Thermal characterization of a high-temperature industrial bread-baking oven: A comprehensive experimental and numerical study

This study presents a complete experimental campaign and the first three-dimensional numerical model developed for a high-temperature bread-baking oven. A typical baking tunnel oven prototype is designed and constructed for the study. The prototype has appropriate temperature sensors to investigate temperature profiles at several points inside the baking chamber. A specific device is developed to measure the heat flux received by bread during baking, showing values ranging between 6.6 and 29.3 kW/m2. Computational fluid dynamic software models the non-premixed combustion of diesel fuel occurring at the burner and the airflow characteristics inside the baking chamber. Numerical results show the heterogeneity of temperatures (450-1000 degrees C) inside the tunnel oven and agree with the experimentally measured values (maximal variation of 9 %) also shows complex airflow dynamics and the existence of multiple velocity zones. The model is applied to the specific case of Lebanese bread baking. An energy efficiency analysis of the oven reveals an efficiency range of around 16 %. This foundational work sets the stage for future research and optimization of oven design, energy recovery systems, and bread-baking processes. Also, the insights gained from this study will be integral in developing future numerical models for flatbread baking coupled with large deformation.