Why are railguns thermic and not kinetic?
- Thread starter Crimson Kaim
- Start date
Wellll.... to be honest, IIRC that ball of flame was most of the barrel of the railgun
. It's a prototype after all. But nevertheless, it's an impressive video.
Seriously - a (railgun) projectile at sufficient speed (doesn't have to be relativistic, a few 10's of km/sec will be sufficient) will vaporize at impact with anything that isn't a vacuum and transfer most of its kinetic energy as thermal energy.
If you're not afraid of some light physics: a projectile will have both energy and momentum. And the conservation laws dictate that both energy and momentum are conserved. Always. The thing here is that momentum scales with the speed of the projectile: momentum = speed * mass. And momentum has a direction. Kinetic energy, on the other hand, scales with the square of the speed: kinetic energy = speed^2 * mass. Since speed is squared here, kinetic energy does not have a direction.
For slow projectiles, momentum dominates on impact. Cinematic effects overdo it somewhat, but basically, that's why the impact pushes the target away. For faster projectiles, though, kinetic energy rises rapidly (square of the speed!), and on impact that energy has to go somewhere. If it can't go anywhere else, it'll turn into heat. Lots of heat.
One easily (especially for astronomers) observable phenomenon that shows this very nicely are 'falling stars'. The particles entering the atmosphere are (usually) small. Think grain of sand. But they're fast - a couple of dozen km/s or more. That grain of sand hitting the atmosphere immediately vaporizes and leaves a nice, visible trail of glowing gas.
Yes, ingame, I'm talking the real thing, which is why the ingame version is so confusing to me, no basis on reality at all, which is odd.
Particles in projectile transfer their kinetic energy onto target, thus producing high temperatures Rails are 100% and only 100% should be kinetic
Rails are 100% and only 100% should be kinetic Wellll.... to be honest, IIRC that ball of flame was most of the barrel of the railgun
But nevertheless, it's an impressive video.
Seriously - a (railgun) projectile at sufficient speed (doesn't have to be relativistic, a few 10's of km/sec will be sufficient) will vaporize at impact with anything that isn't a vacuum and transfer most of its kinetic energy as thermal energy.
If you're not afraid of some light physics: a projectile will have both energy and momentum. And the conservation laws dictate that both energy and momentum are conserved. Always. The thing here is that momentum scales with the speed of the projectile: momentum = speed * mass. And momentum has a direction. Kinetic energy, on the other hand, scales with the square of the speed: kinetic energy = speed^2 * mass. Since speed is squared here, kinetic energy does not have a direction.
For slow projectiles, momentum dominates on impact. Cinematic effects overdo it somewhat, but basically, that's why the impact pushes the target away. For faster projectiles, though, kinetic energy rises rapidly (square of the speed!), and on impact that energy has to go somewhere. If it can't go anywhere else, it'll turn into heat. Lots of heat.
One easily (especially for astronomers) observable phenomenon that shows this very nicely are 'falling stars'. The particles entering the atmosphere are (usually) small. Think grain of sand. But they're fast - a couple of dozen km/s or more. That grain of sand hitting the atmosphere immediately vaporizes and leaves a nice, visible trail of glowing gas.
Indeed, one of the interesting aspects of rail and Gauss weapons(they are different!) is the problem of speed of the projectile vs the friction in atmosphere, as that speed can be high enough that the projectile essentially vaporizes itself due to friction. I did some math on that years ago, working on weapon design for a game(we do actually use real world math sometimes ya know) and found that all the metals we use currently vaporize at fairly 'low' speeds, and had to switch to using a ceramic covered ferric projectile(magnets remember?) to make the projectile get more than a few centimeters beyond the barrel before it became a mist of superheated metal. And that exactly what real weapon engineers do for those weapons, ceramic casings around ferric cores, or in the case of the railgun, a ceramic casing around a non-ferric core, which allows for actual warheads on the projectile(the sabot the slug sits in has the ferric material in it, it's what rides the rails as the weapon is 'fired').
I personally prefer Gauss over rail, once you've got the timing and energy worked out, far more efficient weapon system, and you don't need to replace your barrel(those rails) every so many shots.
That's quite interesting. If anything I'd assumed PA's to do 70% thermic and 30% kinetic and Railguns to do 70% kinetic and 30% thermic.
PA's fire super heated plasma in a physical ball (as plasma can also have a physical impact due to density) so it is logical that plasma, while being both thermic/kinetic, does more thermic damage than kinetic. Whereas railguns fire a physical object (kinetic) with such force/velocity that it vaporises on impact (generating heat but not as much as a plasma ball, which is essentially as hot as a star).
