# Tangential stresses in rotating ring

**URL:** <https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058>\
**Category:** Shift518 Automotive\
**Created:** [March 24, 2009, 10:28pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058 "2009-03-24T22:28:55Z")\
**Posts on this page:** 20\
**Page:** 1

<div class="post-metadata">

**Author:** ![1320-20V](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/1320-20v/32/6474_2.png) [@1320-20V](https://forums.speedlife.net/u/1320-20V)\
**Post date:** [March 24, 2009, 10:28pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/1 "2009-03-24T22:28:55Z")

</div>

(Radians per second)=(C15_C20_((3+C19)/8)_((C16^2)+(C17^2)+(((C16^2)_(C17^2))/(C18^2))-((1-(3_C19))/(3+C19))_(C18^2)))^0.5  
Discuss.

---

<div class="post-metadata">

**Author:** ![kramerbuccs24](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/kramerbuccs24/32/6397_2.png) [@kramerbuccs24](https://forums.speedlife.net/u/kramerbuccs24)\
**Post date:** [March 24, 2009, 10:40pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/2 "2009-03-24T22:40:35Z")

</div>

my head hurts

---

<div class="post-metadata">

**Author:** ![bennyfizzle](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/bennyfizzle/32/6291_2.png) [@bennyfizzle](https://forums.speedlife.net/u/bennyfizzle)\
**Post date:** [March 25, 2009, 4:23am UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/3 "2009-03-25T04:23:01Z")

</div>

I can not fucking WAIT for Math 2/3.

FUUUUUUUUUUUU

---

<div class="post-metadata">

**Author:** ![crAppAchic0](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/crappachic0/32/6306_2.png) [@crAppAchic0](https://forums.speedlife.net/u/crAppAchic0)\
**Post date:** [March 25, 2009, 8:31am UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/4 "2009-03-25T08:31:53Z")

</div>

Would it be the stress distributed over the entire ring, or a segment of the ring?

Oh, come on… someone’s gotta say something… 🙂

---

<div class="post-metadata">

**Author:** ![OsoiNA6](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/osoina6/32/6301_2.png) [@OsoiNA6](https://forums.speedlife.net/u/OsoiNA6)\
**Post date:** [March 25, 2009, 8:19pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/5 "2009-03-25T20:19:51Z")

</div>

Word of advice, go get a piece of paper and write formulas down, scan them, and then post that up so it doesn’t look like garbage and maybe someone can follow you.

Not trying to be a smart a$$ but if you can’t even be clear with the original formula how do you expect anyone to follow your work? It makes it look like you want answers but don’t have the patience to even stage the problem properly.

It would be nice too if you specified where you are calculating stress, and for what reason. Material would be a nice start too if you are trying to find out about allowables, etc.

---

<div class="post-metadata">

**Author:** ![kramerbuccs24](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/kramerbuccs24/32/6397_2.png) [@kramerbuccs24](https://forums.speedlife.net/u/kramerbuccs24)\
**Post date:** [March 25, 2009, 8:21pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/6 "2009-03-25T20:21:46Z")

</div>

fuck all of you

---

<div class="post-metadata">

**Author:** ![OsoiNA6](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/osoina6/32/6301_2.png) [@OsoiNA6](https://forums.speedlife.net/u/OsoiNA6)\
**Post date:** [March 25, 2009, 8:24pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/7 "2009-03-25T20:24:02Z")

</div>

> [@help me find wny waterfront resturaunt's](https://forums.speedlife.net/t/help-me-find-wny-waterfront-resturaunts/16190/13):
>
> fuck all of you

Yeah yeah yeah next time you go for a rip in a nice ride, enjoying the exhaust note of a high strung \_\_\_\_\_\_\_ blasting off the canyon walls, remember that engineers made it possible!! HAHAH

---

<div class="post-metadata">

**Author:** ![kramerbuccs24](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/kramerbuccs24/32/6397_2.png) [@kramerbuccs24](https://forums.speedlife.net/u/kramerbuccs24)\
**Post date:** [March 25, 2009, 8:25pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/8 "2009-03-25T20:25:21Z")

</div>

yeah well fuck you for knowing the first thing about this shit

---

<div class="post-metadata">

**Author:** ![OsoiNA6](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/osoina6/32/6301_2.png) [@OsoiNA6](https://forums.speedlife.net/u/OsoiNA6)\
**Post date:** [March 25, 2009, 8:32pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/9 "2009-03-25T20:32:36Z")

</div>

> [@NYIRP 9.29.06](https://forums.speedlife.net/t/nyirp-9-29-06/16186/7):
>
> yeah well fuck you for knowing the first thing about this shit

I don’t know $hit… I’m just trying to sound intelligent… While asking about the OP who seems to sound intelligent as well but maybe, just maybe, has no clue about this $hit either…

OK actually- I do it to feel better about myself.

