Abrupt direction changes

[Heinz]

Having a think about using multiple nozzles on my turbine and how to plumb them. I could make a multi pipe adapter for the end of the 100mm bore penstock and connect one feed pipe to each nozzle with just a gentle curve in each or I could use one larger bore pipe with a T piece on it for each nozzle. Obviously one pipe with T's is less work, but how much loss do you get with an abrupt change in direction like a T ?? 

H

[regen]

Hi Heinz,

I think any abrubt turn should be avoided. It may also be important to get equal flows at each nozzle or as equal as possible.  If i ever get to your stage (Currently still assessing viability) then i think i would look at bringing the manifold off the 4 inch rather like an old distributor cap and allow room to have a swept bend to each nozzle.Assuming 4 nozzles. having said that it would be reletive easy and quick to try the t piece method first to see if multi nozzle does give an improvement.

good luck
Regen

[knighty]

could you not use flexible hose from the end of your 100mm pipe to the nozzles ?


do you know the pressure at your nozzle ?


if you do, you could work out the maximum flow rate for your pipe at that pressure... and compare that to the water you have avalible...

if they're pretty close then you'll be better with swept bends...

but if the max flow for that pipe/pressure is a lot more than your water source can provide... then you have a bit of overhead and you can just go with the 90* bends :-)

[acresswell]

Could you find a Y-piece rather than a T-piece?

More time spent searching but less time spent bodging engineering...

[camillitech]

Morning Heinz,

smooth curves are always better than corners right enough but much depends on the diameter and the flow.



This set up that i was instructed to make by an expert some years ago struck me as being a bit on the 'sharp' side but it's performed really well with 32mm hose coming off each Tee to four nozzles of different sizes.



For the life in me I can't remember the exact flow rate but I think it was designed to operate between 1 and 10??lts/sec with anywhere between 1 and three nozzles open.

Mine on the Powerspout is just a 2" Tee on the end of the penstock with two 38mm flexible pipes coming off the end. I did try to find a 'Y' but couldn't.

Good luck, Paul

[Heinz]

Regen -
I was thinking along the distributor cap design but had christened it 'the udder'....

knighty -
could you not use flexible hose from the end of your 100mm pipe to the nozzles ? - Yes
do you know the pressure at your nozzle ? - 3.8 bar
if you do, you could work out the maximum flow rate for your pipe at that pressure... and compare that to the water you have avalible... - is there an idiot proof formula for doing this?

acresswell -
Could you find a Y-piece rather than a T-piece? - Y pieces seem to be pretty much unavailable.

camillitech -
Breastfed records? I'll need to Google that later.... 
Your manifold does look 'sharp', but if it works I may just use something similar. Interesting that you're using 32mm MDPE? as that's damn near the same bore as my 28mm copper, or is your pipe bore 32mm?  Trying to keep the cost down and just happen to have some 32mm MDPE and plenty of 28mm copper. I think it'll be fine?

Heinz

[camillitech]

Hi Heinz,

that'll be 32mm ID



though that picture is a few years old and I've replaced the green PVC with 15bar rubber as it kept bursting  I'm using 38mm ID on my Powerspout which is around 3lts/sec.

Somewhere there is a calculation in the Homepower magazine for bends, I think it's in here http://homepower.com/article/?file=HP125_pg56_Ostermeier.

Good luck, Paul

[acresswell]

acresswell -
Could you find a Y-piece rather than a T-piece? - Y pieces seem to be pretty much unavailable.

What size are you looking for?  Could you convert to flexi hose first and then split using y-pieces?  Y-pieces for flexi hose seem fairly easily available...

[Heinz]

What size are you looking for?  Could you convert to flexi hose first and then split using y-pieces?  Y-pieces for flexi hose seem fairly easily available...

Yup, could do but I think I'm going to go with the distributor cap/udder design and stick with my 32mm MDPE, 28mm copper and 25mm rubber mix of pipes. It's working OK with a 16mm nozzle on the 28mm pipe, so if I run four nozzles which are 10mm or thereabouts, the .... blo*dy hell, I hate it when that happens. Lightning and the sudden lack of phone connection, thankfully it's working again now. Weird... where was I?  If I run four nozzles @ 10mm on four bits of 28mm pipe it's an improvement over one 16mm nozzle on the 28mm pipe.

H