Issues with the GGDT software

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Luke31
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Wed Mar 17, 2021 11:41 am

I am trying to use the GGDT software but im having issues. I keep getting an error stating that the projectile never cleared the barrel, but I believe I put in reasonable numbers.

The odd thing is if I increase the chamber inner diameter, it decreases the volume. If I increase the outer diameter, it increases the volume. I don't know why the outer diameter is even relevant to the experiment since its just the wall thickness.

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jackssmirkingrevenge
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Wed Mar 17, 2021 12:12 pm

"Outer Diam" is the inner diameter of your chamber tube.

"Inner Diam" is the outer diameter of your barrel for a coaxial cannon.

If your design is not a coaxial, the "Inner Diam" should be zero.
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Luke31
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Wed Mar 17, 2021 2:18 pm

jackssmirkingrevenge wrote:
Wed Mar 17, 2021 12:12 pm
"Outer Diam" is the inner diameter of your chamber tube.

"Inner Diam" is the outer diameter of your barrel for a coaxial cannon.

If your design is not a coaxial, the "Inner Diam" should be zero.
Man how were we supposed to know that. Anyway I'm starting to get realistic numbers now. Thanks!
Luke31
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Tue May 11, 2021 12:56 pm

Could someone explain the valve settings? My air cannon uses a 1'' ball valve, but I don't see any options in the settings for that.

What is..

Seat Diam
Chmber Seal
Generic valve
Barrel Seal
Hammer

How am I supposed to know the friction psi of my projectile. Anyway to test that?

Is psig the same as psi? Is it safe to assume 100 psi would equal 100 psig?
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