Multi-level simulation for dynamic analysis of domestic electric oven in forced convective heating: Evaluation and optimization of energy consumption using the brick test

In the EU, households represent 27% of final energy consumption, with electric ovens in a low-efficiency category, influencing the overall. This work describes an approach to simulating the transient thermal behaviour of an electric oven operating in forced convection, using dynamic models suitable for control design. The approach is multi-level, i.e. local heat transfer coefficients are obtained by CFD simulations, which are averaged and used by the lumped-parameter approach to obtain the time evolution of energy consumption. The CFD simulation yields the airflow and temperature velocity distribution within the cooking cavity and the overall mass and energy exchanges evaluation as a function of the cavity geometry. The heat transfer coefficients are obtained by the CFD results and integrated into the numerical-lumped parameter approach for the dynamic simulation of mass and energy exchange. This model integrates block diagrams to simulate heat transfer between nodes using a thermoelectric analogy. The cooking process follows the EN 60350-1 European standard, employing a wet brick initially cooled to 5±2 °C, placed at the oven's center, and heated until its core temperature increases by 55°C. At the end of the test, energy consumption is monitored. Evaluating the energy consumption of an electric oven is crucial for improving efficiency. In the last part of this work, a new method to reduce consumption is explained. This approach allows the integration of the two simulation levels to optimize the cooking process within the cavity. The model is validated in comparison with experiments. The results show that temperature evolution and heat fluxes obtained by the model agree with the measured ones. Efficiency improves by using correctly the heater’s power.