Post by Anon1 on Aug 31, 2018 19:39:18 GMT
Aug 23, 2018 18:29:28 GMT Anon1 said:
What is stopping the stronger laser from drilling through the shutters of the weaker lasers before the weaker lasers get into range? What's to stop it from drilling through the engines so that the weaker lasers not only never get into range but don't have a power supply?
Increasing the power by a factor of 100 increases the effective range from the same size aperture by a factor of 10. Increasing the aperture size by a factor of 10 increases the range by a factor of 10 if frequency and power are kept constant. Increasing the frequency (aka decreasing the wavelength) by a factor of 4, increasing the range by a factor of 4. So a 1 GW laser firing from an aperture 10 times wider at a frequency 4 times higher, will have 400 times the effective range of a 10 MW laser firing from the smaller aperture and lower frequency. And the ship carrying those smaller, weaker lasers will take a long time to cross that range. Time during which the big bad laser will get to drill through said ship.
A 1 GW, 200 nm, continuous wave laser firing through a 20 meter diameter aperture has a 1 meter diameter spot size at 81,967 km. It will drill a 1 meter wide hole through steel armor at a rate of 2.08 cm/s at that distance. If closing velocity is 100 km/s and your weaker lasers aren't effective until 1967 km, then your ship will have to get hit for 800 seconds before you get to fire back. During that time, said laser can drill through at least 16 meters of steel by adjusting its focus to maintain a 1 meter wide spot size. However if the spot size drops to .5 meters then the drill rate increases to 8.1 cm/s. At 0.2 meters the drill rate increases to 47.1 cm/s.
If the laser power goes up to 10 GW, then at 327,868.852459 km, the beam is 4 meters in diameter. It will drill a 4 meter diameter hole through steel at a rate of 1.3 cm/s. Change it to a 1kilohertz pulse laser firing 10 MJ, 10 nanosecond pulses and the laser will drill a 4 meter wide hole through steel at a rate of 9.74 cm/s. Now pump the power up to 100 GW by running the same pulse laser at 10 kilohertz and the drill up goes up to 97.4 cm/s with a 4 meter wide spot size. Or at 2.5 times the range, the spot size of the 100 GW version goes to 10 meters wide and the drill rate goes to 18.3 cm/s.
Welcome to the laser problem of space combat.
note: I used this site for laser damage calculations: panoptesv.com/SciFi/LaserDeathRay/DamageFromLaser.php
But tbh, the range disparity between the enemy laser and my counterlasers might not be as big as you suggest. I wouldnt use a 10MW agianst a GW. id prob use something 3-5 times smaller (like a 1GW against a 5GW). One more thing to consider, steel is a pretty shit antilaser armor. Have you tried this agains PE or Graphogel, or Silagel ?
Silica gel is mostly transparent to visible laser light. In reality, the laser will mostly go straight through it and hit whatever is behind it. The game messes up laser damage something terrible.
Remember, an aerogel is overwhelmingly empty space. It is so light because most of the space is empty.
As for polyethylene, A 10 GW laser with a 4 meter spot size would drill through it at a rate of 18.1 cm/s.
Carbon substances (graphene and carbon nanotubes) hold up better at only 7 mm/s of a continuous beam 10 GW laser with a 4 meter spot size, 2.83 cm/s with a 2 meter spot size, and 11.4 cm/s with a 1 meter spot size. However, if that 10 GW laser is a q-switched 10 nanosecond pulse laser, then you can get 2.24 cm/s drill rate with a 4 meter spot size.
Aerogel graphene is just $300 a gram, ultra-low density carbon. That means that it doesn't take as much energy to vaporize a cubic meter of aerogel graphene as it does to vaporize a cubic meter of regular graphene. At a density of 66 kg per cubic meter and a thermal conductivity of 0.0263 W/(m K), with all of graphene's other properties plugged in, I got a drill rate of 4 km/s using Luke Campbell's calculator.
A laser drilling through an aerogel is like a laser drilling through dirty air.