sound Output can be requested for grid points on the structural surface and in the exterior acoustic field. Grid points are used to represent microphones to record the radiated sound, sound power, and sound intensity.
- 8. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Sound Intensity • The total complex intensity vector is the sound power per unit area. The sound intensity can be defined as a product of sound pressure and the particle velocity vector • For multiple source grids, the total sound intensity at a microphone location for each frequency is given as follows
- 9. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Equivalent Radiated Power • Computation of the equivalent radiated power (ERP) is a simplified method to gain information about maximum dynamic radiation of panels for excitations in frequency response analysis. • The ERP output of a panel is calculated as half the normal velocity squared of each grid multiplied by the associated area of each grid on the panel.
- 10. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Noise and Vibrations • Frequency Dependant Materials • Direct and modal FRF • MATFx data • Rotor Dynamics Analysis • Modal frequency response and complex eigenvalue analyses • Synchronous and asynchronous analyses • Output data generation for the Campbell diagram (critical speeds) • Poro-elastic (BIOT) Materials • MATPE data
- 11. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. • Fast and accurate generation of AVL/EXCITE input data • Condensed matrices • FE model information • Grid Displacement and Stress • Directly coded in OptiStruct: • No DMAP, scripts, or macros required • AVL/EXCITE GUI for easy problem setup • Post AVL/EXCITE analysis to recover • Transient or frequency response stress and strain • Displacements, Velocities, and Accelerations in seconds • AMSES can be use for large problems OptiStruct Interface to AVL/EXCITE
- 12. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Post processing .fem or .bdf Model data/ matrices in ASCII or binary format (.OUT2, .OUT4, …) .exb .INP4 .h3d or op2 Flexbody .h3d Model building/ conversion MBD analysis Stress and Strain Recovery Flexible Body Generation .exb Generation HyperMesh Simlab OptiStruct AVL/EXCITE AVL/EXCITE OptiStruct Process scheme – OptiStruct AVL/EXCITE Coupling
- 13. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Optimization
- 14. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. • ERP available as an internal response in OptiStruct • Can also be applied to frequency sub-ranges • Topology optimization successfully applied to identify internal rib structure using ERP responses • Optimized design proposal shows a significant improvement in the ERP responses Summary
- 15. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Postprocessing
- 16. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. The goal of the Equivalent Radiated Sound Utility is to post process results of exterior structure-borne radiated sound - ERP H3D and PCH - Radiated Sound (Power / Pressure) H3D Equivalent Radiated Sound Utility
- 17. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Order analysis is a technique for analyzing noise and vibration signals in rotating or reciprocating machinery. Examples include aircraft and automotive engines, compressors, turbines, and pumps. Order analysis is an easy way to separate structural phenomena (resonances, fixed frequencies) from the rotational ones (variable frequencies). When presented in a frequency vs. rpm plot, you can see the resonances as parallel lines to the rpm axis and rotating frequencies as lines increasing or decreasing with speed (rpm). Engine Order Analysis
- 18. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Analyze • Worst case scenario • Critical components and locations exceeding the allowed thresholds • Effects of the latest design change Automated Reporting Solution Communicate • Share findings frequently • Right level of information • Consistent appearance Challenge Large amount of data/results Laborious repetitive tasks
- 19. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. Set-up 0.5 h Load Template, apply contour and adjust legend per component Refine/match ID’s and part/component names Verify model definition, e.g. material, properties Automated Reporting Solution Assessment 3.5 h Hotspot Finder or Measure Panel: Mark critical result locations Adjust to best view, create and save screenshot Review each component and identify critical components Report 2 h Import all screenshots into PPT master Create Overview Table Rearrange/format slides/layout
- 20. Copyright © 2015 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved. THANK YOU