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what is the relationship between cavitation of pumps and pressure of liquid and temperature of liquid?
I want to know the relation of cavitation and liquid pressure and temperature?
I want to know the relation of cavitation and liquid pressure and temperature?
Comments
3 years ago
"vapor pressure" is a good search term to help understand cavitation.
3 years ago
You guys really like answering homework questions it seems ;)
Answer 3 years ago
Fun to respond with each other when the OP is hopelessly under-educated about a subject.. Throwing high enough detail facts makes the the student either give up or learn something new.. Both are reasonable results in my way of thinking..
BTW I did learn cavitation is reduced as pressure increases..
And it does feel good to take a jab at stupid US politicians and Jap spies..
3 years ago
Intuitively, I would expect cavitation, like near a propeller blade in water, to become more active, as the temperature of the water is increased, or as the pressure of the water is decreased.
I mean, if I look at the phase diagram for water,
https://en.wikipedia.org/wiki/File:Phase_diagram_o...
and assuming I start in a point, in P-T space, somewhere the area that represents liquid water, from there a increase in temperature or a decrease in pressure will move the point closer to the line that separates liquid from vapor.
I guess what I am saying is, the distance from that line is sort of like a measure of how much energy is needed to go from liquid to vapor.
Based on that logic, I would guess that in water at 0 C, and 1000 atm, cold and at really high pressure, it would be difficult to make cavitation happen. In contrast, for water at 90 C and 1 atm, water that is almost boiling anyway, I would expect it would be easy to make cavitation happen.
Also I asked Google(r) to search for, "cavitation submarine screws temperature pressure", and one of the links I found, a Google Books look into a book titled, Military Technologies of the World [2 volumes], by T.W. Lee, has some words that seem to confirm this guess. Here's the quote, from the bottom of page 343:
3 years ago
Cavitation is lost mechanical energy in impeller style pumps...
Tell your teacher that pressurizing a liquid will raise the liquid temperature and the lost cavitation energy does also heat the liquid..
Answer 3 years ago
BTW cavitation is a very extensive https://en.wikipedia.org/wiki/Cavitation Science especially in Military submarines called the Silent Service. Propeller cavitation makes an underwater noise that enemy subs can detect and send a torpedo after you.
I have unpublished knowledge, about long ago the USA developing a very special propeller shape that did not cavitate.. But more then that, American engineers developed a one-of-a-kind of lathe that could machine the very special non-cavitating propellers.
Now, for some bizarre political reason, they the US turned this one-of-a-kind lathe over to a Japanese unamed company to manufacture the propellers for the US military submarines.
This unamed company reverse engineered the lathe and sold it to the Russians during the cold war times !
And that's a cavitation story about fleeting military secrets..