How long it will take flood a vertical pipe if the bottom of pipe cut
How long it will take flood a vertical pipe if the bottom of pipe cut
(OP)
HI! Could anyone help me? Water Depth is about 1km. the vertical pipe is also 1km length vertically and empty but we try to cut the bottom of pipe by blade so the water will flow inside the pipe from bottom. Do you know how to calculate the time to flood fully up to a sea level? Pipe size is ID is 25in. Cutting will take 2 hours and during the cutting, the cutting pipe gap(assumed 1in.)is very small. Objective is to see how much of pipe would flood during the cutting process before tool makes the complete cut. Thanks





RE: How long it will take flood a vertical pipe if the bottom of pipe cut
Water flow through pipes typically reaches a maximum velocity of 9-12 m/s. If the pipe was open on the bottom, a rough estimate is that it may take 1 1/2 minutes to fill the pipe.
RE: How long it will take flood a vertical pipe if the bottom of pipe cut
RE: How long it will take flood a vertical pipe if the bottom of pipe cut
RE: How long it will take flood a vertical pipe if the bottom of pipe cut
In water the volume of air halves for every 10m of depth. Additionally, a bubble rising through water experiences forces of fluid friction and turbulence. These create an opposing force proportional to velocity, so just as a body falling in the air reaches a terminal (maximum) velocity, so it is for a bubble when the frictional forces due to its upward velocity match the upthrust.
A rising air bubble in water reaches a velocity of approximately 2/3 * (square root(gR)) for a bubble of radius R. What this means to the sound is that whatever the bubble size it quickly reaches its final velocity. Now suppose a bunch of bubbles, some big, some small, were created deep in the water. The bigger ones will arrive at the surface first, followed by the smaller ones.
From the sea floor 800 meters down, it has been observed that it takes 20 minutes for methane bubbles to rise 300 meters. Based on that empirical data, one can guess approximately 60 minutes.
You might get a better answer in the diving forum.
RE: How long it will take flood a vertical pipe if the bottom of pipe cut
RE: How long it will take flood a vertical pipe if the bottom of pipe cut
Why wouldn't you flood the pipe before making the cut?
As a chem eng/metallurgist the first part of any answer I give starts with "It Depends"