Back driving a rotary pump

[DrexelME]

Hello,

I'm not sure if its the right term for this but can a rotary or centrifugal pump be driven by a pressure differential across the pump gears? I'm looking to create rotary shaft motion with fluid flow through a cavity.

My first thoughts on this were to force flow through a solid piston with helical ports through it which only spun the fluid and didn't rotate the piston so I assume there is a force balance I'm not aware of in that scenario. I was thinking along the lines of a helical flow meter.

Regards,
Ryan M.

 

[bimr]

It is possible with a rotary pump, not a centrifugal. The pump efficiency will be low.

 

[Artisi]

bimr: a centrifugal can indeed be driven by using reverse flow. A good example is --

https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[LittleInch]

DrexelME,

You'll find more information if you look for water turbines.

They are designed and built differently and with wildly different efficiencies.

These guys make specific machines to capture power from pipelines and other process plants.

http://www.energyrecovery.com/oil-gas/transmission-pipelines/

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[DrexelME]

There is one part to this I guess I left out that is quite important. Flow reverses often and suddenly so a turbine and many pump designs wouldn't work which is why I was looking at a helix. Perhaps some form of a gear pump or rotary pump is the only way this will work in both directions.

 

[LittleInch]

Perhaps have two and just add non return valves on the inlet to the turbine and the outlet of the pump?

try googling "using pumps as turbines" - lots of data

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[DrexelME]

Two with check valves may be possible but trying to avoid due to doubling cost, weight, and space.

 

[LittleInch]

That's up to you, but depends on what needs to be the most efficient, the pump or the turbine. Most are optimised to one or the other.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Artisi]

Why is flow reversing, I was to understand you wanted to use the "pump" as a driving unit - not a pumping unit.
Think you should expand your thinking a little so we all understand.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[DrexelME]

It is in oil
Flow reverses often and suddenly
1-2" bore tubing so pretty small, low flow velocities. Completely custom design is expected.
I need the oil to force the pump/turbine shaft to rotate CW/CCW as flow moves forward/reverse through it with good response on changes in direction.

I 3D printed the helical "piston" which didn't work. Just trying to figure out which style pump would be best without physically testing them all. I'm pretty sure a gear pump would work so I guess a rotary positive displacement pump would work for the same reasons.

 

[LittleInch]

You need to look at hydraulic motors.

Try the fluid power forum and add details such as size of pipe, flow, fluid, pressure, power etc and you should get some help there or look at the posts in that forum for the same question

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[DrexelME]

Thanks.

 

[hydtools]

Look at bi-directional hydraulic gear motors. e.g. Oildyne.

Ted