[rajan19us]

Dear openFOAMers,

I am trying to build a case where I want to simulate internal flow through an applicator. I only have 'pressure inlet' and 'pressure outlet' values.

So, at outlet the B.c. will look like p = 0 and velocity as 'zero gradient'.

The problem is regarding the inlet B.C. The geometry is complex shaped so that I can't calculate the exact value of velocity/flow rate using the available pressure value.

Thus, at inlet,
for p,
type fixedValue;
value uniform 3600;

for U,

1) which B.C. am I supposed to use?

2) Is it really possible to get decent results using fixed pressure conditions at
both inlet and outlet??
3) If not, how should this kind of problem be approached?

I would be grateful if anyone could shed some light on this topic. Thanks in advance.

Regards,
Rajan

[piu58]

It is very critical to use pressure at the inlet and at the outlet. It may be that you know these values form measurements, but the pressure loss depends on the geometry and the flow, which is to be calculated.
If there is a discrpancy (and normally it is) you may have an flow which is accelerated in evnery time step and blows up eventual.

I recommend to use a velocity input and change the velocity until the pressure drop is the one measured.

[rajan19us]

@piu58 Thanks for the apt answer. That was really helpful.

Regards,
Rajan