Why Does Pressure Decrease with More Outlets in a Fluid System?

In summary, the conversation discusses a situation where a positive displacement pump is producing 30gpm and there are pipe losses and a long pipe with 8 possible outlets. When one hose is attached, the pressure is P1, but when two hoses are attached, the pressure decreases to P2. The speaker is trying to explain this using the Bernoulli equation and questions why the pressure decreases. They also mention trying to calculate pipe losses in a 6mm diameter steel tube with water going through at 33m/s.
  • #1
NakorOranges
2
0
Hey, so my situation is a positive displacement pump churning out 30gpm. Theres a bunch of pipe losses that I can deal with, and then a long 1.5" pipe with 8 possible outlets (you can screw on a hose). When one hose is attached the pressure is a we will say P1 (read from a gauge on the 1.5" pipe). When two hoses are attached P2 < P1. So the pressure in the pipe goes down. This makes sense when you think about it, less pressure required to push all that liquid out since you have twice the area.

My problem is trying to explain this with the bernoulli equation. Shouldnt the energy (head or stagnation pressure if you want) in the pipe stay constant in these two situations? But since I am sure there is 30gpm going through either one hose, or 15gpm each going through 2, there is always 30gpm going through the 1.5" pipe. That means the pressure has to stay constant for the total energy to stay constant right?

Whats happening here??

Update: At this point I am of the thought the pump just pushes harder. Now I am at the stage of trying to get the pipe losses in a 6mm diameter steel tube with water going through at 33m/s. This goes past my moodly chart, and therefore the answers seem to give giant pressure drops...
 
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  • #2
Update: At this point I am of the thought the pump just pushes harder. Now I am at the stage of trying to get the pipe losses in a 6mm diameter steel tube with water going through at 33m/s. This goes past my moodly chart, and therefore the answers seem to give giant pressure drops...
 

1. What is the purpose of having multiple outlets in fluid systems?

Multiple outlets in fluid systems allow for more efficient and controlled distribution of fluids. This is especially useful in situations where a large amount of fluid needs to be distributed to multiple locations simultaneously.

2. How do multiple outlets affect the pressure and flow rate in a fluid system?

Adding multiple outlets in a fluid system can decrease the overall pressure but increase the flow rate. This is because the fluid is being distributed over a larger surface area, resulting in less pressure at each individual outlet.

3. What are the different types of multiple outlets used in fluid systems?

Some common types of multiple outlets used in fluid systems include Y-shaped outlets, T-shaped outlets, and parallel outlets. These outlets can be used to split the flow of fluids in different directions or to combine multiple flows into one.

4. How can the placement of multiple outlets affect the efficiency of a fluid system?

The placement of multiple outlets can greatly impact the efficiency of a fluid system. Placing outlets too close together can cause interference and decrease the overall flow rate, while placing them too far apart can result in uneven distribution of the fluid. It is important to carefully consider the placement of outlets for optimal efficiency.

5. What are some factors to consider when designing a fluid system with multiple outlets?

When designing a fluid system with multiple outlets, it is important to consider the type of fluid being used, the desired flow rate and pressure, the placement and size of outlets, and the overall efficiency of the system. It is also important to consider any potential safety hazards and to follow proper design and installation guidelines.

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