Realistic and strategic mod: Ice Armor

[DiGuru]

When you take a laser chamber of, say 1 MJ, you can make that into an continious laser or a pulse laser. Depending on the maximum amount of power that chamber can handle and how you cool it, the pulse laser will probably output less energy.

A very good laser has an efficiency of about 1%. So, if you take the other direction and had a power supply that could deliver 100 MJ, what laser would do more damage over time: a continious laser or a pulse laser?

That pulse laser would pack a severe whallop, as it would deliver, say 10 MJ in about a nanosecond!!! But it would only do that every 10 seconds.

The continious laser would do exactly the same damage in the same time.

As we follow your example, the pulse laser would be 10 orders of magnitude more powerfull than the other one, as it does the damage the continious laser does in one trillionth of a second. That is not correct. They're both as powerful.

And the pulse laser only fires once every 10 seconds. If you calculate all damage per second without calculating refire rate, a one-shot weapon would always be more powerful than a weapon that is just as powerful, but has a refire rate of less than one second.

Edit: corrected a small mistake.

[mkruer]

When you take a laser chamber of, say 1 MJ, you can make that into an continious laser or a pulse laser. Depending on the maximum amount of power that chamber can handle and how you cool it, the pulse laser will probably output less energy.

A very good laser has an efficiency of about 1%. So, if you take the other direction and had a power supply that could deliver 100 MJ, what laser would do more damage over time: a continious laser or a pulse laser?

That pulse laser would pack a severe whallop, as it would deliver, say 10 MJ in about a nanosecond!!! But it would only do that every 10 seconds.

The continious laser would do exactly the same damage in the same time.

As we follow your example, the pulse laser would be 10 orders of magnitude more powerfull than the other one, as it does the damage the continious laser does in one trillionth of the same time. That is not correct. They're both as powerful.

And the pulse laser only fires once every 10 seconds. If you calculate all damage per second without calculating refire rate, a one-shot weapon would always be more powerful than a weapon that is just as powerful, but has a refire rate of less than one second.

Diguru makes a good point, but there is another aspect. All material has some resistance to change, i.e. when cutting with a laser it is always easier to continue cutting then it is to stop and start. Just the sure fact that material has a chance to cool would require additional power to start cutting again. This is partly the reason why armor is rated in different levels. Each level requires the equal or higher level damage before the material will start to give, i.e. be damage.

[etheral walker]

this problem call another problem: in space there is no way to dissipate the heat generated by a laser (hit or shoot)
We will then need a sort of cooling system

[DiGuru]

A nucleair bomb delivers a massive amount of energy in a very short time, but if you let that same bomb pump a laser, it will be MUCH more effective. That laser only delivers a fraction of the energy (say 0.01 percent or less), but it delivers it at a tiny spot, while the bomb delivers it's energy all around.

So, if you want to rate armors, you have to look at the watts per square inch.

And it doesn't stop there. For example, a laser delivers that energy to a tiny spot, but it has little penetration. The vapor it creates will diffuse and absorb most of the energy after the initial impact.

A projectile is very much slower and covers a larger area, but it has great penetration. An armor that protects against lasers will probably shatter when hit by a projectile. And an armor that protects against projectiles, will probably melt and/or explode when hit by a laser.

It might be best to rate armor with two different values: Watts/square inch for energy weapons and Watts/square inch for projectiles.

A nucleair bomb is mostly an energy weapon, except when it generates a lot of shrapnell.

[DiGuru]

this problem call another problem: in space there is no way to dissipate the heat generated by a laser (hit or shoot)
We will then need a sort of cooling system

A thick layer of ice would explode on impact into vapor, thereby absorbing the energy. And the vapor would protect against the next hit (before it dissipiates, of course).

[FlyingAce]

I think he means the heat generated by the attacking ship firing the laser

[etheral walker]

flyingace is in the truth. I was thinking of a system like in mechwarriors

[DiGuru]

To disperse heat, I think the best things you can do is to embed superconductors in the hull and all things that generate heat. That way, everything will heat up a bit and the hull will radiate it away slowly.

Cooling vanes are a lot less efficient in space, but they would work. They just have to be really big.

The best way to get rid of power and heat would probably be your engine, if you use an accelerator.

[mkruer]

OK I did some research into Ice vs Steel. As I knew, Ice is a very lousy conductor of energy, i.e. heat. Looking more detailed into Thermal conductivity vs Density. I have found facts why ice shield would be the worse type of shield you could have.

