NF ISO 20270
Acoustics - Characterization of sources of structure-borne sound and vibration - Indirect measurement of blocked forces
This document specifies a method where a vibrating component (a source of structure-borne sound or vibration) is attached to a passive structure (or receiver) and is the cause of vibration in, or structure-borne sound radiation from, the assembly. Examples are pumps installed in ships, servo motors in vehicles or machines and plant in buildings. Almost any vibrating component can be considered as a source in this context.Due to the need to measure vibration at all contact degrees of freedom (DOFs) (connections between the source and receiver), this document can only be applied to assemblies for which such measurement is possible.This document is applicable only to assemblies whose frequency response functions (FRFs) are linear and time invariant.The source can be installed into a real assembly or attached to a specially designed test stand (as described in 5.2).The standard method has been validated for stationary signals such that the results can be presented in the frequency domain. However, the method is not restricted to stationary signals: with appropriate data processing, it is also applicable to time-varying signals such as transients and shocks (provided linearity and time invariance of the FRFs are preserved).This document provides a method for measurement and presentation of blocked forces, together with guidelines for minimizing uncertainty. It provides a method evaluating the quality of the results through an on-board validation procedure but does not comment on the acceptability or otherwise of the results.
This document specifies a method where a vibrating component (a source of structure-borne sound or vibration) is attached to a passive structure (or receiver) and is the cause of vibration in, or structure-borne sound radiation from, the assembly. Examples are pumps installed in ships, servo motors in vehicles or machines and plant in buildings. Almost any vibrating component can be considered as a source in this context.
Due to the need to measure vibration at all contact degrees of freedom (DOFs) (connections between the source and receiver), this document can only be applied to assemblies for which such measurement is possible.
This document is applicable only to assemblies whose frequency response functions (FRFs) are linear and time invariant.
The source can be installed into a real assembly or attached to a specially designed test stand (as described in 5.2).
The standard method has been validated for stationary signals such that the results can be presented in the frequency domain. However, the method is not restricted to stationary signals: with appropriate data processing, it is also applicable to time-varying signals such as transients and shocks (provided linearity and time invariance of the FRFs are preserved).
This document provides a method for measurement and presentation of blocked forces, together with guidelines for minimizing uncertainty. It provides a method evaluating the quality of the results through an on-board validation procedure but does not comment on the acceptability or otherwise of the results.
Le présent document spécifie une méthode dans laquelle un composant vibrant (une source de bruit solidien ou de vibrations) est fixé à une structure (ou récepteur) passive et provoque des vibrations dans l'assemblage ou un rayonnement sonore solidien de l'assemblage. Des pompes installées dans des navires, des servomoteurs dans des véhicules ou des machines et une installation dans des bâtiments en sont des exemples. Presque tous les composants vibrants peuvent être considérés comme une source dans ce contexte. En raison de la nécessité de mesurer les vibrations à tous les degrés de liberté (DDL) de contact (connexions entre la source et le récepteur) , le présent document ne peut s'appliquer qu'aux assemblages pour lesquels un tel mesurage est possible.
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1 Domaine d'application
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2 Références normatives
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3 Termes et définitions
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4 Sélection des degrés de liberté (DDL)
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5 Montage d'essai
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6 Appareillage de mesure
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7 Mode opératoire d'essai
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8 Procédure d'analyse
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9 Incertitudes et validation
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10 Rapport d'essai
- Annexe A Exemple de rapport d'essai: entraînement électrique de l'essieu arrière d'une voiture particulière; analyse des voies de transfert (TPA) et estimation des forces bloquées in situ conformément à l'ISO 20270:2019
- Annexe B Essais de la validité des données de mesure
- Annexe C Études de cas
- Annexe D Critères de sélection des DDL d'indicateur et de validation
- Annexe E Prévision du bruit et des vibrations
- Bibliographie
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