4 ms·
Or just something that gets smoky when it burns, then the energy is deposited entirely into the smoke boundary layer (and might even make a nice reflective plas
by chris_va 2y ago
Or just something that gets smoky when it burns, then the energy is deposited entirely into the smoke boundary layer (and might even make a nice reflective plasma).
- ssl-3 2y agoIt would need to be a neutral-density-ish smoke, wouldn't it? If my dealings with (much, much) smaller lasers are an indication, "regular" smoke from laser-heated things is generally buoyant in air, and would tend to just float up and away from a presumably-horizontal beam. It seems like this would limit the smoke's abilities to diffuse and absorb the energy.
- chris_va 2y agoYes it would ablate at some rate, based on the drag, convective buoyancy, etc. If the smoke is optically thick at all, even if it pushed away almost immediately, the wall ablation rate would probably be a couple orders of magnitude lower than if the laser hit the wall directly... If you want a fun read, the Galileo probe wall ablation paper is fun, the re-entry power density (at the wall!) was ~10kW/cm^2.
- gpm 2y agoI'd be sort of surprised if the buoyancy mattered much in the face of the amount of air something needs to move to fly. On the time frames that buoyancy acts in I imagine (without data) it's no longer around the drone anyways.
- Retric 2y agoAs I understand it defenses depend greatly on pulse duration. Rotation dramatically increases effective armor thickness if energy is delivered over a long time frame etc. But drop to the nanosecond range and a cloud of plasma which used to be the armor is going to between the laser and what’s left of the armor. That said, you don’t need to drill through a target, a jet of ablated material means an equal and opposite force is going in the other direction. Really though the biggest limitation of a laser defense system is pure kinetic kill weapons. Big thing moving Mach 2+ is deadly even without pinpoint accuracy or being filled with high explosives.
- ortusdux 2y agoIntumescent paint would do the trick. Intumescent paints are considered the lightest form of passive fire protection. An intumescent is a coating that, when exposed to heat, is rapidly transformed through sublimation, and expands many times its original thickness (up to 100 times), to form a stable, carbonaceous char. The resultant char reduces the conduction of heat from the fire to the substrate, delaying the time it takes to reach structural failure. I'm considering getting some for my kitchen remodel. https://www.nullifire.com/en-gb/expert-insights/expert-advice/the-different-types-of-intumescent-coatings-their-benefits/ https://www.nullifire.com/en-gb/expert-insights/expert-advic...