Quote:
Originally Posted by some_other_dave
For sprint races, individuals have done lots of different things for cooling over the years.
I think it was in the 60s that Porsche experimented with "Jet Cooling" or something like that. No fan; it used some odd effect of the exhaust or something. They dropped it because it was VERY VERY LOUD.
-soD
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Any 'jet' of high-velocity will have low static pressure.
A stationary fluid exposed to the jet will be induced to flow towards it in an effort to achieve pressure equilibrium.
This goes back to Daniel Bernoulli and his venturi which the French perfume industry latched onto,which was also the premise for the carburetor and syphon-feed spray gun.
In HVAC work,some hydronic systems will use a forced-air venturi to induce airflow mixing across the heat-exchanger before discharge into the conditioned space.
Also,venturis can be used for refrigeration.A compressed air source is all that is needed.With no moving parts,a venturi can provide reliable cooling.One of my brothers did a stint in a steel mill,cutting yellow-hot steel as is moved from an extruder.He wore an aluminized 'spacesuit' which incorporated a venturi cooling system to keep his bacon from frying.
It is this venturi effect which causes the wingtip contrails on jets.As the wingtip pressure differentials spin up into the vortex,the core pressure falls to a vacuum.Upon passage,heat of compression is released as in an expansion valve in an air conditioner,moving the air below dewpoint,causing the water vapor to condense into visible droplets.