TY - JOUR TI - Effect of Prandtl number on heat transfer characteristics in an axisymmetric sudden expansion: A numerical study AU - Alammar Khalid N JN - Thermal Science PY - 2007 VL - 11 IS - 4 SP - 171 EP - 178 PT - Article AB - Using the standard k-e turbulence model, an incompressible, axisymmetric turbulent flow with a sudden expansion was simulated. Effect of Prandtl number on heat transfer characteristics downstream of the expansion was investigated. The simulation revealed circulation downstream of the expansion. A secondary circulation (corner eddy) was also predicted. Reattachment was predicted at approximately 10 step heights. Corresponding to Prandtl number of 7.0, a peak Nusselt number 13 times the fully-developed value was predicted. The ratio of peak to fully-developed Nusselt number was shown to decrease with decreasing Prandtl number. Location of maximum Nusselt number was insensitive to Prandtl number.