h a l f b a k e r yI CAN HAZ CROISSANTZ?
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Wonder of that would work. Seems like you might be able to significantly extend the reach of the water hose.
Don't know if you'd be able to focus that interior stream enough to make it help or if it would just make the stream disburse earlier.
Wonder if doing something like putting some solid
mass into the stream like ice crystals, or beads of some gel flame retardant semi solid could give it some oomph.
Dunno, be interesting to look into.
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How about a repurposing of the good old flamethrower tank? Tanks are pretty fire resistant, they squirt fuel + a gelling agent a good distance. Water plus a gelling agent and a towed extra supply would work, could move deep into a fire. |
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Yea, I do think the idea of adding some mass then using another mechanism might be at least worth looking into eh? Correct me if I'm wrong, but in terms of aerodynamics alone you're get more distance out of your velocity with gell that's not going to be broken up by that airflow no? |
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As far as more-fireproofer tanks, just remote those bad boys, roll 'em right into the fire. From flamethrower to flameslower. |
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"Tanks For Peace". (c) (tm) all rights reserved. |
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I think the problem with using steam is that the pressure you get from it comes due to it being above the boiling point. If you are mixing it with liquid water, it'll heat that up (which isn't a benefit) and cool itself down, returning to liquid form and dropping the pressure. |
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Compressed gas, on the other hand, might give you more of a 'throw' with a limited amount of liquid. Not sure how much help it would actually be, though. |
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A slurry of cold water with frozen ice beads seems interesting - you'd have the latent heat of fusion contributing to the cooling effect. It might work - if the pumps can handle it. You'd need to prepare it ahead of time, of course, and it would be relatively expensive.
Maybe a good fit for first responder truck units which have to carry their own water supply.
The other advantage is of course that at outreach events you could add flavouring and turn the firetruck into an enormous Slush Puppie machine. |
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Mmm, like the Slush Puppies benefit. We called them "Slurpies" which in restrspect is kind of gross compared to Sluch Puppies. |
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In honour of the memory of 8th of 7, I should mention that I was reminded of the only development in rocket propulsion which seemed to impress John D. Clark, author of "Ignition!", was the use of slush hydrogen.
They were doing that to increase density, of course (hydrogen being the best propellant with the worst density) - and water ice is less dense than liquid. So how much benefit (or deficit) would we get per unit of ice? |
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Well, the density of ice is 0.9 g/cm^3, rather than 1.0 for water. Give or take. |
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The specific latent heat of fusion for water is 334 kJ per kg.
The specific heat capacity of water is 4.2 kJ per kg per degree Celsius, or 420 kJ per kg over the full liquid range
The specific heat of vaporisation for water 2260 kJ/kg |
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So for 1 litre of water at, say, 4 degrees C, we'd extract about 2663 kJ of energy from the fire through its evaporation. |
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And for 1 decimetre of ice at 0 degrees C, we'd extract about 2713 kJ. |
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Okay, so slightly more, but not enormously more. Maybe 2%. And that's only for the actual ice component, unfortunately - the slush wouldn't be 100% ice. If you could have (optimistically) half and half, it would be a 1% benefit in overall cooling capacity for the volume (using about 5% less water). |
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I guess that explains why it's not routinely done - it's not really worth building up the massive infrastructure involved for this very small benefit. |
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//water ice is less dense than liquid// |
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That's a trip, I was just watching a documentary on water yesterday talking about how that odd characteristic of water it a big deal to life itself. If frozen water sank like other liquids life has a real hard time in water, at least fresh water. Winter would kill everything. |
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So I'm not thinking about fire putting out ability so much as the stream being less susceptible to aerodynamic drag and maybe going further as a result. Dunno, can you throw Slushies further than water? Seems like you'd be able to. Like the difference between throwing a handful of plastic beads vs those beads if they were crushed into a powder. Is that an applicable analogy? Dunno. |
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Interesting question - I have no real idea either. |
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But as you said in a comment above, the optimal projection happens with a laminar flow which doesn't break up into droplets for as long as possible. I suspect (but don't know) that adding lumps of ice would interfere with that - and likely it would also be harder to pump. |
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Yea, to be honest this is one of those thinly veiled questions packaged as an idea. I do that sometimes. |
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//Seems like you might be able to significantly extend the reach of the water hose.// |
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I was tinkering with the best application for this but I think you might have nailed it.
I can't remember which culture but in ancient times water would be made to passively vortex down a drain and the trapped air allowed it to be lifted to far greater heights than non swirling non<later edits> vortexing water. |
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Nowadays you'd just use an impeller at the bottom of a circular tank and if the gas introduced into the stream of water was CO2 instead of air it should put out fires far better than water alone and shoot for a greater distance as well. |
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