[petarcrncec]

Hi,
I'm doing a simulation in Fluent where i have both fluid and solid zones. The solid zone is very thin compared to the fluid, and it serves as a heat conductor between the two fluid zones. The problem I'm having is that when i supress the solid bodies, Fluent creates standard no slip walls on the boundaries of fluid zones and simulation runs well, so no problems there. Once I turn on these solid zones, the simulation (residuals) starts fluctuating and it takes it much longer to converge, and it even diverges if underelaxation factors are not lowered. Now, i understand that temperature can affect the flow of the fluid, but I find it odd that even without heat transfer (no energy equation) this behaviour persists. So my question is, is there any way of having a normal simulation with these shadow walls, and why is there even a difference between standard and shadow walls, if they seem to serve the same purpose when no heat is being transfered. Thanks!