In this paper, momentum and heat transfer equation was solved numerically to study axially forced convection heat transfer characteristics in rod bundle arrays by use of non-orthogonal coordinates.
Heat transfer equation was solved three dimensionally in case of Pr=3.0, fully developed flow and temperature independent properties.
For turbulent flow calculations, one-equation turbulence model was applied to find the features of fully developed turbulent flow through infinite equilateral triangular or rectangular array.
The calculated value of dimensionless velocity and wall shear stress distributions were shown to be in good agreement with published experimental data.
The eddy diffusivity of heat was calculated by use turbulent prandtl number through the von-karman correlation.
And thus in laminar and turbulent flow, the effect of Reynolds number and P/D (pitch to diameter ratio) for Nusselt number distribution was studied in the uniform wall temperature boundary condition and uniform heat flux condition.
For fully established temperature field, the variation of Nusselt number could be disregarded for P/D 1.5 and for P/D 1.3 in turbulent flow and the effect of boundary condition on Nusselt number distribution was very small.
In turbulent flow, Nusselt number was proportional to Reynolds number by the power of 0.83 which is slightly larger than the value of the power in the Dittus Boelter's correlation 0.8.