Seeking Expert Design Optimization Guidance

Boom! The classic potato gun harnesses the combustion of flammable vapor. Show us your combustion spud gun and discuss fuels, ratios, safety, ignition systems, tools, and more.
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jackssmirkingrevenge
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Thu Jun 29, 2023 11:21 am

Goodtimes42 wrote:
Wed Jun 28, 2023 5:47 pm
I'm making a maap gas powered cannon that will shoot 2.6" 12 oz. projectiles (soda cans) . I'm trying to figure out the optimal, most efficient barrel length. Do you know how I could figure that out? Also, I'm wondering what the optimal barrel diameter to chamber diameter ratio is. I could only find volume ratios in my searches.
There is a good simulation program called HGDT that you can download here that can help you optimize your design.
hectmarr wrote:You have to make many weapons, because this field is long and short life
Goodtimes42
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Sat Jul 01, 2023 6:41 pm

Hello Gents,

I am relatively new to this forum and I would really appreciate any guidance you guys may have regarding optimizing my design. The goal of this project is to launch soda cans (2.6" OD /weight: 13 OZ) at the greatest velocity possible. I have been using the HGDT calculator and I think I have come up with some pretty good dimensions for my build. I'm still unsure about a few aspects of the calculator so I would really appreciate it if you could take a look at the attached screen shot and or the HDT file in the zip folder and provide any possible improvement suggestions.

Aspects of calculator that I'm unsure of
- Disk Failure: This is not a hybrid design so i set the disc failure pressure to 0.
- Friction: I wasn't sure what to put in here. Can OD: 2.6" Barrel ID: 2.63"

Thank you in advance. Take care and have yourselves a great day.
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jrrdw
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Sun Jul 02, 2023 6:19 am

Topic moved to proper forum section. @Goodtimes42, you have a PM in your inbox.
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jackssmirkingrevenge
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Sun Jul 02, 2023 5:50 pm

Goodtimes42 wrote:
Sat Jul 01, 2023 6:41 pm
- Disk Failure: This is not a hybrid design so i set the disc failure pressure to 0.
This is correct, also unless you are installing a chamber fan, you can set Chamber Fan Data to zero as well.
Friction: I wasn't sure what to put in here. Can OD: 2.6" Barrel ID: 2.63"
If the can diameter is smaller than the barrel OD you can put 1

For Ign Num unless you have multiple spark gaps put 1

Otherwise it looks good!
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Moonbogg
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Mon Jul 10, 2023 9:22 pm

Any update on this?
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