This paper deals with a numerical solution of conduction and convection heat transfer in a partially filled horizontal cylinder. A mixed boundary condition is applied to the surface. The ambient temperature is assumed to vary sinusoidally in time, representing the diurnal variation experienced in the natural environment. The heat transfer coefficients on the external surface of the tank and the liquid free surface are assumed to be different, with the free surface being more insulated. Multiple eddies and flow reversals are found to occur because of the fluctuating ambient temperature. These lead to much higher core region temperatures than predicted by the conduction solution. The free surface temperature is also higher with convection present, and is found to be quite sensitive to the free surface heat transfer coefficient. In the design of relief devices for such partially filled tanks, therefore, simple lumped heat balance or conduction solutions will not suffice to estimate the liquid's mean temperature.
|Original language||English (US)|
|Title of host publication||American Institute of Chemical Engineers, National Meeting|
|State||Published - 1986|