Paper Conference

Proceedings of Building Simulation 2017: 15th Conference of IBPSA


Analysis of the (Urban) Microclimate Effects on the Building Energy Behaviour

Lucie Merlier1,2, Lo¨ıc Frayssinet1,2, Fre´de´ric Kuznik1,2, Gilles Rusaoue¨n2, Ke´vyn Johannes1,2, Jean-Luc Hubert1,3, Maya Milliez1,3
1BHEE High Energy Efficiency Buildings, joint laboratory CETHIL / EDF, France
2Univ Lyon, INSA de Lyon, Universite´ Lyon 1, CNRS,UMR 5008 CETHIL, F-69621Villeurbanne Cedex, France
3EDF R.& D. – EnerBaT, F-77818 Moreˆt-sur-Loing Cedex, France.

Abstract: As a first but critical step toward integrated energy simulations of urban buildings, this exploratory study develops a methodology aiming at modelling the local thermo-aeraulic environment of buildings and studying the relative effects of radiative, convective, thermal and pressure conditions on their thermal behaviour. For this purpose, detailed microclimatic and building energy models are used, namely SOLENE-microclimat and BuildSysPro. This study more specifically addresses summer conditions and a thermally inefficient building given global warming challenges, urban heat island problems and the eledering building stock of European cities. As a basis for further applied studies and in order to basically highlight the effect of each above-mentioned environmental factor, this study focuses on generic tests cases: an isolated cubic building and the same building located in a theoretical urban environment. For the considered building, results show that: • even considering an isolated building, taking into account in details an open but mineral environment instead of outdoor conditions derived from typical weather files (except for short wave radiation fluxes) may modify results by 1.3 ◦C, mainly because of long-wave radiative exchanges; • assuming no general urban heat island effect, direct effects of urban environment may decrease indoor air temperatures by 0.15 ◦C on average, mainly resulting from complex compensations between short and long wave radiative heat transfers as well as aeraulics. Beside, aeraulic boundary conditions are very impacted on by surrounding buildings, which is challenging for natural ventilation issues -including free cooling- especially when further considering energy efficient buildings.
Pages: 1780 - 1787