(adsbygoogle = window.adsbygoogle || []).push({}); Stress' in rotating discs. HELP!!

I am working on an independent project where I am analyzing the maximum possible angular velocity of a solid disc of a given diameter and material.

The Diameter is 6.75"

Material is 440c

E= 29,000 Ksi

Density of .275lb/in^3

Ultimate tensile strength: 294,426 Psi (294Ksi)

How fast can this rotate?

Part2:

How do I quantify the stress concentration of RADIAL holes in this disc? I have found numerous papers on eccentric holes but not radial on the periphery. Holes are blind and tapped.

Maximum speed should be around 40K-60K RPM.

I have been using these formulas:

https://www.physicsforums.com/latex_images/14/1425557-0.png [Broken]

https://www.physicsforums.com/latex_images/14/1425557-1.png [Broken]

I have taken R to be zero for radial stress (the center)

and 3.375 for tangential stress.

I originally used the ultimate stress and solved for omega, but those results were 10x lower than realistic.

So i used E, and the results seem reasonable. Although I am not sure WHY I had to use E or if this was the right thing to do.

Can I get some assistance? Thanks.

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# Stress' in rotating discs. HELP

**Physics Forums | Science Articles, Homework Help, Discussion**