LittleInch's understanding of the BPT is correct.
This is a new structure on the pipeline and the pipe after the tank is replaced with a large diameter pipe.
Once I get my numbers in order I'll be happy the pipe size if OK, my impression is that it is but I can't quite get there...yet!
I'm confident that air will not enter the system via the BPT for a few reasons:
The geometry (likely something like 5m long x 2m wide x 2 m high) will provide enough...
Thanks I'll look into this some more, I've now labelled the schematic showing Point A and B, I have also labelled the pipe sections of interest as Point 1 and 2 to aid discussions.
You are correct regarding air entrainment, we do know we will see entrained air from the main intake as the chamber is relatively small considering the stilling time required to allow the air to come out of suspension. We have isolated intake 2 for some time now and there are no air entrainment...
Thanks, that certainly makes the flow rate look good. I'm curious as to why this is added to Point A? As it's a headloss I had thought it would be subtracted from Point A.
The method you suggest shows that the BPT should be at a higher elevation than initially thought to provide the flow into...
Hi,
Thanks for the responses so far, very helpful.
I've attached my workings in Excel which should hopefully be easy and quick to follow.
Point B (where the pipe from the BPT connects to the penstock) has been modelled by subtracting the headloss of the pipe between the main intake and where...
That's exactly what I thought, the pipe is too small. I've even tried modelling with a smoother pipe material but that doesn't help.
The normal flow is 0.413m3/s, sometimes it might increase to 0.65m3/s but unlikely.
I also think the short length of pipe, 30m, doesn't help but this can't...
I'm reviewing a modification to a multi-intake hydro power scheme and have attempted to do some check calculations myself which aren't working out.
Summary
There is a main intake which feeds a penstock to the power station.
Two secondary intakes discharge water into the penstock.
The second...