It’s the thinking man’s equivalent of calling someone’s bluff at LVD knowing all you got is a stock Geo Metro on 155/80 12" snows running on two of three cylinders.

---

<div class="post-metadata">

**Author:** ![kramerbuccs24](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/kramerbuccs24/32/6397_2.png) [@kramerbuccs24](https://forums.speedlife.net/u/kramerbuccs24)\
**Post date:** [March 25, 2009, 8:37pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/10 "2009-03-25T20:37:53Z")

</div>

^ :rofl

---

<div class="post-metadata">

**Author:** ![OsoiNA6](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/osoina6/32/6301_2.png) [@OsoiNA6](https://forums.speedlife.net/u/OsoiNA6)\
**Post date:** [March 25, 2009, 8:43pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/11 "2009-03-25T20:43:42Z")

</div>

> [@help me find wny waterfront resturaunt's](https://forums.speedlife.net/t/help-me-find-wny-waterfront-resturaunts/16190/16):
>
> ^ :rofl

Seriously… Notice how I put nothing of substance in my reply, but it sounds legit.

I believe some old school rap artists refer to it as: Faking Jacks.

Except you’re on top of the situation, not the bottom.

Work on this skill man, it will come in handy like every day in your working life.

I am still plugging away trying to get it right too…

Haha.

---

<div class="post-metadata">

**Author:** ![kramerbuccs24](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/kramerbuccs24/32/6397_2.png) [@kramerbuccs24](https://forums.speedlife.net/u/kramerbuccs24)\
**Post date:** [March 25, 2009, 8:45pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/12 "2009-03-25T20:45:52Z")

</div>

all i know is that my head still hurts

kramerbuttz+math=headache.

---

<div class="post-metadata">

**Author:** ![1320-20V](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/1320-20v/32/6474_2.png) [@1320-20V](https://forums.speedlife.net/u/1320-20V)\
**Post date:** [March 25, 2009, 9:23pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/13 "2009-03-25T21:23:45Z")

</div>

> [@Callout: Ugososlow](https://forums.speedlife.net/t/callout-ugososlow/16063/22):
>
> Would it be the stress distributed over the entire ring, or a segment of the ring?
> 
> Oh, come on… someone’s gotta say something… 🙂

Lyndon! Whats up? You are the only one who “got it”

to answer your question, Im not sure. I did the math on paper, I know its right, but I know the number is not correct either.

I must be using the wrong formula, or mis-interpreting the conditions.

Tangential stress:

Radial Stress:  
  
Variables:

For my conditions:  
a=0"  
b=3.375"  
v=.30  
p=.275 lb/in^3  
r= 0" for radial  
r= 3.375" for tangential  
stress= 294,426 PSI

I am solving all formulas for Omega.

---

<div class="post-metadata">

**Author:** ![1320-20V](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/1320-20v/32/6474_2.png) [@1320-20V](https://forums.speedlife.net/u/1320-20V)\
**Post date:** [March 25, 2009, 10:35pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/14 "2009-03-25T22:35:35Z")

</div>

Found 2 mistakes! one in the formula!!! is 1+3v i had 1-3v!

also the stress is E not the ultimate. and order of magnitude difference.

---

<div class="post-metadata">

**Author:** ![OsoiNA6](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/osoina6/32/6301_2.png) [@OsoiNA6](https://forums.speedlife.net/u/OsoiNA6)\
**Post date:** [March 25, 2009, 10:37pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/15 "2009-03-25T22:37:09Z")

</div>

> [@On another topic](https://forums.speedlife.net/t/8661/764):
>
> Lyndon! Whats up? You are the only one who “got it”
> 
> to answer your question, Im not sure. I did the math on paper, I know its right, but I know the number is not correct either.
> 
> I must be using the wrong formula, or mis-interpreting the conditions.
> 
> Tangential stress:
> 
> Radial Stress:  
>   
> Variables:
> 
> For my conditions:  
> a=0"  
> b=3.375"  
> v=.30  
> p=.275 lb/in^3  
> r= 0" for radial  
> r= 3.375" for tangential  
> stress= 294,426 PSI
> 
> I am solving all formulas for Omega.

