- #1

Skrew

- 131

- 0

You are using an out of date browser. It may not display this or other websites correctly.

You should upgrade or use an alternative browser.

You should upgrade or use an alternative browser.

- Thread starter Skrew
- Start date

- #1

Skrew

- 131

- 0

- #2

viscousflow

- 272

- 0

Where can you learn about them? Google.

- #3

AlephZero

Science Advisor

Homework Helper

- 7,025

- 297

For example, there are vibration patterns of a circular disk supported at the center, with N radial and M cirumferential nodal lines, for any integers N >= 0 and M >= 0. That's simple enough.

Now consider the vibration patterns of something like a fan with K identical blades mounted on a central hub. There are analogous sets vibration patterns, but they are not so obvious because every blade may be vibrating in a different way, for example if there are no common factors between the number of blades and the number of radial "nodal lines".

Now consider the case where these vibration patterns are rotating around the disk as travelling waves, rather than forming a "stationary" vibration pattern"

Now consider the disk is also rotatiing, but not at the same speed as the waves are rotating around it.

And finally couple several of these together one flexible rotor, with different numbers of blades in each disk...

Some general theory of to how to keep track of what is going on is quite useful here

It gets even more interesting when you make the more realistic assumption that the blades are only

- #4

Studiot

- 5,441

- 9

I suppose it kinda depends on your idea of abstract algebra, by my book includes modular arithmetic.

So in reading this on you miracle of modern engineering - your pc - you are using abstract algebra.

So in reading this on you miracle of modern engineering - your pc - you are using abstract algebra.

Last edited:

- #5

Skrew

- 131

- 0

For example, there are vibration patterns of a circular disk supported at the center, with N radial and M cirumferential nodal lines, for any integers N >= 0 and M >= 0. That's simple enough.

Now consider the vibration patterns of something like a fan with K identical blades mounted on a central hub. There are analogous sets vibration patterns, but they are not so obvious because every blade may be vibrating in a different way, for example if there are no common factors between the number of blades and the number of radial "nodal lines".

Now consider the case where these vibration patterns are rotating around the disk as travelling waves, rather than forming a "stationary" vibration pattern"

Now consider the disk is also rotatiing, but not at the same speed as the waves are rotating around it.

And finally couple several of these together one flexible rotor, with different numbers of blades in each disk...

Some general theory of to how to keep track of what is going on is quite useful here

It gets even more interesting when you make the more realistic assumption that the blades are onlyapproximatelyidentical, to within manufacturing tolerances etc.

I'm not seeing how you could model this using groups.

Mind explaining it a bit more?

- #6

radou

Homework Helper

- 3,134

- 7

In the book I'm just going through, one of the examples in the exercises is binary coding.

Share:

- Replies
- 4

- Views
- 122

- Last Post

- Replies
- 8

- Views
- 245

- Replies
- 1

- Views
- 454

- Replies
- 68

- Views
- 1K

- Last Post

- Replies
- 2

- Views
- 1K

- Replies
- 18

- Views
- 749

- Last Post

- Replies
- 32

- Views
- 2K

- Replies
- 2

- Views
- 312

- Replies
- 12

- Views
- 1K

- Replies
- 2

- Views
- 931