×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Gyroscopic forces

Gyroscopic forces

Gyroscopic forces

(OP)
I have a calculation problem I need some help with. I have a cooler fan which is rotating with a speed of 1000 rpm, the axis of rotation is horizontal. The whole cooler is also rotating with a speed of 1 rpm around a vertical axis. The fan is supported on one end only. I need to calculate gyroscopic forces on the bearing/axle, I suspect it is quite simple, but I have never done such a calculation before. Anyone who has? :)

Distance fan-bearing: 0,1 m
Moment of intertia, fan: 0,639 kgm2

RE: Gyroscopic forces

Double posting makes it harder to answer, and find answers. Looks like a recent post in "Bearing design......."

RE: Gyroscopic forces

(OP)
You are right. After first writing the post in "bearing design", I copied to this forum since I thought it was more suitable. My plan was to delete the first post after copying it, but I couldn't find out how to do it. Can it be done?

RE: Gyroscopic forces

1) Is this a school assignment?
2) Did you do a Google (or other Internet search engine) search on the words "gyroscopic force formula?"
3) Did you know that if you had done #2, you would have had your answer several hours ago and you wouldn't have bothered posting here, much less posting twice.
4) Hint, does the moment of inertia times the angualar momentum ring a bell?

RE: Gyroscopic forces

Ty=Iw*d(Theta)/dt
gyroscopic torque about y axis
Now equate this to external torques including gravityinduced.
From equilibrium equation
Ty+bearing torque +mgx=0
you get your answer.


I moment of inertia of spinning assembly
w = angular velocity of fan
d(theta)/dt rate of precession rotation about z axis
Ty gyroscopic torque
x distance CM to bearings
mgx moment due to gravity

RE: Gyroscopic forces

And in answer to your final question, yes: Red flag your own post and explain that you put it in the wrong forum in the box that comes up. Management will delete the offending item without holding it against you.

A.

RE: Gyroscopic forces

zeusfaber,

FYI, it was I who redflagged my own post since I had no way of deleting it.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources