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EVBEC, a combustion "simulation" spreadsheet

Posted: Mon Jan 09, 2006 6:23 pm
by boilingleadbath
EVBEC stands for Energy & Volume Based Estimator for Combustions.
It is based on <a href="www.burntlatke.com">latke's</a> chamber:barrel test data.

As of Jan 7th, 2007, it can be used to model hybrids too.

We have a <a href="http://www.spudfiles.com/spud_wiki/inde ... pudwiki</a> artical on it, and I've written a pretty detailed use guide that can be veiwed <a href="http://www.spudfiles.com/forums/viewtop ... &">here</a>.

Posted: Tue Jan 10, 2006 12:01 am
by clide
You mean something like this?

Posted: Tue Jan 10, 2006 4:44 pm
by boilingleadbath
Yeah, exactly like that!

Posted: Tue Jan 10, 2006 5:15 pm
by clide
Well looks like jimmy did something similar and sent it to you. If his isn't what you want then I can send you what I did.

Posted: Tue Jan 10, 2006 5:34 pm
by boilingleadbath
...yeah, he did what i wanted. I'v updated and changed the designation to version 1.1

Posted: Fri Nov 17, 2006 11:39 pm
by boilingleadbath
Version 1.3 has been released.
The innards are the same as they where in version 1.2... but the graph is more useful, and there's a "projectile info" calculator which will give you muzzle energy and velocity in m/s.

Posted: Sun Jan 07, 2007 1:36 am
by boilingleadbath
EVBEC version 1.4 has been released!

EVBEC v 1.4 (or as I've been mispelling it recently, EVBECH) supports differing exterior and interior pressures...
Essentialy, it allows the estimation of preformance of hybrid spudguns and spudguns being fired from on top of mountains (or with evacuated bores).

Posted: Sun Jan 07, 2007 3:03 am
by MrCrowley
3 posts in a row :shock: ...edit your post next time :wink:

never thought I would see that from you..... :P

Anyway why does it esitmate performance of spudguns on top of mountains? And can this be used with combustions or is it strictly hybrid or is it more GGDT like and if you know your stuff you could get a rough estimation?

Posted: Sun Jan 07, 2007 3:21 am
by boilingleadbath
I've been leaving my old posts alone (and they are indeed very old - some of those 3 you mentioned being posted nearly a year ago) as a kind of running history of EVBEC.

Anyways, EVBEC is design explicatly for the modling of normal combustions and hybrid cannons - no involved trickery is needed to get reasonable results like with the GGDT.
I'm not sure exactly how accurate it is, though, but I'd wager it's within 15% (velocity) a pretty large portion of the time. (yeah, I know... not that impressive. Whatever.)

As to the firing from the top of mountains - that's just an amusing way of saying that it can account for differing atmopheric pressures.
This is more practical than it appears at first glance - it allows the modling of, for instance, evacuated bores. (which, it turns out, can significantly increase muzzle energy)
On the less practical side, it also lets you predict how your hybrid (or normal spudgun) spudgun would preform in space or in a diving bell.

Oh, and I lay claim to the word "lowbrid" to describe a combustion cannon operating at a fractional mix. (like .5x)
(no, I don't claim to know why one would do this... but it's possible and makes cool looking preformance curves...)

Posted: Sun Jan 07, 2007 4:05 am
by MrCrowley
I was joking about the posts things,anyway might try your program to scale my old combustion and see what data it gives me. Can it tell you maximum range?

Posted: Sun Jan 07, 2007 10:14 am
by Bluetooth
Psssssss... You can figure that from hang time and fps.

Posted: Sun Feb 11, 2007 6:35 pm
by boilingleadbath
Well, I've released EVBEC 1.5.

It now accounts for... gas flows!

The modling techniques are somewhat speculative, but I think they should be fairly close, assuming I didnt't make any typos or something...

Posted: Sun Feb 11, 2007 9:56 pm
by boilingleadbath
...this post is temporary hosting for my EVBEC live page.

Posted: Fri Jul 06, 2007 6:29 pm
by Gepard
Sorry about kicking up an old thread - but I noticed it was linked to from the Wiki.

Can anyone tell me how accurate this is? Should I read much into the results it produces? And if not is there a better combustion calc?

Cheers,

Michael

Posted: Fri Jul 06, 2007 6:40 pm
by Fnord
Combustions are fairly random by nature, but evbec will give you ball park numbers. It gave numbers within 10% of my guns performance.