Wall-wall shadow

Ness

Hi!

I have read in the fluent documentation that when a wall BC has got fluid at the both sides, it is automatically created a shadow zone.

The fact is that I'm running a simulation over flat disk but the typical value of Cd 1.17 is not appearing. Cd over the disk is 0.7 aprox. and, over the shadow, 0.8. So summing up this terms 1.5. I don´t get the 1.17 right value.

Why do I get different results for the shadow? Have the shadow got influence in the case? What may I be doing bad?

I think this case is known enough so you got any suggestion.

THanks in advance!