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GGDT issues

Posted: Mon Aug 06, 2007 8:55 am
by flamerz14
When the outer diameter(chamber section) is increased but the inner diameter does not change, how come the volume increases?

Posted: Mon Aug 06, 2007 9:05 am
by spud yeti
Yeah, I also noticed that, and wondered. Interestingly enough, if you maintain a constant inner diameter, but increase the outer diameter, recording the results all the time; then increase the outer and inner diameter, you will notice that the constant inner diameter's results are higher.

Posted: Mon Aug 06, 2007 9:14 am
by jimmy101
Read the instructions and help files for GGDT at http://www.thehalls-in-bfe.com/GGDT/

Posted: Mon Aug 06, 2007 2:08 pm
by DYI
The only reason for using the inner diameter function is if you are modeling a coaxial. The "outer diameter" means the inner diameter of the chamber pipe, and the "inner diameter" means the outer diameter of any pipe that is running through the inside of the chamber.

@Spudyeti: Did you actually do that, or is that just sarcasm?

Re: GGDT issues

Posted: Mon Aug 06, 2007 2:39 pm
by joannaardway
flamerz14 wrote:When the outer diameter(chamber section) is increased but the inner diameter does not change, how come the volume increases?
Because outer diameter does not refer to the outer diameter of the chamber pipe.
It refers to the INNER diameter of the OUTER pipe of your chamber..

Inner diameter refers to the OUTER diameter of any pipe running through your chamber (as in a co-axial).

Most of the time, inner diameter should be zero, and outer diameter should be the number changed.
Pretty confusing, but logical when you get used to it.

Posted: Tue Aug 07, 2007 4:27 am
by flamerz14
:shock: confusion...so if i'm building a generic spudgun am i still supposed to put in the inner diameter?

Posted: Tue Aug 07, 2007 4:42 am
by spanerman
no, unless its a coax

Posted: Tue Aug 07, 2007 11:45 am
by Modderxtrordanare
flamerz14 wrote::shock: confusion...so if i'm building a generic spudgun am i still supposed to put in the inner diameter?
Unless there is another pipe running through the inside of your air chamber (coaxial) then you need to leave inner diameter at 0 and change outer diameter according to your pipe's Inner diameter.

Posted: Tue Aug 07, 2007 3:49 pm
by boilingleadbath
D-Halls explains this just about as well as it can be explained, IMO.

However, you guys seem to be reluctant to read what other people have already written, thus requiring us to waste our time spoon feeding you.

Anyways:

The chamber dimensions describe the dimensions of the air cavity, not the pipe. The "outside diameter", thusly, describes the outside of the air cavity - which, incidentally, corresponds to inside of the pipe.

Likewise, the "inside diameter" describes a void, a hole, inside the aforementioned air cavity - the size of the hole created by "something" other than air stuck into it.