Mechanical Vibrations Notes

MEEM 3700 Mechanical Vibrations
Mohan Rao Chuck Van Karsen
Mechanical Engineering-Engineering Mechanics Michigan Technological University
Copyright 2003

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Lecture 1-Introduction

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No Forces No Motion

Forces

Motion

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Force Linear Non-Linear Arbitrary motion Harmonic Motion Motion

Mechanical Vibrations Sound (Acoustics)
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Dynamics and Kinematics (MEEM 2700) Strength of Materials (MEEM 2150) Thermodynamics (MEEM 2200) Differential Equations (MA3521)

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Our heart beat, our lungs oscillate, we hear because our ear drum vibrates… Vibration even makes us snore!! The light waves which permit us to see & sound waves through which we hear entail vibration We cannot even say “Vibration” without vibration of larynges, vocal cord We move by oscillating our legs We limit out discussion to “MECHANICAL VIBRATION”… i.e. Vibration of Dynamic Systems What is a Dynamic System??? Any System that contain Mass and Elasticity.

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Friend
•Conveyors, Hoppers, Compactors, Pneumatic Drills, etc. •Opening of a cork from a wine bottle •Washing Machine •Mechanical Shakers, Mixers, Sieves, Sorters, etc. •Musical Instruments •Clocks, Watches •Medical Field – Massagers, etc.

Foe
•RESONANCE – RESONANCE – RESONANCE

Tacoma Narrows Bridge

•Similar problems in machine tools, vehicles, turbines, pumps, compressors, buildings, aircraft & spacecraft systems •Excessive vibration leads to loosening on parts, noise & eventual failure •Effects of vibration on human body: Discomfort, Fatigue, Loss of Efficiency •Sound quality in products MEEM 3700 6

Lecture 1-Introduction

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Vibrations in Machinery

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Vibrations in Recreation

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Vibrations in Defense

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