Phase Change Materials(PCMs)have high thermal inertia,and hemp concrete(HC),a bio-based concrete,has strong hygroscopic behavior.In previous studies,PCM has been extensively combined with many materials,however,most o...Phase Change Materials(PCMs)have high thermal inertia,and hemp concrete(HC),a bio-based concrete,has strong hygroscopic behavior.In previous studies,PCM has been extensively combined with many materials,however,most of these studies focused on thermal properties while neglecting hygroscopic aspects.In this study,the two materials have been combined into a building envelope and the related hygrothermal properties have been studied.In particular,numerical studies have been performed to investigate the temperature and relative humidity behavior inside the HC,and the effect of adding PCM on the hygrothermal behavior of the HC.The results show that there is a high coupling between temperature and relative humidity inside the HC,since the relative humidity changes on the second and third days are different,with values of 8%and 4%,respectively.Also,the variation of relative humidity with temperature indicates the dominant influence of temperature on relative humidity variation.With the presence of PCM,the temperature variation inside the HC is damped due to the high thermal inertia of the PCM,which also leads to suppression of moisture evaporation and thus damping of relative humidity variation.On the second and third days,the temperature changes at the central position are reduced by 4.6%and 5.1%,compared to the quarter position.For the relative humidity change,the reductions are 5.3%and 5.4%on the second and third days,respectively.Therefore,PCM,with high thermal inertia,acts as a temperature damper and has the potential to increase the moisture buffering capacity inside the HC.This makes it possible for such a combined envelope to have both thermal and hygric inertia.展开更多
This paper deals with the experimental investigation of hygrothermal behavior of wooden-frame building enve-lope.The experiment was based on in-situ monitoring of a full size experimental monozone house built at the U...This paper deals with the experimental investigation of hygrothermal behavior of wooden-frame building enve-lope.The experiment was based on in-situ monitoring of a full size experimental monozone house built at the University of Lorraine.Variations in temperature and relative humidity inside and outside the envelope were logged simultaneously with local meteorological data.Results showed the high coupling between temperature and relative humidity variations within the envelope materials.An overall hygrothermal response of the wall highlighted an interesting hygrothermal dynamic behavior of the envelope which may contribute to mitigate variations of relative humidity inside the building.Nevertheless,relative humidity evolves within a range of values that can lead to mold growth at a certain position which may alter wooden envelope life.展开更多
基金We thank to the China Scholarship Council(CSC)for its financial support to the first author,No.201808120084.
文摘Phase Change Materials(PCMs)have high thermal inertia,and hemp concrete(HC),a bio-based concrete,has strong hygroscopic behavior.In previous studies,PCM has been extensively combined with many materials,however,most of these studies focused on thermal properties while neglecting hygroscopic aspects.In this study,the two materials have been combined into a building envelope and the related hygrothermal properties have been studied.In particular,numerical studies have been performed to investigate the temperature and relative humidity behavior inside the HC,and the effect of adding PCM on the hygrothermal behavior of the HC.The results show that there is a high coupling between temperature and relative humidity inside the HC,since the relative humidity changes on the second and third days are different,with values of 8%and 4%,respectively.Also,the variation of relative humidity with temperature indicates the dominant influence of temperature on relative humidity variation.With the presence of PCM,the temperature variation inside the HC is damped due to the high thermal inertia of the PCM,which also leads to suppression of moisture evaporation and thus damping of relative humidity variation.On the second and third days,the temperature changes at the central position are reduced by 4.6%and 5.1%,compared to the quarter position.For the relative humidity change,the reductions are 5.3%and 5.4%on the second and third days,respectively.Therefore,PCM,with high thermal inertia,acts as a temperature damper and has the potential to increase the moisture buffering capacity inside the HC.This makes it possible for such a combined envelope to have both thermal and hygric inertia.
基金The French region Grand Est,the European Regional Development Fund and EMPP Scientific Pole of the University of Lorraine are acknowl-edged for their financial support.
文摘This paper deals with the experimental investigation of hygrothermal behavior of wooden-frame building enve-lope.The experiment was based on in-situ monitoring of a full size experimental monozone house built at the University of Lorraine.Variations in temperature and relative humidity inside and outside the envelope were logged simultaneously with local meteorological data.Results showed the high coupling between temperature and relative humidity variations within the envelope materials.An overall hygrothermal response of the wall highlighted an interesting hygrothermal dynamic behavior of the envelope which may contribute to mitigate variations of relative humidity inside the building.Nevertheless,relative humidity evolves within a range of values that can lead to mold growth at a certain position which may alter wooden envelope life.
