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JuanC97
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Some days ago I got confused trying to solve an exercise about fluid dynamics. Trying to simplify the problem here is a similar situation:
I have a cistern connected to a tube containing a fluid as shown in the picture below.
Assumming that the fluid is incompressible...
I know from the law of continuity that every single point in the same area has to move with the same speed.
However, Bernoulli's equation applied to the point B says that:
P atm + rho*g*h = Patm + (1/2)*rho*V2
This implies that v = ( 2gh )1/2. but... in the point C it will be v = ( 2g(h+d) )1/2.
That means that every single point has a different speed despite being in the same cross-sectional area.
What's the right equation?. Am I doing something wrong?. Where's the mistake?
PD: Both sides are open and it is supposed that the velocity of every "control volume" inside the cistern tends to zero.
I have a cistern connected to a tube containing a fluid as shown in the picture below.
Assumming that the fluid is incompressible...
I know from the law of continuity that every single point in the same area has to move with the same speed.
However, Bernoulli's equation applied to the point B says that:
P atm + rho*g*h = Patm + (1/2)*rho*V2
This implies that v = ( 2gh )1/2. but... in the point C it will be v = ( 2g(h+d) )1/2.
That means that every single point has a different speed despite being in the same cross-sectional area.
What's the right equation?. Am I doing something wrong?. Where's the mistake?
PD: Both sides are open and it is supposed that the velocity of every "control volume" inside the cistern tends to zero.
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