Experimental and Numerical Study of Hygrothermal Behaviour of a Washing Fines Hemp Test Wall

Abstract:

Bio-based materials are a promising tracks that offer thermal and environmental performances in order to reduce the consumption of energy and of non-renewable resources. For this purpose, in a previous study, the LGCGM worked on the development of Washing Fines Hemp composites (WFH) and characterized them on multiphysical points of view. Such materials show low thermal conductivity and high moisture buffer ability. In order to characterize their hygrothermal behavior at wall scale, a test wall is set up in an air-conditioned bi-climatic test room to simulate indoor and outdoor climates. This paper investigates the characterization of hygrothermal behavior of Washing Fines Hemp wall under typical Tunisian summer climate. It consists in an experimental study, supplemented by numerical simulation performed with WUFI Pro V6.5 software. The experimental hygrothermal response of the wall to such solicitations is analyzed from the temperature and relative humidity kinetics at several positions in the wall and from temperature and vapor pressure profiles. It shows that for daily cycles the two thirds of the thickness of the wall on the exterior side are active, as well regarding heat and moisture phenomena. More sorption-desorption phenomena are highlighted. The numerical results are consistent with experimental data for temperature and underestimate vapor pressure in the inner part of the wall.

• Periodical: Construction Technologies and Architecture (Volume 1)
• Pages: 195-202
• DOI: https://doi.org/10.4028/www.scientific.net/CTA.1.195
• Online since: January 2022
• Authors: Naima Boumediene*, Florence Collet, Sylvie Prétot, Lazhar Ayed, Sami Elaoud
• Keywords: Bi-Climatic Room, Experimental Study, Heat and Mass Transfer, Numerical Simulation, Washing Fines Hemp Wall, WUFI Pro Software

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