Field Balancing Mechanical Engineering Notes | EduRev

Mechanical Engineering : Field Balancing Mechanical Engineering Notes | EduRev

The document Field Balancing Mechanical Engineering Notes | EduRev is a part of Mechanical Engineering category.
All you need of Mechanical Engineering at this link: Mechanical Engineering

Field Balancing of a Rotor

  • Method of balancing a rotor is based on an extension of balancing of a thin disc during rotation
  • Following the text book "Principles of Vibration Control", one can show that for balancing of thin disc one needs to measure
  • a. amplitude (Ai ) and phase Field Balancing Mechanical Engineering Notes | EduRev of vibration
    b. the effect of adding additional mass ( Mt) to the disc for the amplitude (At) and phase (φt).
  • Accordingly, denoting      Field Balancing Mechanical Engineering Notes | EduRev    one can find the balancing mass ( mb) and it's location (rb, φb) in polar coordinates as

Field Balancing Mechanical Engineering Notes | EduRev

  • For balancing of a rotor one needs three trest runs and measure the amplitude and phase of vibration at two different locations 1 and 2.
     
  • At first, amplitudes and phases corresponding to unbalanced rotor at locations 1 and 2 denoted as  Field Balancing Mechanical Engineering Notes | EduRev    and Field Balancing Mechanical Engineering Notes | EduRev are measured.      

 

  • Next for a trial mass the  Field Balancing Mechanical Engineering Notes | EduRev same are noted. Let these be  Field Balancing Mechanical Engineering Notes | EduRev
  • Finally, in the third run, for a trial mass Field Balancing Mechanical Engineering Notes | EduRev one needs to obtain Field Balancing Mechanical Engineering Notes | EduRev
  • One can show that the balancing masses required are  Field Balancing Mechanical Engineering Notes | EduRev and Field Balancing Mechanical Engineering Notes | EduRevwhere,

Field Balancing Mechanical Engineering Notes | EduRev

where  Field Balancing Mechanical Engineering Notes | EduRev  

 

A rotor operating at a speed higher than (or close to) its first critical speed is termed as a flexible rotor since it undergoes a significant transverse deflection at this speed.

  • Unlike a rigid rotor, a flexible rotor cannot be balanced by adding two masses placed in two arbitrarily chosen planes.
     
  • The principle used for balancing a flexible rotor is entirely different from that applied in the case of a rigid rotor. The objective of attaching the balancing masses to a rigid rotor, as already stated, is to neutralize the unbalanced forces and moments.
     
  • In a flexible rotor, on the other hand, the balancing masses are attached to suitably modify the dynamic deflection characteristics of the rotor. The technique to do this is known as the modal balancing technique .
Offer running on EduRev: Apply code STAYHOME200 to get INR 200 off on our premium plan EduRev Infinity!

Related Searches

practice quizzes

,

study material

,

Exam

,

MCQs

,

Extra Questions

,

ppt

,

past year papers

,

video lectures

,

mock tests for examination

,

Free

,

Field Balancing Mechanical Engineering Notes | EduRev

,

Important questions

,

Summary

,

Viva Questions

,

Previous Year Questions with Solutions

,

Objective type Questions

,

Field Balancing Mechanical Engineering Notes | EduRev

,

Field Balancing Mechanical Engineering Notes | EduRev

,

Semester Notes

,

shortcuts and tricks

,

pdf

,

Sample Paper

;