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Old 03-20-2011, 04:57 PM   #11
vex
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Quote:
Originally Posted by NoDOHC View Post
I know that you know this, but to clarify the terms for those that may be confused, cavitation occurs in a liquid pump when either a dissolved gas is brought out of solution or the liquid evaporates. Both conditions occur under high vacuum on the impeller inlet. Liquid droplets in a normally gaseous fluid can't really be called cavitation.

I was more speaking of mechanical damage by fatigue loading.

I was thinking that the sudden pressure drop across the surface of the impeller would cause the droplets to become gaseous and then collapse once exposed to additional pressure--but then again, does an impeller actually impart a pressure differential across the blades? The more I think about it the less likely it seems that they would. The only way I can think of this occurring is if it were deposited in a vacuum, induced into a gaseous state while maintaining surface integrity/tension of the droplet, only to collapse when exposed to the positive pressure in the housing of the turbo.

As for the fatigue loading I don't see that causing much of an issue either unless the injection point is unbalanced causing additional mass to only enter one specific location on the impeller.
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