Go Back   Physics Help Forum > High School and Pre-University Physics Help > Electricity and Magnetism

Electricity and Magnetism Electricity and Magnetism Physics Help Forum

Reply
 
LinkBack Thread Tools Display Modes
Old Dec 18th 2011, 11:44 AM   #1
Junior Member
 
Join Date: Dec 2011
Posts: 3
Railgun Math Simulator

Hey all
Im a second year engineering student bored as hell in the second week of a 3 month vacation. So i decided to try and build a small railgun capable of launching a projectile(20-40g) to about 400km/h.

Attached is a excel file. It is a sort of simulation.

Cells in Blue must be typed in by user.
Cells in Green list the Current/Mass needed to achieve desired values.
The Cell in red must get its values from the table at a given point ( you choose )


This all makes alot more sense with the simulator.
Please try it out! Any suggestions are welcome! Point out all the mistakes i made ( there must be a few ) and be critical please. This is a dangerous undertaking and i want to be as sure as possible about the math.

Thank You!
Attached Files
File Type: xls Railgun.xls (68.0 KB, 40 views)
Fr1ki is offline   Reply With Quote
Old Dec 21st 2011, 08:00 AM   #2
Physics Team
 
ChipB's Avatar
 
Join Date: Jun 2010
Location: Morristown, NJ USA
Posts: 2,299
Quite ambitious. Looks like you'll need a power supply of about 4 megawatts to reach your goal (volts x amps), able to deliver about 50,000 joules of energy (volts x amps x time).
ChipB is offline   Reply With Quote
Old Dec 22nd 2011, 03:21 AM   #3
Junior Member
 
Join Date: Dec 2011
Posts: 3
Yes i know it is quite ambitious, but do think it is possible? does the simulator 'simulate' accurately? i was thinking about 6 capacitors would do the job? Each of them about 6800uF and 450V in parallel. I'm currently studying chemical engineering, and I thus do not have the necessary textbooks to supply me with answers. If you think it not possible, what weight and speed do you think i can achieve?
Thanks for replying.

Last edited by Fr1ki; Dec 22nd 2011 at 03:25 AM.
Fr1ki is offline   Reply With Quote
Old Dec 22nd 2011, 06:35 AM   #4
Physics Team
 
ChipB's Avatar
 
Join Date: Jun 2010
Location: Morristown, NJ USA
Posts: 2,299
Might be possible, but incredibly risky. You're talking lethal amounts of current and energy, so this is not something to do on a whim. Finding capacitors of the size you need and rated for > 450 violts is a bit tricky - I found one from a supplier like in the attached picture. Note they are about $1000 each and require a signed safety affidavit! And getting 10,000 amps to the device will require massive cables - I don't know how you would connect them. I suspect that superconducting cables would be the only practical way - and now you're really talking big $$!
Attached Thumbnails
Railgun Math Simulator-capacitor.jpg  
ChipB is offline   Reply With Quote
Old Jan 3rd 2012, 11:19 PM   #5
Junior Member
 
Join Date: Dec 2011
Posts: 3
I was searching around the web alot and talking with various engineers where I am doing vacation work, and all of them say that I do not need large cables at all. They say that the current pulse is so quick, that it will hardly even warm up a thin wire. But the longer the pulse needed, the thicker the wire has to be. Which kind of makes sense to me.
And, I have been searching around, and I will go with a 220V capacitor bank. The reason for this is that it is WAY cheaper ($20-$50 each), and, in my country, we use 220V outlets. So I will charge them with a diesel generator. Or that is the idea at least.

So the paramenters of the simulator has changed a bit. I will only require about 5500 amps but I must use a 12g projectile.
Fr1ki is offline   Reply With Quote
Reply

  Physics Help Forum > High School and Pre-University Physics Help > Electricity and Magnetism

Tags
math, railgun, simulator



Thread Tools
Display Modes


Similar Physics Forum Discussions
Thread Thread Starter Forum Replies Last Post
PhD in Math or in Math Education? ilovemath General Physics 1 Feb 8th 2013 01:03 PM
Simulator jaiii Physics Software 0 Mar 7th 2011 12:27 AM
Is my Math ok? Singularitarian Quantum Physics 8 Nov 24th 2009 10:06 PM
What math inbetween? AniMuS Thermodynamics and Fluid Mechanics 0 Jul 7th 2009 05:02 AM
math Tabassum Kinematics and Dynamics 2 Jan 30th 2009 11:30 PM


Facebook Twitter Google+ RSS Feed