[jack2000]

Dear all,
I try to use OpenFOAM to study discharge capacity problem of a spillway. My problem is schematized as follow figure:

In this 2D problem, the upstream water level, gate opening and downstream water are known. However, the discharge capacity is unknown, so that the inlet velocity can not be given. I setup the inlet and outlet with pressure inlet/outlet boundaries.

But during the simulation, deta_T became smaller and smaller then equal 0! The simulation failed!!

for 1~2 : pressureInlet

gamma = fixedValue=1
velocity=pressureinletVelocity (I used 0)
pd=fixValue (rho*H=constant or 0, both didn't work!)

for 2~3 : pressureInlet
gamma = fixedValue=1
velocity=pressureinletVelocity (I used 0)
pd=fixValue (=0)

for 4~5 pressureOutlet
gamma= zeroGradient
velocity=zeroGradient
pd= fixedValue=0

for 5~6 pressureOutlet

gamma= zeroGradient
velocity=zeroGradient
pd= fixedValue=0


However, I can do the simulation well with velocity inlet BC
for 1~2 : Inlet
gamma = fixedValue=1
velocity=inletVelocity
pd=zeroGradient

for 2~3 : Inlet
gamma=fixedValue =0
velocity=inletVelocity=0
pd = zeroGradient

for 4~5 PresureOutlet

gamma=fixedValue =1
velocity=zeroGradient
pd=zeroGradient

for 5~6 PressureOutlet

gamma=fixedValue=0
velocity=zeroGradient
pd=zeroGradient

It is highly appreciated for any comments or suggestion!

Best Regards!

Jack

[jack2000]

I forgot to mention that I used interFoam solver.
Thanks,

Jack

[rlobosco]

Hello Jack,
I have a similar case. Can you tell me how you solve the problem?
with best regards,
rlobosco

[siamakghh2000]

it seems like it's an outdated post, yet I know the answer, so contact me in case u need.

[christianfrias]

Hi Siamak. What is the answer that you have for this problem?

Thanks!

[Akshay_11235]

I am working on a similar problem, would be great if you could share the boundary conditions for U, p_rgh and alpha.water for this particular case. Thank You!