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Turkish Directed Energy Weapons

You know there is different kinds of ceramics right, what you show is an average fire brick. Another point is distance between laser and missile will be not 1 meter thus greatly reducing lasers efficiency.

Focus is such that it cuts steel girders from a kilometer away. While your ceramic tile coating is sort of valid, there are a few drawbacks-namely it could never be as thick as on the space shuttle and it would need to absorb 100kW worth of energy in a space of a second and a half. And you could never coat all the stuff with it, like mortar , artillery shells and such.
I do not know the heat conversion formulas as i am no physicist, but from laser related forums people (that have lasers) say even a mW laser can give you burns. And we are talking about kW.

As of now, the doctrine would be to use lasers as a complementary method of defense, together with conventional systems.
 
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I was refering to the fact mirror reflects light of all frequencies on the basis of free electrons on it's surface that can absorb photons and then re-emits them. So, it stores energy, before it gives it away again, albeit for a very short time.

This is a complex arguments. There are mirrors available which would reflect terawatt beams, with intensities in terawatt per cm2. So reflecting a kW beam focused from a few km away should not be a big deal. A important factor would be heat conductivity, how fast it can dump excess heat.
A better example would be, the optics used for the laser consists of mirrors! Those mirrors do stand the heat of the laser, albeit unfocused. Even if it does deforms, you would expect avionics to correct flight path to an extent. A missile would not have to undergo multiple laser shots, as the next shot takes time. But none of the mirror available now would survive high speeds.

You know there is different kinds of ceramics right, what you show is an average fire brick. Another point is distance between laser and missile will be not 1 meter thus greatly reducing lasers efficiency.

Focus of the laser can be defined for a few km away. And ceramics have good insulation, but not necessarily a very high melting point compared to metal. And we are talking about few 10s of kW of laser. That is way to high! A few hundred watts CO2 laser is used for cutting metal.

I was refering to the fact mirror reflects light of all frequencies on the basis of free electrons on it's surface that can absorb photons and then re-emits them. So, it stores energy, before it gives it away again, albeit for a very short time.

This is a complex arguments. There are mirrors available which would reflect terawatt beams, with intensities in terawatt per cm2. So reflecting a kW beam focused from a few km away should not be a big deal. A important factor would be heat conductivity, how fast it can dump excess heat.
A better example would be, the optics used for the laser consists of mirrors! Those mirrors do stand the heat of the laser, albeit unfocused. Even if it does deforms, you would expect avionics to correct flight path to an extent. A missile would not have to undergo multiple laser shots, as the next shot takes time. But none of the mirror available now would survive high speeds.

You know there is different kinds of ceramics right, what you show is an average fire brick. Another point is distance between laser and missile will be not 1 meter thus greatly reducing lasers efficiency.

Focus of the laser can be defined for a few km away. And ceramics have good insulation, but not necessarily a very high melting point compared to metal. And we are talking about few 10s of kW of laser. That is way to high! A few hundred watts CO2 laser is used for cutting metal.
 
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This is a complex arguments. There are mirrors available which would reflect terawatt beams, with intensities in terawatt per cm2. So reflecting a kW beam focused from a few km away should not be a big deal. A important factor would be heat conductivity, how fast it can dump excess heat.

Can they be put on a missile? :)

A better example would be, the optics used for the laser consists of mirrors! Those mirrors do stand the heat of the laser, albeit unfocused. Even if it does deforms, you would expect avionics to correct flight path to an extent. A missile would not have to undergo multiple laser shots, as the next shot takes time. But none of the mirror available now would survive high speeds.

When i was talking about deforming i meant mission kill, parts flying off the missile, disrupting aerodynamics to such an extent the stabilization and guidance couldn't keep up.



Focus of the laser can be defined for a few km away. And ceramics have good insulation, but not necessarily a very high melting point compared to metal. And we are talking about few 10s of kW of laser. That is way to high! A few hundred watts CO2 laser is used for cutting metal.

Chemical lasers like the CO2 you mentioned are a dead end in military research. Solid state, 30kW+20kW:

was tested on numerous targets including a 15 mm thick steel girder that it was able to slice from a distance of 1 km.

