Hi,
Would the inlet pressure to this pump be 5 Bar? and if I was to close the ball valve after the pump (deadhead it) would it ramp it up to 10 bar as the deadhead pressure is 5 bar?
Itsmoked, thanks for the response.
How would you change this set up? We need to do something to create a pressure differential in the bypass line or else no flow would go around the loop? Would you agree? It would just flow through the main line.
What would be the inlet pressure to the pump...
The pump doesn't have a differential head of 4-5 bar, it just dead heads at that pressure. it was sized to pump against a pressure of 2-4 bar (what the line pressure was thought to be). It is effectively a recirc pump, which always tend to be centrifugal. It's never occurred to me to use a PD...
Thanks but does that mean the bigger the frictional loss in the restriction, the bigger the pressure on the inlet to the restriction like:
Bernoulli stuff 1 + frictional loss 1 (before restriction) = Bernoulli stuff 2 + frictional loss 2 (after restriciton) - if frictional loss stays the same...
Hi,
Yes, I know the relationship between pressure and flow for a centrifugal pump but this isn't quite what I mean. Bernoulli's equation teaches us that you don't increase the pressure as a result of increasing the restriction on the outflow, it states that the pressure will reduce and velocity...
Hi,
Can someone please assist? If I have a pump with a pressure gauge, followed by a diaphragm valve on the discharge side and I start to throttle the flow with the diaphragm valve, why does the pressure start to increase and therefore flow decrease? If you narrow a pipe, wouldn't Bernoulli's...
Hi,
I'm thinking if I had a pump that was pumping say 20m3/hr through a 4" pipe, i then implement some sort of restriction so that the pipe is now 2" at some point. My thinking is that the flow would remain 20 m3/hr at every point in the line because of the continuity equation and the pressure...
Hi,
I'm hoping someone can help me. According to Bernoulli's principle, when water is flowing through a pipe and the pipe restricts in some way, the velocity increases/pressure decreases through the restriction and then ramps back up to the velocity and pressure it was originally at once it...
Hi,
Thanks for the response. Here is a diagram of the installation. We needed the pump for forcing the water around the bypass loop as we weren't able to install anything in the main line to force it around the bypass loop like an orifice plate or valve to restrict. PS I never designed the...
Hi,
Thanks for the responses. The pump is a single stage centrifugal pump. The pump is installed in a bypass loop I.e a pipe is branched from the main line, which then goes back into the main line. The pump is installed in the branched line. The water is pumped through the bypass and back round...
Hi,
Could someone please tell me if a pump can exceed it's dead head pressure? i.e. if a pump has a dead head pressure of 4 bar but the pressure coming into the pump is 7 bar, would the pump ramp up the pressure to 11 bar?
