It all comes down to flow rate and initial temperature.
It’s impractical, but even a typical garden hose at satp puts out enough mass to consume 16MJ/m of heat assuming it all vaporizes.
For perspective, that’s like getting hit by a Toyota Camry at highway speed every 7.5 seconds.
Massive practicality issues but from a thermodynamics perspective it passes an initial check at least
We’re in a bushfire zone, even had one get close, late last year. We looked into suppression systems, and there’s two types - one has a series of garden sprinklers positioned on your roof gutters or overhangs. They get turned on to create a large, extended fan-type spray of water. The idea is not to extinguish a fire, but to absorb the heat so it doesn’t get hot enough locally to ignite your house.
The other type - which we chose - puts agricultural sprinkler heads on your roof peaks. Fed by a substantial pump from storage tanks ( 2 x 22,500 litre/5000 gallons), they throw in intersecting circles out to a distance of about 15 metres/50 feet. The idea is to saturate your roof and walls, and surrounding foliage sufficiently that it won’t ignite.
The real/fake answer is engineering school the real/real answer is playing “Oxygen Not Included” aka “Thermodynamics Simulator”.
