If you reach the "choked" condition at the exit of a pipe with a liquid/vapor two phase flow, does this mean that the velocity has reached Mach 1? Is there a shock wave that occurs at the exit? I have very limited knowledge of compressible flows so good references would be helpful.
2006-12-13 09:42:39 · 4 answers · asked by RyVu 2 in Science & Mathematics ➔ Engineering
I gotta go with "yes" on this one. Choked condition occurs because the flow has reached the speed of sound given the conditions of the flow in the pipe (temperature, pressure and density).
As far as "shock wave" - yes, there is a pressure gradient at the exit for choked flow.
2006-12-13 10:03:26 · answer #1 · answered by www.HaysEngineering.com 4 · 1⤊ 0⤋
Mach speed is the speed of sound in the air, and it's really variable depending to the atmospheric pressure, humidity (partial pressure of water vapour) and temperature.
When an object reach this critical speed the sound waves that it will produce will compress and act like a force against you, and you need much more energy to brake the wall and accelerate further.
choked condition into a pipe, you mean maybe the cavitation bubbles ? when you reach a critical speed inside a pipe the flow of the liquid will change from "laminar flow" to "turbolence flow", this can cause cavitation bubbles because the flow will have different pressures in different zones of the pipe. These are dangerous because they can really erode the pipe.
2006-12-13 09:55:47 · answer #2 · answered by scientific_boy3434 5 · 0⤊ 1⤋
Choked conditions are explained very concisely in this Wikipedia article.
m
2006-12-13 10:12:02 · answer #3 · answered by Mukluk 2 · 1⤊ 0⤋
No
2006-12-13 09:58:06 · answer #4 · answered by Anonymous · 0⤊ 1⤋