MODELING, SIMULATION, AND VALIDATION OF AN ELECTRIC HEATER MODEL OPERATING IN THE TRANSIENT REGIME

Resumo

A dynamic model for an electric air heater operating in the transient regime was developed from an energy balance in the heater, taking into account the energy supplied to the system by the electric resistances, the energy lost to the surroundings by convection, and the accumulation of energy in the system. The resulting model was represented by an ordinary differential equation of the first order with two parameters to be determined. The model parameters were adjusted by the least squares method. The experimental temperature measurements used to validate the model were obtained at the heater outlet after different disturbances in the electric heater temperature through changes in the voltage applied to the heater and waiting for the system to reach steady state condition. The results revealed that the model adequately represented the behavior of the system in both transient and permanent regimes and showed that this model can be used for the simulation, analysis, and design of electric heaters.