Magnetic Linear Accelerator Questions

Click For Summary

Discussion Overview

The discussion revolves around the design and functionality of a magnetic linear accelerator, focusing on the use of switched electromagnets to accelerate ferritic stainless steel balls. Participants explore various technical concerns, including the management of back EMF, capacitor charging, and the timing of magnet activation.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant expresses a desire to reroute back EMF through a rectifier to reduce charge time for the capacitors, questioning the feasibility of using sufficiently large diodes and the potential for induced EMF causing issues.
  • Another participant suggests using separate capacitors for each stage of the accelerator to manage charge effectively.
  • A participant clarifies their intention to continuously fire the mechanism and discusses the idea of a cascade feed system for capacitors, acknowledging potential heat issues.
  • Concerns are raised about safety, particularly regarding the risk of projectiles getting stuck and causing collisions within the accelerator.
  • One participant proposes using a laser system to control the firing of the magnets and discusses the possibility of pre-magnetizing the projectiles to enhance acceleration.
  • A request is made for equations related to magnetic field strength, acceleration of metallic objects in a magnetic field, and the forces involved, indicating a need for mathematical groundwork before proceeding with the project.

Areas of Agreement / Disagreement

Participants express various technical concerns and ideas, but no consensus is reached on specific solutions or methods. The discussion remains open-ended with multiple competing views on the implementation and safety considerations.

Contextual Notes

Participants acknowledge limitations related to safety and technical feasibility, as well as the need for further mathematical analysis before proceeding with design choices.

Who May Find This Useful

Individuals interested in experimental physics, engineering design, and those exploring concepts related to magnetic acceleration and electromagnetism may find this discussion relevant.

Yankus
Messages
8
Reaction score
0
Firstly, I am sorry if I sound like a moron I only finished 1 year at university before leaving so I don't have the firmest grasp on some of this. I do have a massive facination with nuclear physics and quantum mechanics, string theory etc.

Secondly,

Im looking at building a linear accelerator (not those little one shot toys you see online) and am looking at a series of switched electro magnets to accelerate ferritic (yes magnetic) stainless steel balls. Still looking at what can be fired but the ss balls are eaiser to come by.

Concern 1,
I want to reroute the back EMF through a rectifier and back into the capacitors to reduce next cycle charge time but don't know if there are diodes large enough to handle the power output and also the size of the magnetic field may induce back EMF on the wrong side of the recifier causing a "missfire" by draing the capacitors rather than charging. is there a way to prevent EMF being induced in certain sections of the wiring?

Concer 2,
Firing (turning on and off) the magnets, the effect it would have on the next magnet in the sequence. Would it start inducing currents in the the next magnet causing a missfire, or could they be switched fast enough to avoid the EMF affecting the projectile.

Any help would be appreciated.

Thanks
Chris
 
Last edited:
Physics news on Phys.org
Next cycle charge time?
If I'm not mistaken, separate capacitors(already charged) should be used for each stage.
 
Hi pallidin,

Thanks for your reply. Let me clarify. I will be using a capacitor for each stage, but I want to be able to continouisly (yes i know its spelled wrong) fire the entire mechanism. If I can capture the back EMF and feed it into the capacitors it will reduce complete cycle charge time. So it can fire, by the time it gets to the last stage the first stage will be fully charged again.
Maybe a cascade feed system to the capacitors, but there's some technical issues around that one.
And yes I realize there will be heat issues I'm working on it.

Thanks
Chris
 
Ok, I see. Instead of a "'single shot" you want a "repeater"
Well, I'm sure it can be done within design limits, but I am not versed enough to know precisely how. Sorry I can not be of more help.

Chris, my only other thoughts are to please keep safety first and foremost in mind.
Homebuilt accelerators can be fun and instructive, but also dangerous.
Especially a repeating kind.
For example, let's say you get this thing working, but your 10th ball gets "stuck" at the end and your 11th ball slams into it. Anyway, ALWAYS look at what can go wrong and provide safety measures.

Nonetheless, happy experimenting!
 
Thanks Pallidin

I plan on using a laser system to fire each magnet and in theory it should be possible to electronically "jam" the mechanism should a ball get stuck preventing the one behind it impacting, which could lead into an interesing experiment into kinetic energy.

Another idea I had was to pre-magnetise the "ammo" and have the magnets reverse as it passes providing increased acceleration. Obviously safety is a top priority and Ill be using a non metallic barrel so there shouldn't be any issues with the barrel magnetising and sticking the balls.
 


Hiya,

Could anyone give me the equations for finding out:

Magnetic field strength
acceleration of a metallic object due to a magnetic field
the force felt by said object
and any others you think would be useful

Id like to do some math before buying anything because I have a couple of ideas on the boil
Thanks
Chris
 
Last edited:

Similar threads

  • · Replies 13 ·
Replies
13
Views
3K
  • · Replies 27 ·
Replies
27
Views
4K
  • · Replies 12 ·
Replies
12
Views
3K
  • · Replies 25 ·
Replies
25
Views
4K
Replies
4
Views
2K
  • · Replies 4 ·
Replies
4
Views
4K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 9 ·
Replies
9
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 8 ·
Replies
8
Views
9K