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arXiv · 2203.07032

Thermal circuits assembling and state-space extraction for modelling heat transfer in buildings

Christian Ghiaus·Naveed Ahmad
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Abstract

State-space representation is essential in the theory of dynamic systems. This paper introduces a methodology for obtaining state-space representation from the thermal models of elementary components of a building by the conjunction of two methods: 1) assembling of thermal circuits and 2) state-space extraction from thermal circuit. These methods are fully illustrated on a very simple model and tested on a real house of about 100 m 2 on which detailed measurements were achieved for 40 days at a time step of 10 min. The errors obtained between the measurements and the simulation results are in the order of $\pm$1 {\textdegree}C for a single zone and $\pm$2 {\textdegree}C for seven thermal zones. Besides simulation, parameter identification and control, the methods for assembling thermal circuits and extraction of state-space representation may be useful in Building Information Modelling (BIM).

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Christian Ghiaus, Naveed Ahmad. 2022-03-08. Thermal circuits assembling and state-space extraction for modelling heat transfer in buildings. https://doi.org/10.1016/j.energy.2020.117019

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