Numerical calculation of temperature field for the case of simple convection model in autoclave

A numerical study of temperature field for the case of 8.5-L autoclave, filled with water, is performed using the iteration method. The natural convection in liquid is assumed to be steady, axisymmetric and laminar. Two thermal steady states of the vessel are considered, with weak cooling and with intense heat exchange between the surroundings and the baffle region. For both states, almost identical local temperatures under the plunger (350°C) and under the bottom of the vessel (390°C) are achieved. The results show several common features for both thermal states. The velocity of water flow is several times higher in the upper than in the lower zone, and a strong concentration of isotherms exists in the interzone region. The radial and axial temperature gradients become greater when additional cooling is applied to the vessel