The Data
Thermal conductivity (W/[m•K]) How quickly it can dissipate heat; Density (i.e. weight per volume)

silver 422 W/mK; 10.50 Density
copper 402 W/mK; 9.0 Density
gold 298 W/mK; 19.30 Density
aluminium 226 W/mK; 2.70 Density
steel 73.3 W/mK; 7.8 Density
lead 34.8 W/mK; 11.4 Density
Water 0.61 W/mK; 1.0 Density

So in the end its not that an ice shield would not work, it’s just that it is impractical.
Pound for pound steel and other elements offer much better protection then an ice shield.
The ice shield also has 2 other what I would consider flaws. First when a laser hits the ice, the ice would instantly turn into a gas, this change would cause rapid expansion of the surrounding environment, so in essence it would be like having a bomb going off right on the surface of the hull. Also have has very little tensile strength compared to other elements, what this means is that with a single hit a much large chunk of ice shield would just flake off the ship the then spot it was impacted on.

Ideally the material that would have to be used would have to be light, have excellent conductivity and extreme tensile strength. Ice would be the worst element for a shield.

Final notes:
I don’t think "heatâ€

[dandandaman]

[quote="MKruer"]Final notes:
I don’t think "heatâ€

[DiGuru]

The best way to protect against lasers, is indeed to get rid of the energy by vaporizing something.

Using a very strong material (like titanium) as an armor would fail, it would melt and vaporize as well. Unless you embed superconductors within the hull. But, if you do that and you have no active way to get rid of heat, you would cook yourself.

That's why an ice armor works: by vaporizing it, you get rid of the energy.

For material impacts ice would be very bad indeed. But a massive titanium armor would be bad as well. You need to get rid of the kinetic energy. You need the armor to be able to deform and you need soft layers that project the energy sideways.

Layers of strong stuff, with layers of soft stuff in between. The strong layers deform, thereby compressing the soft layers. That way, the energy spreads out over a larger and larger area, untill it is dispersed.

So, any way you look at it, ALL armors are destoyed while they do their job. ALL of them have to be fixed/replaced quite regulary.

[DiGuru]

If you want the ice to last, you need to spray a plastic coating on top and attach that to the hull. Otherwise the ice would slowly sublimate.

Sublimating ice for forced cooling would work as well, so if you want to use it for that, just don't spray plastic on top of the ice.

Al in all, a thick layer of ice on top of the regular armor would be a good thing for a space ship that has to handle lots of energy.

[mkruer]

If you want the ice to last, you need to spray a plastic coating on top and attach that to the hull. Otherwise the ice would slowly sublimate.

Sublimating ice for forced cooling would work as well, so if you want to use it for that, just don't spray plastic on top of the ice.

Al in all, a thick layer of ice on top of the regular armor would be a good thing for a space ship that has to handle lots of energy.

This entire thread is being moved due to being of no relevance to Rylix.

[DiGuru]

Ok.

What do we do with ice armor? I think it would be great, and I do not think an armor that would shrug off 'small' hits (armor factor) but would have a percentage to allow damage would be very realistic.

An I think armor is destroyed while protecting you.

What do you think?

[FlyingAce]

I think a reflective metal would be best. you'ld have to hit it with a conventional weapon before lasers would affect it.

[DiGuru]

I think a reflective metal would be best. you'ld have to hit it with a conventional weapon before lasers would affect it.

Well. Yes. It might work, in the future. But mirrors are quite overrated as protection against lasers. For starters, they would only work against visible light lasers.

Pulse lasers would destroy them anyway, but they might offer a little bit of protection.

I think.

I don't know for sure.

[peteyg]

But mirrors are quite overrated as protection against lasers.

So is ice armor.

I would think water would be fairly valuable in space. Metallic armor of some kind seems like it would be a heck of a lot cheaper than ice armor, just because water probably isn't as readily available as metal up there.

[mkruer]

Steel 73.3 W/mK; 7.8 Density
Water 0.61 W/mK; 1.0 Density

What does this mean?

Simple in order for Ice i.e. Water to be as effective as Steel, you would have to have 120 times as think (73.3/0.61) consequently that also means that it would also end up weighing 15 times (120/7. as much. Ice armor sucks pound for pound (or for you non imperial system knowing people, kilo for kilo) but hey if you still want to use it go for it. I just hope you know you are a sitting duck for any other ship

[DiGuru]

Ok.

We have some armor. We shoot at it. What happens? It will be hit with a lot of energy. Kinetic, energy, whatever.

That energy will want to destroy anything it touches. That's the whole idea of it being used as a weapon in the first place.

