scholarly journals Entropy in sound and vibration: towards a new paradigm

2017 ◽  
Vol 473 (2197) ◽  
pp. 20160602 ◽  
Author(s):  
A. Le Bot
Keyword(s):  
Statistical Theory ◽  
Classical Theory ◽  
Energy Analysis ◽  
Vibrational Energy ◽  
Simple Theory ◽  
Statistical Energy Analysis ◽  
New Paradigm ◽  
Elastic Structures ◽  
The Status

This paper describes a discussion on the method and the status of a statistical theory of sound and vibration, called statistical energy analysis (SEA). SEA is a simple theory of sound and vibration in elastic structures that applies when the vibrational energy is diffusely distributed. We show that SEA is a thermodynamical theory of sound and vibration, based on a law of exchange of energy analogous to the Clausius principle. We further investigate the notion of entropy in this context and discuss its meaning. We show that entropy is a measure of information lost in the passage from the classical theory of sound and vibration and SEA, its thermodynamical counterpart.

Vibrational energy distribution in plate excited with random white noise

2021 ◽  
Vol 263 (6) ◽  
pp. 965-969
Author(s):  
Tyrode Victor ◽  
Nicolas Totaro ◽  
Laurent Maxit ◽  
Alain Le Bot
Keyword(s):  
Boundary Conditions ◽  
Energy Distribution ◽  
White Noise ◽  
Numerical Simulations ◽  
Ray Tracing ◽  
Energy Analysis ◽  
Vibrational Energy ◽  
Statistical Energy Analysis ◽  
Vibrational Energy Distribution ◽  
Tracing Method

In Statistical Energy Analysis (SEA) and more generally in all statistical theories of sound and vibration, the establishment of diffuse field in subsystems is one of the most important assumption. Diffuse field is a special state of vibration for which the vibrational energy is homogeneously and isotropically distributed. For subsystems excited with a random white noise, the vibration tends to become diffuse when the number of modes is large and the damping sufficiently light. However even under these conditions, the so-called coherent backscattering enhancement (CBE) observed for certain symmetric subsystems may impede diffusivity. In this study, CBE is observed numerically and experimentally for various geometries of subsystem. Also, it is shown that asymmetric boundary conditions leads to reduce or even vanish the CBE. Theoretical and numerical simulations with the ray tracing method are provided to support the discussion.

Statistical Energy Analysis on Vibrational Energy Transmission in Hard Disk Drive Components

2013 ◽  
Author(s):  
Nopdanai Ajavakom ◽  
Pinporn Tanthanasirikul
Keyword(s):  
Energy Analysis ◽  
Vibrational Energy ◽  
Hard Disk Drives ◽  
Hard Disk ◽  
Disk Drive ◽  
Statistical Energy Analysis ◽  
Energy Transmission ◽  
Vibration Tests ◽  
Main Components ◽  
Loss Factors

One of the problems found in the 2.5-inch hard disk drives (HDD) in operation is its vibration. Aiming to find important information to help reduce the vibration transmitted to the outer shell of HDD, the parameters involving vibrational energy transmission among the main components of HDD are identified by the test-based Statistical Energy Analysis (SEA). First, the vibration tests of HDD in the idle mode are performed in order to identify the contribution of the main components; the platters and the top cover, to the overall vibration of HDD. Second, the SEA parameters including the dissipation loss factors of the components and coupling loss factors of the pairs of the components are then experimentally determined in order to calculate the vibration transmission power among the components.

scholarly journals The crossing rates, exceedance probabilities, and related statistical properties of the energy frequency response functions of a random built-up system

2019 ◽  
Vol 233 (18) ◽  
pp. 6409-6424
Author(s):  
Robin S Langley
Keyword(s):  
Computational Models ◽  
Energy Analysis ◽  
Vibrational Energy ◽  
Peak Height ◽  
Parametric Model ◽  
Statistical Properties ◽  
Statistical Energy Analysis ◽  
Response Functions ◽  
The Mean ◽  
Gaussian Orthogonal Ensemble

A method is derived for computing a number of key statistical properties of the vibrational energy of each component of a built-up system that has random properties. The energy is considered to be a random function of frequency, and the derived statistical properties include: the mean rate at which the energy crosses a specified level, the probability that the energy will exceed a specified level within a given frequency band, the mean trough-to-peak height, the rate of occurrence of peaks, and the mean quefrency (a measure of the rate of fluctuation of the energy). The analysis is based on combining statistical energy analysis with a non-parametric model of uncertainty based on the Gaussian orthogonal ensemble and avoids the use of Monte Carlo simulations or large computational models. By way of example, the method is applied to a number of coupled plate systems.

Experimental and Statistical Energy Analysis of the Structure-borne Noise in a Helicopter Cabin

2017 ◽  
Vol 10 (6) ◽  
pp. 323
Author(s):  
Raffaella Di Sante ◽  
Marcello Vanali ◽  
Elisabetta Manconi ◽  
Alessandro Perazzolo
Keyword(s):  
Energy Analysis ◽  
Statistical Energy Analysis

Power Flow and Energy Sharing between an Oscillator and a Continuous Receiver Structure

2011 ◽  
Vol 189-193 ◽  
pp. 1914-1917
Author(s):  
Lin Ji
Keyword(s):  
High Frequency ◽  
Power Flow ◽  
Energy Analysis ◽  
Statistical Energy Analysis ◽  
Coupled Subsystems ◽  
Modal Density ◽  
Vibration Problems ◽  
Energy Sharing ◽  
High Modal Density ◽  
Vibration Modeling

A key assumption of conventional Statistical Energy Analysis (SEA) theory is that, for two coupled subsystems, the transmitted power from one to another is proportional to the energy differences between the mode pairs of the two subsystems. Previous research has shown that such an assumption remains valid if each individual subsystem is of high modal density. This thus limits the successful applications of SEA theory mostly to the regime of high frequency vibration modeling. This paper argues that, under certain coupling conditions, conventional SEA can be extended to solve the mid-frequency vibration problems where systems may consist of both mode-dense and mode-spare subsystems, e.g. ribbed-plates.

scholarly journals Ergodic billiard and statistical energy analysis

Wave Motion ◽  
2019 ◽  
Vol 87 ◽  
pp. 166-178 ◽  
Author(s):  
H. Li ◽  
N. Totaro ◽  
L. Maxit ◽  
A. Le Bot
Keyword(s):  
Energy Analysis ◽  
Statistical Energy Analysis
Sign in / Sign up

Export Citation Format

Share Document