I've been struggling with a school project for some time now.
I need to find out the speed at wich a tank is draining to make a model out of it (in simulink). The model will show a x-t graph, x being the height of the water in the tank.
The flow is laminar, but the lenght of the exittube is significant enough to enduce friciton.
A basic model that i made can already account for the diameter of the exittube, but not yet for it's lenght (and thus friction).
When i tried implementing formulas for head loss the model didn't work as i had hoped. I think i might be using the wrong (combinations) of formulas.
I hope someone can help me with finding out the problem i'm facing here. In calculating the speed of the waterlevel i used the following formulas:
- Bernoulli's equation (with head loss added on the right side of the equation)
- Head loss = f*L/D*(vaverage/2g)
- Friction factor = 64/Re
- Re = (density*vaverage*diameter)/viscosity
- vaverage = (dP*D^2)/(32*viscosity*L)
Thank you kindly for your response.
Edited by Student2001, 16 February 2020 - 01:52 PM.