Modelling simulation and validation of duct air heating system

The paper develops a mathematical model of duct air heating process, as widely used in drying of different materials in the form of powder. In this work, a mathematical model of the duct air heating system containing resistive heating element has been developed for simulation study, by considering one dimensional forced convective heat transport phenomena. Then a Continuous Time (CT) model identification technique based on Instrumental Variation (IV) approach has been applied to the actual duct air heating process, in order to identify the model parameters. The model was intended to evaluate dynamic changes in outlet air temperature corresponds to changes in current through the heating coils, air flow velocity and ambient temperature. The proposed mathematical model has been validated by a set of simulated models obtained from the experimental data collected from the actual setup, involving duct air heating under open loop conditions. The obtained responses of the mathematical model as well as identified system were found to be closely correlated with the experimental responses.