Water pump question

sean9461

I am trying to buy a water pump for a pond fountain however when looking for the right powered pump I come up with a problem I'm not sure how the water pressure spreads through a system

Basically the pond needs to have 5 or so jets of water shooting up. I plan on doing it with one pump due to budget saving.

Now if the pump is attached to a pipe of say pvc then has a T junction every 50cm for example what happens to the pressure

Would the furthest away T have a much smaller and less powerful jet of water?

Would the water pressure half at every T? So 100% pressure to begin with, when it gets to first T 50% pressure gets out then 50% passes to next T then 25% gets out of that T and rest continues then 12.5% and so on?

Or does it simply automatically push out equal pressure through all Ts?

Sorry if this is a confusing post as it's baffling me too so it's hard to explain!

If somebody can explain this too me it would be great thanks

keith969

It depends on the size of the pipe, the distance to each junction and the size of the jet nozzles.

To keep the pressure drop between the first and last t junction small, the pipe needs to be much wider than the nozzles. The analogy is an electrical circuit where you have lights at regular intervals along a cable - if you want them of equal brightness the cable thickness (resistance) has to be small compared to the resistance of the bulbs.

sean9461

The pipe would be the size of the hole in the pump to connect to it. So I just have two have the connecting t's 1/5 the size of the main pipe to equally distrobute 1 5ths of the water between each T?

If that's the only way to do it then it could be difficult depending on the size of the hole in the pump

keith969

So you just have T junctions with no further restriction of pipe width to where the water comes out? In which case you will lose significant pressure for each junction.

sean9461

So if I have a 5cm pipe coming out of a 5cm hole in a pump I would need each T to have a 1cm pipe attached two have even distribution of pressure?

SplanK

You would probably be better introducing some sort of inline valve to adjust the flow to each jet. The closet exit to the pump outlet will be the least resistant this most of the water will exit via that jet and will reduce as each exit is passed.


The valve prevents you from having to try and size each pipe and allows you to fine tune your 5x outlets precisely and more accurately, resulting in a balanced display.