Calculating Deflection in Ring Fixed at Center with Point Force

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vishal007win
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How to calculate the deflection in ring, fixed at center, with a radial point force acting at some point(let say at theta=0) ?
I have derived complete set of equations. Now how to apply boundary conditions ?
to get a complete solution of 4th order equation, I need 4 B.C's, but here displacements are not specified at any point. Imposing periodicity I can get 2 more conditions
u(0)=u(2*pi)
w(0)=w(2*pi)
where u and w are radial and tangential displacements respectively
and how to apply force boundary condition in this case?

Can someone please help?
 
How to calculate the deflection in ring, fixed at center, with a radial point force acting at some point(let say at theta=0) ?

This does not make sense.

A ring has no material centre, do you mean a disk?

Perhaps a diagram?
 
consider the thin ring on elastic foundation(shaded portion shown in the figure is an elastic foundation(elastic membrane) which provide a support from center to ring)
The inner circle shown can be taken as mass-less and inertia-less disc.
actually resembling the tyre geometry with side walls and inner wheel drum.
now if a point load is applied at the circumference of ring. How to calculate the static deflection in this case?
 
Attachments
  • Diagram of a rotating ring on an elastic foundation: a thin outer ring surrounds a hatched annular elastic layer, with a small inner circle at the centre, radius a, polar angle theta, and labelled u_theta, u_3 and h.
    Untitled.jpg
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If h is your applied load, and the wheel does not touch the ground I still don't see equilibrium in your diagram.

How is the elastic centre supported?
 
Studiot said:
If h is your applied load, and the wheel does not touch the ground I still don't see equilibrium in your diagram.

How is the elastic centre supported?
h is the width of the ring.
the attachment in the above post actually resembles kind of set up shown in the figure below.. where elastic membrane resembles the sidewalls of tires and the ring represents the belt of tire and the inner disc represents the wheel drum. Now equilibrium is maintained by the reaction from the centre which is fixed(force getting transmitted by elastic membrane). i hope that makes the problem clear.
now instead of modelling contact region, if radial point force is applied at bottom, assuming the centre of wheel fixed, how to find the static deflection of ring?
 
Attachments
  • Photo of an aircraft tailwheel or nose wheel assembly with a small black tire marked AERO CLASSIC, mounted on a silver steering fork and axle arm, on a dark surface.
    tailwhl1.jpg
    54 KB · Views: 668