DailyTech - Experimental German Lasers Destroy Drones, Simulated Mortars
 
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Can they be put on a missile? :)

They cant be, this is what I mentioned many times. That mirrors would not survive high speeds.

When i was talking about deforming i meant mission kill, parts flying off the missile, disrupting aerodynamics to such an extent the stabilization and guidance couldn't keep up.

Lasers can only kill a small part of the missile. Remember, it is focused, on a small area. The guidance/stabilizing system, etc determines how much damage it can take.
For example:
Kim_campbell_damage_a10.jpg

This plane flew for an hour in this condition.

I am no expert on this so I cant comment on how much damage is, well, too much.

Chemical lasers like the CO2 you mentioned are a dead end in military research. Solid state, 30kW+20kW:

Boeing used COIL. Chemical Oxygen Iodine Laser. Goes to 20 kW, can be increased. In fact, since it is direct conversion of chemical energy to laser, it is more compact, in the sense of power to weight ratio. Though I do like solid state lasers more than chemical.
BTW, CO2 isn't a chemical laser.
 
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Lasers can only kill a small part of the missile. Remember, it is focused, on a small area. The guidance/stabilizing system, etc determines how much damage it can take.

Well, you saw the video posted above. It punctured a hole and what was left lost direction sooner then a second after that.
 
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Well, you saw the video posted above. It punctured a hole and what was left lost direction sooner then a second after that.

We were discussing mirrors. Mirrors would reflect most of the energy, so the damage would not be that great. Laser would not be able to penetrate the hull. Mirrors should be able to reflect > 90% energy.

For example, 20 kW for 5 seconds = 100 kJ. Reflected 90 % = absorbed 10 kJ

10 kJ would be able to raise temperature of 100 gm of aluminum by about 110 degrees. If it is not already close to melting point, than this is certainly not enough.

Metals - Specific Heats
 
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We were discussing mirrors. Mirrors would reflect most of the energy, so the damage would not be that great. Laser would not be able to penetrate the hull. Mirrors should be able to reflect > 90% energy.

For example, 20 kW for 5 seconds = 100 kJ. Reflected 90 % = absorbed 10 kJ

10 kJ would be able to raise temperature of 100 gm of aluminum by about 110 degrees. If it is not already close to melting point, than this is certainly not enough.

Metals - Specific Heats

I see, nice explanation. :)

Though i personally think it would not be 20kW (even today's non-operational ones are 50kW+)and i have troubles with your temperature estimate. Namely you've taken 100gm unit which fills a surface bigger then what the laser hits, which would be a spot on which all the heat would come down.
 
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I see, nice explanation. :)

Though i personally think it would not be 20kW (even today's non-operational ones are 50kW+)and i have troubles with your temperature estimate. Namely you've taken 100gm unit which fills a surface bigger then what the laser hits, which would be a spot on which all the heat would come down.

I took 20 kW/5 sec from Boeing's RADIC laser (I would be happy if you can correct the figures!).

Initial beam diameter is 20in = 50 cm.
Lets suppose it is targeting a missile 20 km away.

Beam divergence - Wikipedia, the free encyclopedia
Dm = 50 cm
theta = Dm/f = 0.5 m / 20000 m = 1/40000
spot size = 2*lambda/pi*theta = (2*2*10^-6)/(pi*(1/40000))

Theoretical minimum spot size (radius) would be ~ 5 cm.
That means spot size area is ~ 75 cm2.

For a 5 mm thick sheet of aluminum, total volume is 37.5 cm3. For density 2.7 gm/cm3, weight is 101 gm.
 
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I took 20 kW/5 sec from Boeing's RADIC laser (I would be happy if you can correct the figures!).

Initial beam diameter is 20in = 50 cm.
Lets suppose it is targeting a missile 20 km away.

Beam divergence - Wikipedia, the free encyclopedia
Dm = 50 cm
theta = Dm/f = 0.5 m / 20000 m = 1/40000
spot size = 2*lambda/pi*theta = (2*2*10^-6)/(pi*(1/40000))

Theoretical minimum spot size (radius) would be ~ 5 cm.
That means spot size area is ~ 75 cm.

For a 5 mm thick sheet of aluminum, total volume is 37.5 cm3. For density 2.7 gm/cm3, weight is 101 gm.

