Convergence troubles with 3D heat exchanger simula

Balcazar - Capetillo

Hi everybody!

We are working in a 3D compact heat exchanger simulation (air - air) in Fluent. we have two rectangular ducts and between them some triangular fins. Inside rectangular ducts we set hot air (velocity, mass flow, pressure, temperature known) and over the fins flows cooling air (temperature and velocity known). We have serious converging problems, the residuals behavior is very rare. Do someone could advice us about initialization conditions and/or 3D models?

Thank you very much