THERMAL SCIENCE

International Scientific Journal

Daniel Risberg

,

Lars B. Westerlund

,

J. Gunnar I. Hellström

COMPUTATIONAL FLUID DYNAMICS SIMULATION OF INDOOR CLIMATE IN LOW ENERGY BUILDINGS: COMPUTATIONAL SET UP

ABSTRACT
In this paper CFD was used for simulation of the indoor climate in a part of a low energy building. The focus of the work was on investigating the computational set up, such as grid size and boundary conditions in order to solve the indoor climate problems in an accurate way. Future work is to model a complete building, with reasonable calculation time and accuracy. A limited number of grid elements and knowledge of boundary settings are therefore essential. An accurate grid edge size of around 0.1 m was enough to predict the climate according to a grid independency study. Different turbulence models were compared with only small differences in the indoor air velocities and temperatures. The models show that radiation between building surfaces has a large impact on the temperature field inside the building, with the largest differences at the floor level. Simplifying the simulations by modelling the radiator as a surface in the outer wall of the room is appropriate for the calculations. The overall indoor climate is finally compared between three different cases for the outdoor air temperature. The results show a good indoor climate for a low energy building all around the year.
KEYWORDS
CFD-simulation, computational setup, indoor climate, low energy buildings, turbulence models, grid size, radiation, convection, radiator, near wall treatment
PAPER SUBMITTED: 2015-06-04
PAPER REVISED: 2015-10-15
PAPER ACCEPTED: 2015-10-15
PUBLISHED ONLINE: 2015-11-15
DOI REFERENCE: https://doi.org/10.2298/TSCI150604167R
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2017, VOLUME 21, ISSUE Issue 5, PAGES [1985 - 1998]
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Computational fluid dynamics simulation of indoor climate in low energy buildings: Computational set up

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