This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Robust NVH Engineering Using Experimental Methods - Source Characterization Techniques for Component Transfer Path Analysis and Virtual Acoustic Prototyping
ISSN: 0148-7191, e-ISSN: 2688-3627
Published June 5, 2019 by SAE International in United States
Annotation ability available
A major challenge in automotive NVH engineering is to approach complex structure-borne sound and vibration problems with sufficient accuracy but reasonable experimental effort. Typical issues encountered are poor correlation between objective component performance criteria tested for during bench validation and corresponding subjective targets evaluated during system validation in the actual vehicle. Additional challenges arise from the need to impose assumptions on sophisticated physical vibration problems to reduce the complexity to a level feasible for conventional experimental test methods. This paper addresses all mentioned issues by elaborating on a system NVH engineering approach employing Virtual Acoustic Prototyping (VAP) (related to what is now often called component Transfer Path Analysis) to synthesize time domain sound and vibration responses of vibrating machinery operated in a virtual vehicle environment. One crucial step of VAP is to characterize the strength of vibrating machinery by independent quantities at the significant coupling degrees of freedom (DoF). This study puts special focus on the measurement of free velocity, suitable for machinery operated when resiliently mounted as per ISO 9611, and the in-situ measurement of blocked forces, applicable for sources connected to any type of receiving structure during operation, as per ISO/DIS 20270. In order to reduce complexity of the underlying measurements this paper investigates the possibility of using collocated sensor arrays and methods to validate assumptions imposed to abstract away from rotational coupling DoF. An electric power steering (EPS) system inducing vibrations into a sub-frame-type structure is considered as a representative automotive source-receiver installation to investigate the feasibility of free velocity and in-situ blocked force approach with respect to independent source characterization for component Transfer Path Analysis (TPA) and VAP. The obtained Virtual Acoustic Prototype is expanded using an algorithm to synthesize realistic time domain data, enabling NVH engineers to conduct reliable objective and subjective design evaluations.
CitationWienen, K., Sturm, M., Moorhouse, A., and Meggitt, J., "Robust NVH Engineering Using Experimental Methods - Source Characterization Techniques for Component Transfer Path Analysis and Virtual Acoustic Prototyping," SAE Technical Paper 2019-01-1542, 2019, https://doi.org/10.4271/2019-01-1542.
- Moorhouse, A.T. , “Virtual Acoustic Prototypes: Listening to Machines that don't Exists,” Acoustics Australia 33(3):97, 2005.
- Sturm, M., Alber, T., Moorhouse, A.T., Zabel, D. et al. , “The In-Situ Blocked Force Method for Characterization of Complex Automotive Structure-Borne Sound Sources and Its Use for Virtual Acoustic Prototyping,” in ISMA 2016, Belgium, Sep. 19-21, 2016.
- van der Seijs, M.V., de Klerk D., and Rixen D.J. , “General Framework for Transfer Path Analysis: History, Theory and Classification of Techniques,” Mechanical Systems and Signal Processing 68 (217-244), 2016.
- de Klerk, D., Rixen, D.J., and Voormeeren, S.N., “General Framework for Dynamic Substructuring: History, Review and Classification of Techniques,” AIAA Journal 46 (5):1169-1181, 2008.
- The International Organization for Standardization (ISO) , “Acoustics - Characterization of Sources of Structure-Borne Sound with Respect to Sound Radiation from Connected Structures - Measurement of Velocity at the Contact Points of Machinery When Resiliently Mounted,” BS ISO 9611:1996, 1996.
- Moorhouse, A.T., Elliott, A.S., and Evans, T.A. , “In Situ Measurement of the Blocked Force of Structure-Borne Sound Sources,” Journal of Sound and Vibration 325(4-5):679-685, 2009.
- The International Organization for Standardization (ISO) , “Acoustics - Characterization of Sources of Structure-Borne Sound and Vibration - Indirect Measurement of Blocked Forces,” ISO/DIS 20270:2018(E), 2018.
- Wernsen, M.W.F., van der Seijs, M.V., and de Klerk, D. , “An Indicator Sensor Criterion for In-Situ Characterisation of Source Vibrations,” . In: Sensors and Instrumentation. Vol. 5. (Cham, Springer, 2017), 55-69.
