Two polyimide-matrix systems were subjected to a series of hygrothermal aging experiments at various temperatures and relative humidities. For each aging condition, we measured the microcracking fracture toughness as a function of aging time. The toughness decreased with time. The rate of decrease increased with temperature and relative humidity. All experimental results could be fit to a simpl...

Hygrothermal environments can degrade anisotropic conductive adhesive (ACA) joints by weakening the shear strength of adhesive interface. In this paper, the shear strength degradation model of ACA joints under hygrothermal conditions was formulated through experimental testing and theoretical modeling. The shear strength degradation data were obtained from different hygrothermal aging tests and...

A new hygrothermal building model is being developed within the research project GENSIM by the Fraunhofer institutes FIRST and IBP. The model implementation takes place by using the objectoriented modeling language Modelica. As a starting point for the development of the new building model, the researchers used the physical models of the simulation tools WUFI (hygrothermal wall simulation) and ...

Combined experimental and computational analysis of hygrothermal performance of an interior thermal insulation system applied on a brick wall is presented in the paper. In the experimental part, the functionality of the insulation system is tested at simulated difference climate conditions using a semi-scale device. The measured temperature and relative humidity profiles are used for the calibr...

In this article, the problem of time-dependent stress redistribution of a piezomagnetic rotating thick-walled cylinder under an axisymmetric hygro-thermo-magneto-electro-mechanical loading is analyzed analytically for the condition of plane strain. Using the constitutive equations, a differential equation is found in which there are creep strains. Primarily, eliminating creep strains, an analyt...

In most materials, there exists a coupling effect between heat and moisture during their transient diffusion. In particular, the coupling effect gives a significant change in the distributions of temperature and moisture concentration in some porous materials and resin composites (Chang, et al., 1991). Moreover, it is known that the absorption of moisture by hygroscopic materials under high-tem...

A long-term onsite assessment of the hygrothermal performance of a wood frame wall system is presented in this work. The system was applied in a wood demonstration house within the Lake Tai climate zone of Suzhou, China. The hygrothermal performance of the cavity insulation wall was determined from the temperature, relative humidity, and from the temperature of the wood material surface through...

Heating of green wood involves a complex set of deformation processes, including reversible thermal strain, reversible shrinkage due to decrease of moisture content, and irreversible viscoelatic recovery of growth stress activated by temperature called hygrothermal recovery (HTR). Experimental tests were performed on small Japanese Cypress specimens oriented in the three principal R, T, L direc...

This paper describes a current multi-disciplinary UK funded research project aimed at developing a hygrothermal model of house dust mite response to environmental conditions. The project involves the development of a transient hygrothermal bed model, which has been tested and validated by comparing its predictions with the environmental conditions measured in a bed in a test laboratory and in b...

Hemp concrete is more and more recommended by eco-builders because hemp is a renewable plant, recyclable and does not degrade within time. To integrate this material into buildings, it is important to study its hygrothermal behaviour. In this paper, two models have been investigated: a heat transfer model (Th) and a hygrothermal model accounting for heat and moisture transport through building ...