So, we want an armor that can absorb all that energy without any other effects? It won't heat, it won't deform. Or whatever. But if you hit it with a weapon that is higher in the tech-tree than the armor, it will take damage.

Hum. A bomb-pumped laser is higher in the tech-tree than a nucleair bomb. But so is a rail gun. Or a laser pistol, for that matter.

Anyway, who cares? You just apply a certain amount of energy over a certain amount of surface. And that armor *HAS* to get rid of the energy.

Otherwise, you could have an armor that would not stand up against the simplest of laser pistols, but would not buckle if you detonated a nucleair bomb of several megatons right next to it.

So, YES, ice is a very bad conductor. And YES, it has little strength. And it would vaporize instantly when hit. And that is *EXACTLY* why it would be a great armor against lasers.

Duh.

[DiGuru]

But mirrors are quite overrated as protection against lasers.

So is ice armor.

I would think water would be fairly valuable in space. Metallic armor of some kind seems like it would be a heck of a lot cheaper than ice armor, just because water probably isn't as readily available as metal up there.

Yes, you could be right. But a thick, metal armor that would just shrug off everything beneath a certain threshold, and would be destroyed or give you a chance of a hit when above that threshold, would be really very unrealistic.

But a thick, compartimented armor of metal, that would vaporize in small sections, would be just as effective as ice. Just as long as it gets rid of the energy.

[DiGuru]

Ok, one last example. After this one, I quit this subject. I'm sorry if it is a bit harsh, but I do care.

If you wear a bullet-proof vest, made of kevlar, and you are hit by a small caliber bullet, what happens?

Well, the bullet won't penetrate. But it WILL transfer the kinetic energy. So you will feel like being hit with a sledgehammer.

That's why most bulletproof vests incorporate metal plates: to distribute the energy over a larger area.

Nothing much has changed from the middle ages, as far as personal armor is concerned. Only, they needed it to be solid and massive. So they had to pad the interior quite thoroughly. Just to break no bones when hit.

And the armor of a tank? Well, it protects against small arms. But it still deforms and needs to get rid of the energy. The whole outside of the tank is independendly suspended from the inside. Otherwise, the people on the inside would break bones when the outside is hit.

You kan kill a man by firing a bullet at him that is made of really soft stuff, like fat or water. The kinetic energy will make a large hole. If you throw a huge amount of energy against a spaceship, it WILL make an impact.

Unless you use magic armor. Like a force field. Whatever. Make it up to suit you. That way, it will behave just as you want it to.

[peteyg]

Energy beams don't have kinetic energy.

And shattering ice armor can't absorb that much energy relative to deforming metallic-type armor.

[dandandaman]

Energy beams don't have kinetic energy.

no, but they have momentum (well, I'm assuming your talking about lasers).....in which case momentum will be transferred in a localised area.....

of course, your going to have to have an awfully large powered laser.....so that effect is probebly ever going to happen...in fact, I probably shouldn't have bothered posting this at all

Dan.a

[mkruer]

Apparently you have never seen a laser cut though ice. One of two things happens. First is that if the laser is a low tempter laser the laser still goes through the ice like a hot knife through butter. If the laser is higher tempter laser, the ice tends to explode. This notion that you have that about using the particles that where blown off to protect you against a second attack is laughable at best, the physics just don’t add up for two reason. Lasers are stopped by either dense objects that can suck up the energy faster then the weapon/device can output or by reflecting the energy away. Ice does neither without great amounts. Second the particles that you would use to defended the ship would expand to far to great to be of any real use. Also if the ship was outside of a planets protective magnetic envelope, the solar wind would just blow the particles away leaving you exposed. For all intensive porpoises a mirror would be much better then ice shield would ever will, and unless you can prove otherwise I think most would agree that ice would be pointless. But to make you “feelâ€

[dandandaman]

[quote="MKruer"]Apparently you have never seen a laser cut though ice. One of two things happens. First is that if the laser is a low tempter laser the laser still goes through the ice like a hot knife through butter. If the laser is higher tempter laser, the ice tends to explode. This notion that you have that about using the particles that where blown off to protect you against a second attack is laughable at best, the physics just don’t add up for two reason. Lasers are stopped by either dense objects that can suck up the energy faster then the weapon/device can output or by reflecting the energy away. Ice does neither without great amounts. Second the particles that you would use to defended the ship would expand to far to great to be of any real use. Also if the ship was outside of a planets protective magnetic envelope, the solar wind would just blow the particles away leaving you exposed. For all intensive porpoises a mirror would be much better then ice shield would ever will, and unless you can prove otherwise I think most would agree that ice would be pointless. But to make you “feelâ€