1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Mechanics: Eccentric torsion + non circular tube

  1. Nov 4, 2008 #1
    dear all, i have just received a question about torsion.

    1. The problem statement, all variables and given/known data
    *************** a graph has been attached as attachment at bottom*************

    The objective is to find the torsion shear stress at the cross section of the "dark Grey tube".

    Let's have a look:
    1.There is a reaction torque acting on the motor M,
    2.The force is then transfered to dark grey tube by a light grey carrier.
    3. blue cross is the center of the motor
    4. purple cross is the centroid of the dark grey tube
    5. i have J / Ixx,Iyy of that tube
    6. Only the dark grey tube is fixed at 2 ends.
    7. carrier is mush shorter than the tube

    2. Relevant equations

    I think I am finding the suitable eqts. So I miss this section.
    You think T/J= shear/R ??

    3. The attempt at a solution

    #1 i would like to ask whether the following steps are correct
    #2 What is the torsion equations for irregular hollow section.
    #3 how to find the R, outer radius of the shaft, for the case that equation T/J= shear/R is used.

    My Methodology:
    1. Shear force is acting at the 2 hand sides of the tube as resultant.
    2. the Shear force acts like a torque on the hollow section
    3. use parallel axis theorem to transform "moment of inertia" from the original centroid to the torque center
    4. use a torsion equation that contain J to fix it (<------------#2 that's what i would like to find now)

    Thank you very much for your help.

    Attached Files:

    Last edited: Nov 4, 2008
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you help with the solution or looking for help too?

Similar Discussions: Mechanics: Eccentric torsion + non circular tube