A working model of a electromagnetic mass accelerator of high power / Electromagnetic Projectile Accelerators / Forums

Forums

4hv.org :: Forums :: Electromagnetic Projectile Accelerators

Next topic »

A working model of a electromagnetic mass accelerator of high power

first previous 3 4 5 6 next last

Move Thread

LAN_403

DerAlbi

Mon Dec 10 2018, 08:30PM

Registered Member #2906 Joined: Sun Jun 06 2010, 02:20AM
Location: Dresden, Germany
Posts: 727

Holy shit

sorry

I really thought this was from our emails. I am so messed up.

I was angry because you wasted my time without having done accurate measurements before opening your mouth everywhere.
I formulated this part in an email, but decided to make it a part of the debunking for all to see because you were rude to Zuckerstange.
Your last email made it clear that you judge projectile energy based on impulse.

_Eugen_

Mon Dec 10 2018, 09:10PM

Registered Member #57984 Joined: Thu Nov 19 2015, 09:44AM
Location:
Posts: 58

Funny "sratch".

To V2006:

Sulaiman Ballistic pendulum with such energy it is dangerous to try

klugesmith good idea. But I have no money for such experiences right now.

I can be a little mistaken - you did not send the device for measuring speed

Actually there is no need in any device at all to distinguish such a difference in velocity.
You should only fire vertically and measure a time t when a projectile fall down.
Initial velocity will be simply g*t/2 (where g = 9,8).
Hope you would not claim old man Newton to be wrong :)

My accelerator layout can be significantly improved in the same dimensions.
There is still room for two - three capacitors 10 000 microfarads, 450 volts.

for the money that you spend, I would do even better

(from neighbouring thread)

etc

Your cannon is rather powerful and contains as many caps as ten of smaller coilguns of other gaussbuilders, so you could use it as source of materials you need so much. But what are you plannning to improve? More condensed energy will turn your 50kg device to wall-breaking cannon moved by wheels and four horses.

V2006

Tue Dec 11 2018, 08:05AM

Registered Member #61550 Joined: Thu Apr 06 2017, 03:23PM
Location:
Posts: 86

_Eugen_: This is a good and objective way.
Launching shells vertically up I measured the speed of less powerful coils.
Launch a projectile vertically up from this powerful coil is not yet possible.
I could also launch a shell at a 45 degree angle to the horizon. And measure the distance of his flight. But nowhere to do it.
I have no money for refueling cars for long journeys.

If this model of accelerator will be supplemented by three or four capacitors, its weight will not change.
It also has a second coil. This second coil is not needed at all. A second coil was installed to compare characteristics. The weight of the second coil with fasteners is 5 - 6 kg, 5-6 kilogram is the weight of several capacitors 10,000 microfarads 450 Volts.
There will be only a destroyer of walls. In the same dimensions. Without wheels and four horses.

*In this, running vertically up complicates the situation. For example, it was noted that with a fixed accelerator, its performance is reduced to 10% of kinetic energy (depending on the degree of fixation). Surprisingly, the projectile energy is much higher if the accelerator has the ability to roll back!

DerAlbi

Tue Dec 11 2018, 11:42AM

Registered Member #2906 Joined: Sun Jun 06 2010, 02:20AM
Location: Dresden, Germany
Posts: 727

Where do you come up with those bullshit numbers like "10%" if you cant measure correctly neither horizontal nor vertical??
Your acceleration is between 530G (for 380g) or 450G (for 450g). So shooting vertical instead of horizontal is a difference around 0.2%.
Have you thought of the fact that changing your measurement method changes the measured value more than the real value changes?
Use your microphone. It is precise enough and consistent. You can use it anywhere with no problem.

If anything, fixing the accelerator should increase performance. The energy spent to push the device backwards becomes smaller the less movement is done.
At this point i simply guess, that without the accelerators movement, the shot just felt less loud, so it must be less projectile energy.. right?

V2006

Tue Dec 11 2018, 01:20PM

Registered Member #61550 Joined: Thu Apr 06 2017, 03:23PM
Location:
Posts: 86

DerAlbi: Nein.
10% of the energy is perfectly visible in the depth of penetration of the projectile into the ballistic clay.
For me, it was also surprising to see it (the fact that the rollback improves the performance of the electromagnetic mass accelerator)

DerAlbi

Tue Dec 11 2018, 01:46PM

Registered Member #2906 Joined: Sun Jun 06 2010, 02:20AM
Location: Dresden, Germany
Posts: 727

The acceleration takes place in 10ms.
If your gun weighs 50kg, and the projectile 380g, then with 40ms exit velocity, a frictionless floating coilgun would move backward with a velocity of 0.34m/s (impulse conservation). During the relevant 10ms this is only a 3mm shift. In reality this is even less, because this assumes constant velocity and no acceleration (and as said, neglecting friction).
It is very likely that the gun-movement during the relevant acceleration time is less than 1mm. Basically less than the precision you can find the initial position.

Impact depth is not a relieable measurement and ideally only represents the densitiy differences between projectile and target.
Try to translate:

Fluctuation in penetration come from various factors. Where you hit the target for example - The gun changes recoil, so it is impossible to hit the same place on target.

V2006

Tue Dec 11 2018, 02:09PM

Registered Member #61550 Joined: Thu Apr 06 2017, 03:23PM
Location:
Posts: 86

This is another confirmation that your calculations are not true.
Projectile speed in the range from 62 to 90 meters per second.
I myself could not believe my eyes when I saw that the fastening of the accelerator impairs its operation.
Before launching the projectile at the door, I conducted 20 experiments with ballistic clay. With shells of various weights - from 380 grams to 550 grams.
I even made a special emphasis for braking the accelerator against the wall.
And I was surprised to see that the rollback is very necessary.
This effect is discovered thanks to you. I wanted to make the most effective launch.
I already have some explanation for this effect.
Perhaps not the best. But there is. Rollback accelerator improves its performance! Incredible.

TechNerd

Tue Dec 11 2018, 02:34PM

Registered Member #2289 Joined: Thu Aug 13 2009, 02:49PM
Location: Jylland, Denmark
Posts: 19

I should have made a bucket of popcorn...!

DerAlbi

Tue Dec 11 2018, 03:23PM

Registered Member #2906 Joined: Sun Jun 06 2010, 02:20AM
Location: Dresden, Germany
Posts: 727

So... you are recognizing a difference of +10% energy (=110%).
Energy = m/2 * v^2.

This means you observe a velocity (and impulse-) increase of 4.8%.
4.8% of your 62 - 90m/s is 2.88 - 4.32m/s.

So you are recognizing a change of around 3m/s with absolute confidence while you are actually unsure if it is 60m/s or 90m/s while it is actually just 40m/s?
Did i summarize correctly?

Must be my math, that is again flawed.

V2006

Tue Dec 11 2018, 03:41PM

Registered Member #61550 Joined: Thu Apr 06 2017, 03:23PM
Location:
Posts: 86

fur DrAlbi: Nein.
I do not speak now about the speed range.

I am now talking about the fact that the possibility of a rollback increases the performance of an electromagnetic accelerator by 10%.
This is clearly seen from the depth of penetration of projectiles into ballistic clay â€” in the course of a great many experiments.
Video while I can not provide.

first previous 3 4 5 6 next last

Moderator(s): Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Dave Billington, Bjørn, Steve Conner, Wolfram, Kizmo, Mads Barnkob