Are you an Physicist?
 
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I took 20 kW/5 sec from Boeing's RADIC laser (I would be happy if you can correct the figures!).

Initial beam diameter is 20in = 50 cm.
Lets suppose it is targeting a missile 20 km away.

Beam divergence - Wikipedia, the free encyclopedia
Dm = 50 cm
theta = Dm/f = 0.5 m / 20000 m = 1/40000
spot size = 2*lambda/pi*theta = (2*2*10^-6)/(pi*(1/40000))

Theoretical minimum spot size (radius) would be ~ 5 cm.
That means spot size area is ~ 75 cm2.

For a 5 mm thick sheet of aluminum, total volume is 37.5 cm3. For density 2.7 gm/cm3, weight is 101 gm.

Well, you should have continued with heat absorption calculations if you already went this far, because this calculation doesn't really disprove anything, you only enumerated my assertion of a small ***. :P

Try taking 25kJ (50kW laser and 90% reflectivity) spread over 75 cm2 aluminium sheet. How much heat does that produce?

I'd try myself, but i'll get hopelessly lost in the formula's, it's early morning and my physics classes are a good decade and lots of parties away. :cry:

btw, Google search on "Boeing's RADIC laser" gives nothing.
 
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Well, you should have continued with heat absorption calculations if you already went this far, because this calculation doesn't really disprove anything, you only enumerated my assertion of a small ***. :P

Try taking 25kJ (50kW laser and 90% reflectivity) spread over 75 cm2 aluminium sheet. How much heat does that produce?

I'd try myself, but i'll get hopelessly lost in the formula's, it's early morning and my physics classes are a good decade and lots of parties away. :cry:

btw, Google search on "Boeing's RADIC laser" gives nothing.

There is not much to calculate. Increase the energy 2 and half times, the temperature would increase by the same ratio - 275 kelvins. Unless you have hit the melting point, where most of the energy would go into melting the metal and not increasing the temperature.

Latent heat of melting for Al is 350 times higher than specific - 321 kJ/kg.
Latent Heat of Melting of some common Materials

So to melt 100 gm of Al, 32kJ would be required, more than 50kW/25kJ. So depending on conductivity and initial temp, lot less than 100 gm would be melted.

But all this assertions based on reflectivity of 90%, which I doubt can be achieved for now.

RADICL, Research Assessment, Device Improvement Chemical Laser, is a 20 kW COIL laser tested by the United States Air Force in around 1998.[2]

COIL is the main weapon laser for the military airborne laser and advanced tactical laser programs. On February 11, 2010, this weapon was successfully deployed to shoot down a missile off the central California coast in a test conducted with a laser aboard a Boeing jumbo jet that took off from the Point Mugu Naval Air Warfare Center (for more details, see Boeing YAL-1.) [3]

Chemical oxygen iodine laser - Wikipedia, the free encyclopedia
Boeing YAL-1 - Wikipedia, the free encyclopedia

WOW! I'm so jealous of you in-depth knowledge of these things. Do you do particle physics? Or quantum Mechanics? What's your main research area?

In-depth knowledge!!
No way. In fact even my field is a potpourri. Many fields, material, optics, plasma, electro magnetism, high energy physics and more. But lets not talk about my research, I am running away from it here! :P
 
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Well, you should have continued with heat absorption calculations if you already went this far, because this calculation doesn't really disprove anything, you only enumerated my assertion of a small ***. :P

Try taking 25kJ (50kW laser and 90% reflectivity) spread over 75 cm2 aluminium sheet. How much heat does that produce?

I'd try myself, but i'll get hopelessly lost in the formula's, it's early morning and my physics classes are a good decade and lots of parties away. :cry:

btw, Google search on "Boeing's RADIC laser" gives nothing.

Oops, I guess I messed up. I mixed two lasers, the RADICL used by USAF in 1998 and the one used by Boeing. Both being COIL. The RADICL being the 20kW one.

Boeing YAL-1 - Wikipedia, the free encyclopedia

When fired, the laser produces enough energy in a five-second burst to power a typical American household for more than an hour.
Which, assuming a modest 1 kwH is 3.6 MJ or 720 kw ! Whose 10 % would be 360 kJ, which is quite high.
 
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