[Santiago]

Hi all,

I've been struggling a bit to get the right results using Extend's version of interFoam. In general, I cannot get the right discharge of a pipe flow driven by gravity

I have prepared a very simple version of my problem: pipe flow between two tanks. The pipe diameter is 1 m, lenght is ~72 m, the upstream head is 3.561 m and the downstream head is of 3.4 m. Assuming a smooth pipe, by using Bernoulli + Colebrook-White one gets that the discharge is around 1.2 cu.m/s.

If I go and set the case in FOAM-extend, I get a discharge of ~206 lt/s (!!), as shown in the figure below.

https://imgur.com/vXPxaNF

Running the exact same case (same BCs) in OpenFOAM v.4, gives me a discharge of 1.05 cu.m/s. For this I don't have a figure 'cause I couldn't make codeStreams to work in this version (see attached files)

I have tarred the cases I ran using FOAM-extend, and the one of OpenFOAM. You can download them here:

https://we.tl/t-SCwqNyZG5u

I would really appreciate some input on this, since I cannot see any noticeable difference neither between the algorithms, except on how the pressure is called (pd vs. p_rgh), nor on the cases' setup.

Thanks