Numerical simulation of heat transfer in loaded heat treatment furnaces

Abstract
Heat transfer simulation within heat treatment furnaces is of great significance for the prediction and control of the ultimate microstructure, properties and dimensional stability of the workpieces and even the performance of furnaces. In this paper a set of models is proposed to solve heat transfer problems in a loaded furnace, including radiation, convection and conduction. Furthermore, a 3-dimensional algorithm based on finite difference method (FDM) is presented with a complete system for process simulation system. In the radiation module, view factor is calculated by direct integral method for all element pairs exposed to each other based on the blocking judgment. Combustion in gas-fired furnace and PID control are also included in the furnace model. The heat transfer models are integrated with furnace model to simulate the heating process of workpieces. Temperature distribution in workpiece and its variation with time are predicted by the system. An experiment is carried out for the validation of the system.