OK so you are assuming a solid disk made of mild steel (I’m assuming from your density and Poisson’s Ratio).

Tangential stress equation seems to match that for a disk of uniform thickness under rotation.

I didn’t try plugging in your numbers (and I don’t see an angular velocity in your assumptions, not sure why you are solving for it when sigma is unknown as well)…

But your result is about 7 times the yield strength of a mild steel.

So… Uh… Don’t use it on your car when driving near me. Thanks.

---

<div class="post-metadata">

**Author:** ![1320-20V](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/1320-20v/32/6474_2.png) [@1320-20V](https://forums.speedlife.net/u/1320-20V)\
**Post date:** [March 26, 2009, 12:33am UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/16 "2009-03-26T00:33:44Z")

</div>

Sigma is given, it is 29,442,600 psi.

Steel is far from mild. Actually is the strongest stainless steel in existence.

I am solving for omega.

---

<div class="post-metadata">

**Author:** ![OsoiNA6](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/osoina6/32/6301_2.png) [@OsoiNA6](https://forums.speedlife.net/u/OsoiNA6)\
**Post date:** [March 26, 2009, 6:23am UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/17 "2009-03-26T06:23:33Z")

</div>

> [@Remove tint? Can I do it?](https://forums.speedlife.net/t/remove-tint-can-i-do-it/16201/7):
>
> Sigma is given, it is 29,442,600 psi.
> 
> Steel is far from mild. Actually is the strongest stainless steel in existence.
> 
> I am solving for omega.

Thanks for the explanation… It seemed with the order of your calculation you arrived at that sigma at the bottom. I understand now that it’s part of the calculation parameters.

Are you solving for omega to find some sort of limiting angular velocity that will keep you under the allowable stress for your material?

Dunno if this will show up in the link, but the rules of thumb book for Mechanical Engineers book from Google Books has some useful formulas for the disk calculation:

> **[Rules of Thumb for Mechanical Engineers](https://books.google.com/books?id=yNHuleaCMOkC&pg=PA312&lpg=PA312&dq=tangential%2Bstress%2Bequation%2Brotating%2Bdisc&source=bl&ots=p_1C0sdlWa&sig=NPxw8hcLhu0FL9abr7vAFBSYiTY&hl=en&ei=nQ7LSfvcB9_elQeYleDMCQ&sa=X&oi=book_result&ct=result)**
>
> Save time with this collection of straightforward, common-sense techniques that provide quick, accurate solutions to your engineering problems. Rules of Thumb for Mechanical Engineers assembles hundreds of shortcuts, calculations, practical "how-to"...

See page 311 (I think the link above brings you to it)

---

<div class="post-metadata">

**Author:** ![bennyfizzle](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/bennyfizzle/32/6291_2.png) [@bennyfizzle](https://forums.speedlife.net/u/bennyfizzle)\
**Post date:** [March 26, 2009, 6:49am UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/18 "2009-03-26T06:49:03Z")

</div>

I hate you guys for having this knowledge.

Luckily I hope to be learning it within a year or two.

---

<div class="post-metadata">

**Author:** ![Jeff\_K](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/jeff_k/32/6431_2.png) [@Jeff\_K](https://forums.speedlife.net/u/Jeff_K)\
**Post date:** [March 26, 2009, 12:01pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/19 "2009-03-26T12:01:59Z")

</div>

> [@Remove tint? Can I do it?](https://forums.speedlife.net/t/remove-tint-can-i-do-it/16201/7):
>
> Sigma is given, it is 29,442,600 psi.
> 
> Steel is far from mild. Actually is the strongest stainless steel in existence.
> 
> I am solving for omega.

So is there actually a question that you had in this thread or are you just throwing up random stress calcs as you are taking classes?

---

<div class="post-metadata">

**Author:** ![OsoiNA6](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/osoina6/32/6301_2.png) [@OsoiNA6](https://forums.speedlife.net/u/OsoiNA6)\
**Post date:** [March 26, 2009, 12:53pm UTC](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058/20 "2009-03-26T12:53:02Z")

</div>

> [@VZW EVDO crew!](https://forums.speedlife.net/t/vzw-evdo-crew/16013/23):
>
> So is there actually a question that you had in this thread or are you just throwing up random stress calcs as you are taking classes?

+1… I’ve been waiting to hear an actual question instead of just random formulas so there is something clear to work with.

No explanation of objective / material / assumptions, just BAM a formula and people are supposed to figure it out!?

[Next page](https://forums.speedlife.net/t/tangential-stresses-in-rotating-ring/243058.md?page=2)
