Brain fade/idiot moment - simple question about pipe flows

In summary: This is because the flow dynamics on the suction side are more complex and harder to predict/control compared to the discharge side. There are also practical considerations such as access for maintenance and control of noise/vibration.In summary, the location of the butterfly valve in relation to the fan depends on the specific purpose and design of the system. However, in general, it is more common to have the valve downstream of the fan in order to better control the flow dynamics and for practical considerations. More information about the purpose of the fan and the wider system is needed to give a more accurate answer.
  • #1
alpha754293
29
1
Stupid question:

I have the following pipe configuration:

Working fluid = ambient air

Pipe1 = 6 inch ID x 24 inch length
Expansion1 = 2 inch length
Pipe2 = 8 inch ID x 2 inch length
Fan1 = assume 200 CFM @ 2860 rpm, 0.05 inH2O
Contraction1 = 2 inch length
Pipe3 = 6 inch ID x 12 inch length
Butterfly valve, 50% open
Pipe4 = 6 inch ID x 12 inch length

Question:

Does it matter whether the butterfly valve is downstream of the fan or upstream of the fan?

(e.g. Pipe1 --> Expansion1 --> Pipe2 --> Fan1 --> Contraction1 --> Pipe3 --> Butterfly valve --> Pipe4

Or

Pipe1 --> Butterfly valve --> Expansion1 --> Pipe2 --> Fan1 --> Contraction1 --> Pipe3 --> Pipe4)

Discuss/prove your work/answer please.

(I tried modelling it with a 1D pipe flow program and I don't know if I am doing it right. And before I go and spend a significantly longer amount of time building the 3D model, I would like to know what the expected value should be for a problem like this. Thanks.)
 
Last edited by a moderator:
Engineering news on Phys.org
  • #2
alpha754293 said:
Discuss/prove your work/answer please.
This looks like schoolwork. Should I move it to the schoolwork forums for you?
 
  • #3
berkeman said:
This looks like schoolwork. Should I move it to the schoolwork forums for you?

It looks like it's schoolwork, but it actually isn't.

It's professional work.

(Background: I'm doing CFD with turbomachinery and we are having some problems with the test results so I wanted to quickly model it with 1D pipe flow program and failed to do so, and I wanted to see if there was a way to quickly come up with the answer before I go spending a lot of time building the 3D CFD model to test for the same thing.)

Thanks.

Like I said - idiot/brain fade.
 
  • Like
Likes berkeman
  • #4
It is impossible to give a 'correct' answer without knowing what the purpose of the fan is in the context of the wider system. That said, from my experience (process engineer) it is far more common to control rotating equipment such as fans with backpressure (i.e. valve downstream) rather than on the suction side.
 

1. What causes brain fade or an idiot moment?

Brain fade or an idiot moment is caused by a temporary lapse in cognitive functioning. This can be due to fatigue, stress, distractions, or simply not being fully engaged in the task at hand.

2. How does brain fade affect our ability to solve simple problems?

When experiencing brain fade, our ability to think critically and solve problems is impaired. This can lead to making mistakes or struggling to find solutions to even simple problems.

3. Can brain fade be prevented?

While brain fade cannot be completely prevented, there are steps that can be taken to reduce its occurrence. These include practicing mindfulness, getting enough rest and sleep, and minimizing distractions while working on complex tasks.

4. Is brain fade a sign of a larger issue?

In most cases, brain fade is a normal and temporary occurrence. However, if brain fade becomes a frequent and persistent issue, it may be a sign of a larger underlying problem such as stress, sleep deprivation, or a medical condition. It is important to seek medical advice if brain fade is affecting daily functioning.

5. How can we recover from a brain fade or idiot moment?

The best way to recover from a brain fade or idiot moment is to take a break and allow your mind to rest and recharge. Engage in an activity that you enjoy, take a walk, or practice deep breathing. This can help clear your mind and allow you to come back to the task with a fresh perspective.

Similar threads

Air line gauge in a T fitting, error vs flow
    • General Engineering
Replies
1
Views
3K
Exhaust and engine accoustics for asthetics and performance
    • General Engineering
Replies
2
Views
6K

Hot Threads

Recent Insights

Back
Top