Simulation of steel coil heat transfer in HPH furnace

The mathematical model has been established for the simulation of steel coil's heat transfer during annealing thermal process in HPH (high performance hydrogen) furnace. The equivalent radial thermal conductivity is adopted by statistical analysis regression approach through the combination of a large quantity of production data collected in practice and theoretical analyses. The effect of the number of coils on circulating flow gas is considered for calculating the convection heat transfer coefficient. The temperature within the coil is predicted with the developed model during the annealing cycle including heating process and cooling process. The good consistency between the predicted results and the experimental data has demonstrated that the mathematical model established and the parameters identified by this paper are scientifically feasible and the effective method of calculation for coil equivalent radial heat transfer coefficient and circulating gas flow has been identified successfully, which largely enhances the operability and feasibility of the mathematic model. This model provides a theoretical basis and an effective means to conduct studies on the impact that foresaid factors may imposed on the steel coil's temperature field, to analyze the stress within coils, to realize online control and optimal production and to increase facility output by increasing heating and cooling rates of coils without producing higher thermal stress.