Direct numerical simulation of turbulent forced convection in a pipe

Direct numerical simulations (DNS) are carried out to study fully developed turbulent pipe flow and heat transfer at Reynolds number Rem ≈ 5300 based on bulk velocity and pipe diameter. This paper provides detailed information on the mean properties and turbulence statistics up to fourth order, the budget and the wavenumber spectra of the temperature fluctuations, for three different wall boundary conditions. To investigate the differences between fully developed turbulent heat transfer in axisymmetric pipe and plane channel geometry, the present DNS results are compared to those obtained from channel flow simulations. The differences between channel and pipe flow statistics are modest and reveal that the temperature fluctuations in the pipe are slightly more intense. The present results show that the mean temperature profile does not conform to the accepted law of the wall. The boundary conditions affect the turbulence statistics both in the near-wall and core regions; this observation complements previous studies concerning different flow and heat transfer configurations.