- Meggitt, J.W.R., Elliott, A.S., and Moorhouse, A.T. , “A Covariance Based Framework for the Propagation of Uncertainty Through Inverse Problems with an Application to Force Identification,” Mechanical Systems and Signal Processing 2018.
- Meggitt, J.W.R., Moorhouse, A.T., and Elliott, A.S. , “On the Problem of Describing the Coupling Interface Between Sub-Structures: An Experimental Test for ‘Completeness’,” . In: Dynamics of Coupled Structures. Vol. 4. (Cham, Springer, 2018), 171-182.
- Elliott, A.S., Moorhouse, A.T., and Pavić, G. , “Moment Excitation and the Measurement of Moment Mobilities,” Journal of Sound and Vibration 331(11):2499-2519, 2012.
- Moorhouse, A.T., Evans, T.A., and Elliott, A.S. , “Some Relationships for Coupled Structures and their Application to Measurement of Structural Dynamic Properties In Situ,” Mechanical Systems and Signal Processing 25(5):1574-1584, 2011.
- van der Seijs, M., van den Bosch, D., Rixen, D., and de Klerk, D. , “An Improved Methodology for the Virtual Point Transformation of Measured Frequency Response,” COMPDYN, 2013.
- de Klerk, D., and Rixen, D.J. , “Component Transfer Path Analysis Method with Compensation for Test Bench Dynamics,” Mechanical Systems and Signal Processing 24(6):1693-1710, 2010.
- Elliott, A.S., Moorhouse, A.T., Huntley, T., and Tate, S. , “In-Situ Source Path Contribution Analysis of Structure Borne Road Noise,” Journal of Sound and Vibration 332(24):6276-6295, 2013.
- Lennström, D., Olsson, M., Wullens, F., and Nykänen, A. , “Validation of the Blocked Force Method for Various Boundary Conditions for Automotive Source Characterization,” Applied Acoustics 102:108-119, 2016.
- Alber, T., Sturm, M., and Moorhouse, A.T. , “Independent Characterization of Structure-Borne Sound Sources Using the In-Situ Blocked Force Method,” in Internoise 2016, Germany, Aug. 21-24, 2016.
- Sturm, M., Moorhouse, A.T., Yankonis, M., Marchand C. et al. , “Robust NVH Development of Steering Systems Using In-Situ Blocked Forces from Measurements with Low-Noise Driver Simulators,” in NOISE-CON 2017, USA, June 12-14, 2017.
- Moorhouse, A.T. , “Virtual Acoustic Prototypes as A Tool for Low-Noise Design,” Proceedings of the Institute of Acoustics 24(4), 2002.
- Meggitt, J.W.R. , “On In-Situ Methodologies for the Characterisation and Simulation of Vibro-Acoustic Assemblies,” Ph.D., University of Salford, Salford, UK, 2017.
- van der Seijs, M., Pasma, E.A., de Klerk, D., and Rixen D.J. , “A Robust Transfer Path Analysis Method for Steering Gear Vibrations on a Test Bench,” in ISMA 2016, Belgium, Sep. 7-9, 2014.
- Kimpián, T. and Augusztinovicz, F. , “Multiphase Multisine Signals - Theory and Practice,” in ISMA 2016, Belgium, Sep. 19-21, 2016.
- Moorhouse, A.T. and Meggitt, J.W.R. , “Evaluation of Uncertainties in Classical and Component (Blocked Force) Transfer Path Analysis (TPA),” SAE Technical Paper, 2019.
- Knechten, T., Morariu, M.-C., and van der Linden, P.J.G. , “Improved Method for FRF Acquisition for Vehicle Body NVH Analysis," SAE Technical Paper 2015-01-2262, 2015, doi:10.4271/2015-01-2262.
- Meggitt, J.W.R., Elliott, A.S., Moorhouse, A.T., Banwell, G. et al. , “Broadband Characterisation of In-Duct Acoustic Sources Using an Equivalent Source Approach,” Journal of Sound and Vibration 442:800-816, 2019.