• Support PF! Buy your school textbooks, materials and every day products Here!

Flow in branch pipe

  • Thread starter foo9008
  • Start date
  • #1
678
4

Homework Statement


in the notes , the author stated that the water from reservoir 1 could flow to reservoir 2 and 3 ..... i dont understand how could the water flow from 1 to 2 through junction D ? how could the water flow from low to high ?
OrulDXM.png


Homework Equations




The Attempt at a Solution

 

Answers and Replies

  • #2
BvU
Science Advisor
Homework Helper
2019 Award
13,043
3,019
Now my response went into the black hole :cry:

Don't see no D !

And water flows under the driving force we call pressure ! As long as pa > pb it will flow, up or down or sideways from a to b - as long as there is a path!
 
Last edited:
  • #3
678
4
Now my response went into the black hole :cry:

Don't see no D !

And water flows under the driving force we call pressure ! As long as pa > pb it will flow, up or down or sideways - as long as there is a path!
do you mean as long as position reservoir A > B , the pressure is large enough for the water to flow upwards?
 
  • #4
BvU
Science Advisor
Homework Helper
2019 Award
13,043
3,019
It's a bit more complicated than that because of the presence of reservoir 3.
It's not the position that 'decides', but the pressure.
From the picture I'd conclude that ##H_J > h_{f2}## is the condition for flow towards the second reservoir. For instance if pipe 3 is very narrow.
 
  • #5
678
4
It's a bit more complicated than that because of the presence of reservoir 3.
It's not the position that 'decides', but the pressure.
From the picture I'd conclude that ##H_J > h_{f2}## is the condition for flow towards the second reservoir. For instance if pipe 3 is very narrow.
##H_J ? what do you mean by it ?
 
  • #6
678
4
It's a bit more complicated than that because of the presence of reservoir 3.
It's not the position that 'decides', but the pressure.
From the picture I'd conclude that ##H_J > h_{f2}## is the condition for flow towards the second reservoir. For instance if pipe 3 is very narrow.
how to know that if P at A > P at B ?
 
  • #7
BvU
Science Advisor
Homework Helper
2019 Award
13,043
3,019
how to know that if P at A > P at B ?
That's exactly what they try to teach you with the picture !
##H_J## is the total head at J (what you called D, the branching point). Since that depends on the flows and the flows depend on the head differences, they propose an iterative solution method.
 
  • #8
678
4
That's exactly what they try to teach you with the picture !
##H_J## is the total head at J (what you called D, the branching point). Since that depends on the flows and the flows depend on the head differences, they propose an iterative solution method.
ok , can i also say it as position of A is the highest , so P/( rho g ) + z has the highest value for A ?
 
  • #9
678
4
That's exactly what they try to teach you with the picture !
##H_J## is the total head at J (what you called D, the branching point). Since that depends on the flows and the flows depend on the head differences, they propose an iterative solution method.
i dont understand how could the water flow from q to 3 and Q2 is 0 ?
 

Related Threads on Flow in branch pipe

  • Last Post
Replies
7
Views
698
  • Last Post
Replies
21
Views
1K
  • Last Post
Replies
15
Views
572
  • Last Post
Replies
9
Views
594
Replies
13
Views
382
  • Last Post
Replies
0
Views
5K
  • Last Post
Replies
5
Views
4K
  • Last Post
Replies
3
Views
346
  • Last Post
Replies
6
Views
7K
  • Last Post
Replies
2
Views
2K
Top