hi, 

We are new to the both solidworks and forum, so if this entry is not proper, sorry in advance  

we try to simulate air flow caused by pressure difference in vent, we have calculated airflow in the brochure. 

So we try to do it but cant come close to values in brochure

our aprroach is;

(Both of these tries done in internal flow analysis) 

1-) We created static pressure on exterior surface [1] (101325 Pa) same as initial pressure.

2-) For natural flow, we created enviromental/static pressure (we tried both separately) interior surface [2] . (101317 Pa)

and we used 2.5 million cells (meshing does not make any significant difference)

In both of these steps we created LID for each gaps (as shown in pic-2) and give boundary condition on their surfaces.

Problem

We are getting wrong results, almost two times more than it should be. 

We couldnt understand why this is happening , can anyone give us hand on this ? 

pic-1

pic-2

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