Further Results on the Heat Transfer to Low-Prandtl Number Fluids in Pipes

Numerical predictions have been made of heat transfer to low-Prandtl-number fluids in pipes with constant wall heat flux. The turbulence model employed is of the two-equation (k-)c kind in the core and the one-equation (k) kind in the near-wall region. Fluids with Prandtl numbers in the range 0.007-0.045 have been examined, in the Reynolds range from 7600 to 106. Temperature profiles and Nusselt numbers are in fairly good agreement with experiments on fully developed flow. Nusselt numbers for the thermal entrance region are found to be in reasonable agreement with the experimental results, which, however, display a large scatter