Understanding forces acting on a pipe bend when fluid is passing through

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I am trying to understand the forces that are acting on a pipe bend when a fluid is passing through it.
Hello all I am trying to understand the forces that are acting on a pipe bend when a fluid is passing through it.

I have been given the following diagram:-

Diagram of fluid flowing through a pipe bend: horizontal inlet with P1A1 and velocity v1, bending up at angle θ to outlet with velocity v2, and force arrows P2A2, P2A2 Sin θ and P2A2 Cos θ acting on the bend's outlet section.


The bit i cannot get my head around is why does P2A2 point the way it does i.e. down towards the left shouldn't is point the opposite direction i.e up right?

The reason why i say that the arrow direction is opposite is because the fluid is flowing in that direction?

Can someone explain?

Thank you.
 
The force on A2 shown is the force acting on the fluid in the control volume exerted by the fluid downstream of the exit cross section.
 
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What force makes the fluid move in that direction, assuming the cross area remains the same?
 
Lnewqban said:
What force makes the fluid move in that direction, assuming the cross area remains the same?
The force of the pipe bend on the fluid and (of course) the forward pressure force at the entrance.