Anton Vs Dora

[grafspee]

1 hour ago, LeCuvier said:

Yes, a pressure change in liquid propagates at very high velocity, so a pressure drop will propagate through the liquid volume very quickly.
However, I'm not happy with the second statement. If the system went "all steam" very quickly you would see a brutal pressure increase (because the volume cannot increase by a factor of 5000 in the confined space of the cooling system) which in my layman's assessment might tear the cooling system apart.

I was talking about situation where vapor would generate only near hole in cooling system then venting out only steam would give a lot of time before coolant will vent out. But this is not a case, after cooling system is hit momentarily pressure drop will happen inducing vapor appearance at engine hot spots this would rise pressure again which would push out liquid coolant through hole in system. Instant whole coolant going off to steam would require immense amount of energy that won't happen ever.

If the hole would be big enough expansion of small amount of coolant boiling out in to vapor at engine's hot spots will easily blow remaining coolant out. 1 liter of water when goes in to steam has volume of 5000 liters. Even small amount of coolant boiling off is capable of pushing out everything out of the system.

[Bozon]

In a pressurized system if the hole is small enough, the pressure will drop to the point where the hottest water will start steaming. At that point the pressure will stabilize and the rate of steaming will equal the rate of volume vented out of the system - a quasi steady state. However, the temporary stabilization of pressure only keeps the venting rate high, so this is not a great blessing…

If the hole is big enough that the system will not reach a quasi steady state it means that the venting rate is so high that all the water boiling everywhere can’t even equalize it and you loose all the coolant in seconds.