All that aside, I could be persuaded to see a certain logic to railguns currently doing more thermic than kinetic. In ED the physical round railguns fire pierces through armour rather than delivering maximum stopping power - less kinetic force is felt when a round pierces a target rather than exploding on impact or within the target. It's like the difference between a sniper rifle bullet and a dumdum bullet (expanding bullet). They are both kinetic but with different characteristics. The dumdum has more stopping power because it expands upon impact to cause maximum damage inside the target whereas the sniper rifle bullet pierces through a target. In ED the railgun round pierces through the hull of a ship as well as generating a massive amount of heat upon the initial impact.
I'm no expert but that's how I would attempt to explain the current railgun damage percentages.
Railgun is just a description of how the thing works in general. It doesn't say anything about fired projectiles.
Hi Nyxi,
Until very recently this was the basis I worked on too but I have recently tested and discovered it to be ever so slightly different, at 2:1 thermic-kinetic, or 66.6% to 33.3%.
That's the TL;DR, here is the longer version:
https://forums.frontier.co.uk/showthread.php?t=240168&p=3716289#post3716289
Truesilver
Adle's Armada
www.inara.cz/wing/336
I interpret the "railgun" as firing a solid projectile (kinetic) so fast (at something like 90% of lightspeed) that the damage it does is primarily thermic, rather than the kinetic damage of traditional projectiles. The visual effect of the weapon firing matches this, as it resembles a beam rather than a cannon.
Well technically, on the molecular level, thermal damage is kinetic damage (hurr hurr hurrrrrr)
...but yeah, the railgun is a penetrator weapon, so the best way of doing that is launching a really hard projectile really fast, which makes it kinetic. The amount of energy needed for the acceleration bleeds off into thermal energy when it hits the target, so it might as well be thermal too, which is what makes it good against shields.
tl;dr you need kinetic to defeat armour, which turns into thermal when it hits, so both types I guess?
Terrible explanation, but you get the idea.
...but yeah, the railgun is a penetrator weapon, so the best way of doing that is launching a really hard projectile really fast, which makes it kinetic. The amount of energy needed for the acceleration bleeds off into thermal energy when it hits the target, so it might as well be thermal too, which is what makes it good against shields.
tl;dr you need kinetic to defeat armour, which turns into thermal when it hits, so both types I guess?
Terrible explanation, but you get the idea.
What the title says. AFAIK railguns accelerate a projectile (therefore kinetic) to a very high velocit up to 15 km/s if I am correct (atmosphere).
However, in Elite railguns are thermic weapons so they are a laser? I am confused, may someone explain this to me, please?
Thanks
https://en.wikipedia.org/wiki/Railgun
Rail-gun ammunition travels at Mach 7 (8,600 km/h), and that is rated in an atmosphere - in space, they will travel slightly faster - and in the year 3302, probably even faster than what we can do. With it being so fast, the resultant explosion will also produce LOTS of heat on contact.
Shooting a ship with rail-guns, in space, is like throwing a comet the size of your fist at ten's of thousands of km/h - same effect. When it makes contact, BOOM! Lots of heat generated from the kinetic impact.
A railgun is a kinetic weapon. It shoots a projectile and the damage is done through kinetic impact.
Lasers are thermic, accelerated (heated) plasma should do thermal damage.
Missiles are also kinetic if they are designed to accelerate and then hit the target. If they explode before, they are thermic - and rather useless as the thermal radiation is released in all directions, rather than in a single direction as in a laser.
Lasers are thermic, accelerated (heated) plasma should do thermal damage.
Missiles are also kinetic if they are designed to accelerate and then hit the target. If they explode before, they are thermic - and rather useless as the thermal radiation is released in all directions, rather than in a single direction as in a laser.
Take one lump of metal.
Stick it in a Rail Gun.
Apply lots of energy, so that melts.
Fire that ball of molten metal out of said Rail Gun.
And casually ignoring the amount of heat it would lose during transit.. or maybe some sort of latent energy surge slows that down.. pfft I dunno. Why you asking me, eh? Why? Why Should I care? Leave me alone. Go. Get away with you.. Shoo.
Stick it in a Rail Gun.
Apply lots of energy, so that melts.
Fire that ball of molten metal out of said Rail Gun.
And casually ignoring the amount of heat it would lose during transit.. or maybe some sort of latent energy surge slows that down.. pfft I dunno. Why you asking me, eh? Why? Why Should I care? Leave me alone. Go. Get away with you.. Shoo.
It's all science,
the projectiles are made of a special alloy composed of 20%phantastium, 30%imaginarium and 50%pyhsicgnorium.
the projectiles are made of a special alloy composed of 20%phantastium, 30%imaginarium and 50%pyhsicgnorium.