Sound and Vibration Measurements: How-To Guide. Ce document fait partie du portail de ressources intitulé "Guide pratique sur les mesures les plus courantes". 1. Présentation générale sur les capteurs piézoélectriques (IEPE), l'acoustique et les vibrations Une vibration se produit quand une masse oscille de façon mécanique par rapport à un point d'équilibre.
Un exemple commun de système mécanique vibratoire est un système masse-ressort amorti, montré dans la figure 1. Des vibrations se produisent aussi sur des surfaces, comme les ailes d'un avion ou un gong. Dans la plupart des cas, les vibrations sont indésirées car elles causent une déperdition d'énergie, de la fatigue, du bruit et les systèmes sont généralement conçus pour minimiser ce type de vibrations. Figure 1. Le son et les vibrations sont essentiellement des oscillations dans différents médias et de la même façon que des vibrations peuvent créer du son, les ondes acoustiques qui se propagent dans l'air peuvent aussi générer des oscillations sur des matériaux solides. 2. 3. 4 Vibration measurement and prediction. Articles | How is Vibration Measured? | ReliabilityWeb.com: A Culture of Reliability. By Commtest Instruments In the last section we identified the most important vibration analysis tool as the spectrum. When we measure machine vibration we usually measure vibration spectra, since the spectrum of a vibrating component tells us a great deal about the condition of the component as well as about the cause of vibration.
Naturally it is vital that the spectrum, which gives such valuable information, be obtained accurately. What guidelines must be observed to ensure measurements are accurate? How should measurements be taken and for which machines should they be taken? In this section we will answer these questions.After reading this section you will be able to: Recognize which machines should be monitored Understand how vibration sensors should be mounted Determine how measurement parameters should be set Take measurements in a systematic way Which Machines Need Monitoring? When deciding which machines to monitor, critical machines should be given priority over other machines. A Practical Approach to Vibration Detection and Measurement Part 1: Physical Principles and Detection Techniques.
February 1, 1999By: Jon Wilson, The Dynamic Consultant, LLC This tutorial addresses the physics of vibration; dynamics of a spring mass system; damping; displacement, velocity, and acceleration; and the operating principles of the sensors that detect and measure these properties. Vibration is oscillatory motion resulting from the application of oscillatory or varying forces to a structure. Oscillatory motion reverses direction. As we shall see, the oscillation may be continuous during some time period of interest or it may be intermittent. It may be periodic or nonperiodic, i.e., it may or may not exhibit a regular period of repetition. The nature of the oscillation depends on the nature of the force driving it and on the structure being driven.
Motion is a vector quantity, exhibiting a direction as well as a magnitude. F = MA W = Mg K = F/d = W/d d = F/K = W/K = Mg/K Free Vibration. Two characteristic behaviors should be noted. Forced Vibration. Transmissibility. Tr = R/I Resonance. 1. And.
Condition Monitoring, Vibration MSending downloads measurement Analysis & Balancer. Noise and Vibration Analysis and Measurement. Brüel & Kjær Vibro: Measurement Techniques.