Influence on Convection Heat Transfer of Unsteady Flow in a Tube

Turbulent convection heat transfer with monotonously time-increasing mass flux in a tube with consideration of variable thermophysical properties was investigated numerically. The turbulent heat transfer model was based on the equation of eddy shear stress and for unsteady process. The numerical calculations were compared with experimental data. It is shown that the basic features of the processes discussed in the present paper are the same as for the fluids with constant properties investigated earlier. However variable thermophysical properties increase the transient effects especially at high temperature factors.