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New Basic Calculator


JMan

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Hi everyone. I asked for some help here with basic rocket calculations and got some great advice. I ended up delaying my "release" to you guys as i improved the calculations with some calculus for more accurate results. I must admit that it is not incredibly accurate but I find it works good for basic sugar motors and I have even put in some estes motors and gotten close to how they actually preform (its hard to find data on their fuel such as true burn time and density so I believe that is where the bigger part of the errors come from in that).

 

Any ways, disclaimer time. This code is not to be used for how a rocket or fuel of any kind will preform or behave. This code/program is for demonstration purposes only. I am not liable for anyone else's use of this code. (if you can think of a better disclaimer that will keep me safe please let me know and I'll edit this post).

 

Some notes:

If you want to update a rocket in the database you have to his delete (note this will not remove what you put in until you select a different rocket) then hit add again.

 

This program assumes constant burn rate so you may want to make a few fuels to choose from specifiying what pressure that fuel is under (such as KNSU at 303000 pa) and have its burnrate be what ever KNSU's is at 303000. Richard Nakka and James Yawn have good graphs on pressure vs burnrate, if not guess the pressure and burn rate and make a rocket with that. If the pressure differes form what you put, just guess and check until it matches.

 

This is not a simulator, a calculator. That means there is no start up effects or anything fancy like that. Everything ignites instantly and preforms perfectly.

 

You may want to change the EXAMPLE fuels I have to start out to ones that closer fit how your fuel preforms. This will let you get more accurate results for your motors. (the numbers in there are very ideal especially the ISP's)

 

I especially like using this to see how much fuel I have to make to measure out before making my rocket. Hate when I'm 20 grams short or 50 grams too much and I waste stuff or got to make another batch.All of the numbers you see at first are procedurally generated, try them out or disregard them I don't care.

 

This is coded in MATLAB but is a .exe file. If you would like to see the actual code just ask and I'd be happy to share but the forum will not let me upload .m files

 

You may have to download a MATLAB runtime thing to get the .exe to open.

 

 

 

https://github.com/Jman0519/Rocket-Calculator

 

I tried to upload it directly to the forum but it will not let me. Anyways here the link with all of the code and the installer. If you use it please give it a review on the forum here and let me know what you think of it.

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Have you seen or tried BurmSim? www.burnsim.com. Mostly used for APCP composite propellants, but many use it for sugar as well. Geared more towards actual rockets rather than pyro, though.

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Yes gdeputy, I looked at every one I could find to make this one and tried to get the best of every program. Obviously, I couldnt code all of these things in and I would have liked to, and there are some things I could code in and I just didnt (such as nozzleless options like I have inhibitited) and just didnt find it useful to do at the moment. If there is enough want for an option I can update it for you guys but I just wanted to get your impressions.
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