Hi,

I am doing a calculation with a precursor channel that calculates a developed flow. Then,I apply the profile to a channel where the real calculation takes place. The channel considered are at the moment planar rectangular channels. The developed velocity profile should not evolve in the channel if it has the same height as the precursor channel. However, I get singularities of increased pressure near the entry point ( http://img229.imageshack.us/img229/1359/planap5.jpg ), at the wall, which in turn modify the wall shear stress ( http://img73.imageshack.us/img73/20/shearkn0.jpg ) (and then the heat transfer is modified). As a result, it makes the developed profile unusable, because it as to redevelop itself in the following channel, and thus I have to 'spend' a lot of cells after the entry just to recover the physical profile. I am using the k-omega SST low Reynolds viscous model (here is the y+ profile http://img229.imageshack.us/img229/9279/wallyje3.jpg), and my Reynolds number using the hydraulic diameter and mean velocity is Re=11200, but the same problem appeared for laminar flows.

I would like to know if anybody has encountered a similar problem, and is able to help,

Thanks

VK

It appears that in my periodical calculation, for an unknown reason, at the periodical boundary the pressure had singularities (pressure was not constant in the section). Thus the corresponding profile did not correspond to a developed profile, and had to be redeveloped in the following non periodical channel.