Water flow in GPM and velocity question
Water flow in GPM and velocity question
(OP)
If I have a 35' diameter pipe at 326 PSI, how much water (seawater) would flow through this pipe in GPM? And at what velocity would this be flowing at? thanks for the help!





RE: Water flow in GPM and velocity question
1. What kind of pipe is this?
2. What is the slope of the pipe?
3. What is the static head?
4. What is the length of the pipe?
5. What is the tailwater elevation?
6. What are the head losses in the system?
It sounds to me like you are dealing with a penstock situation in a hydraulic power plant.
Mike McCann
MMC Engineering
RE: Water flow in GPM and velocity question
length?
elevation of inlet and outlet?
inlet pressure or head?
outet pressure or head?
pipe material?
http://virtualpipeline.spaces.msn.com
"What gets us into trouble is not what we don't know, its what we know for sure" - Mark Twain
RE: Water flow in GPM and velocity question
RE: Water flow in GPM and velocity question
The flow and velocity changes according to the conditions at the outlet of the stream. With the same inlet head as you have on the outlet, as shown in your diagram, you get zero flow, zero velocity.
http://virtualpipeline.spaces.msn.com
"What gets us into trouble is not what we don't know, its what we know for sure" - Mark Twain
RE: Water flow in GPM and velocity question
RE: Water flow in GPM and velocity question
RE: Water flow in GPM and velocity question
There are a lot of things going on here, and one is the limiting factor of the whole picture, which will determine the ultimate flow through the system and your penstock.
Mike McCann
MMC Engineering
RE: Water flow in GPM and velocity question
http://virtualpipeline.spaces.msn.com
"What gets us into trouble is not what we don't know, its what we know for sure" - Mark Twain
RE: Water flow in GPM and velocity question
RE: Water flow in GPM and velocity question
RE: Water flow in GPM and velocity question
RE: Water flow in GPM and velocity question
1. The maximum flow through the pipes are one thing, but as already explained by others, and common when all the factors you have mentioned are known, is the turbine manufacturor to give 'the maximum throughflow' of the turbine. This is just as usual as a pump manufactorer to give a pump capacity.
2. All turbine manufacturors will stall at your seawater question, although the material technology is well known in ship pump technology, offshore applications and seawater cooling. Also even worldwide for seawater turbine newer/existing or developing projects, although for lower pressures (Norway and other nations).
You could try to ask a turbine manufacturor for a budget approximation, unbinding price and ubinding performance (throughflow) based on freshwater to get an approximation. Try European or others than US if you haven't done that already. If positive answer try to get accuracy limits (plus minus xx%). You will even then have the question if this can be transferred to seawater without corrosion and cavitation problems. Exotic materials needed!
3. Based on the turbine designed maximum througlet you can check the velocity in the pipe and calculate the loss in pipe, an approximation based on pipelength, layout, restriction, component and roughness. However: the limitation is what the turbine can withstand and produce, not the maximum flow through the pipeline, which is high! As an example for freshwater turbine inlet ball valves can run as high as 17m/s, but more common are perhaps 6-8m/s?
See my point? You have to find that turbine/generator supplier to hold your hand!
RE: Water flow in GPM and velocity question
rmw