Science Question
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No worries young man . If you value your opinion over science and applied practical experience then by all means carry on but I fear you may learn some lessons the hard way.
Grouper is right. The pressure remains constant with depth not volume. His examples of the diver pretty much proves the fact. Notice when you stick a maxijet in a bucket and point it to the surface the turbulence/boil is only in the area the maxijet is pointing and it doesn't push the whole bucket of water up. The water in the bucket actually moves out of the way of the water being pushed up by the pump so the volume is not effecting the pump just the height. If you were to stick the pump in a bathtub that is the same depth it would not effect the height of the boil caused by the pump even though its probably 40 more gallons of water.
It is not the same,
A pump inside a container has virtually zero head as the pressure is equally the same on both inlet and outlet.
Once a pump has to pump water between to separate vessels the differential in pressure (if any) comes into play.
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Well guys I hooked a maxijet 1200 to a 3/4" pipe and a 12" pipe at the same height (50") above the supply container and the maxijet filled the same capture container(bowl not sure of its capacity) 5 seconds faster with the 12" than the 3/4" pipe did!
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My apologies. I was not trying to make a point.I was stating a fact that you were wrong. I seen no need to elaborate as your statement had no substance.
Edit:
I really truly did not know how to respond to this! It makes no sense. It was obvious to me that you had not researched this and simply stated your opinion not facts. If you want respect then present your ideas and opinions as such and not as an ignorant dogmatic statement! This why I really appeciate the ignore feature.
Last question, I promise:
Let's imagine an oil platform.
A pump pumping upward (bottom of the ocean to the rig) produces the same flow as the same pump (same pipe) pumping down (rig to bottom of the ocean)?!
In both scenarios the pump is always located at the origin of the pump chain.
Let's imagine an oil platform.
A pump pumping upward (bottom of the ocean to the rig) produces the same flow as the same pump (same pipe) pumping down (rig to bottom of the ocean)?!
In both scenarios the pump is always located at the origin of the pump chain.
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Not sure I understand the question maybe tomorrow pm when I bring the stand
Bernoulli's Equation people! Sufficient for a first approximation. P + 1/2MV^2 + (rho)gH = constant along a streamline. This is for an inviscid fluid however. If you want to add in friction, it's just a head loss term. Pipe friction (head loss) is proportional to flow velocity and surface roughness. So considering the same material, the larger diameter results in less friction. Proven by Grouper's experiment. Larger diameter = lower velocity when volumetric flow is held the same.
For the oil platform question, theoretically yes. Pumping from the bottom of the ocean, to just even with the surface, or the other way around, is only overcoming the frictional losses from the pipe. This is regardless of the pumps position (beginning, middle, or end) or flow direction (pushing or pulling). In practice, these situations would all vary however (pulling could cause cavitation in the pump, etc.)
For the oil platform question, theoretically yes. Pumping from the bottom of the ocean, to just even with the surface, or the other way around, is only overcoming the frictional losses from the pipe. This is regardless of the pumps position (beginning, middle, or end) or flow direction (pushing or pulling). In practice, these situations would all vary however (pulling could cause cavitation in the pump, etc.)
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I'd like to sincerely apologize to Sharkbait and blixem. While I stand by my statement that your opinion presented as a fact was wrong(incorrect) based on the laws of hydro dynamics, I do feel that that my singular word response was rude and should have been stated in a more polite manner.
how did this thread get so long?
the answer is no it makes no difference, if its a 1/4" pipe or a swimming pool, the height of the water will always be equal to the head pressure of the pump.
that is why units of pressure such as inches of water, feet of water, inches of mercury only have a length to them. The overall volume makes no difference. You are dealing with pressure which is force over area, change the area and the force changes along with it.
the answer is no it makes no difference, if its a 1/4" pipe or a swimming pool, the height of the water will always be equal to the head pressure of the pump.
that is why units of pressure such as inches of water, feet of water, inches of mercury only have a length to them. The overall volume makes no difference. You are dealing with pressure which is force over area, change the area and the force changes along with it.
