Master's thesis and Internship : Thermal modelling and experimental measures of a French-type masonry stove for Low-Tech heating applications

Abstract

This thesis supports the Renolow project of the non-profit organisation LowTech Liège, which promotes low-tech renovation strategies, by focusing on a French-type masonry stove used for household heating. To help the association in their goal of spreading this heating system, a transient numerical model of the stove’s thermal behaviour is developed. This model can be used by LowTech Liège as a tool to evaluate temperature evolution, thermal comfort, and energy use quantitatively.

The numerical model is implemented in Python and relies on a discretised representation of the stove. The model is separated in two parts: a representation of the time-varying heat released by batch wood combustion, and the heat transfer processes described through a resistance–capacitance (RC) network. Experimental temperature measurements from two test campaigns are used both to explore model parameters and to assess the validity of the simulations.

The comparison with experimental data shows that the model captures the main transient thermal behaviour of the masonry stove, with simulated temperature profiles closely matching the experimental trends. The absolute root means square error, between simulated and experimental external wall surface temperatures is approximately 8 °C, corresponding to a mean absolute error of about 6.5 °C. Given the experimental uncertainties, the external surface temperatures ranging from 20 °C to about 130 °C, and the modelling assumptions, this level of agreement is considered satisfactory for a first-generation numerical model and provides a solid basis for further research and future thermal comfort and energy performance assessments.