Today, it is globally known that climate change needs to be addressed to mitigate its harmful effects on our environment. It is also common knowledge that the contribution of historical buildings to the energy consumption of the existing Canadian building stock is severe. Buildings of historical identity are often poorly thermally insulated. Thus, to increase energy efficiency and occupant comfort in cold climates, the application of thermal insulation on the interior side of solid masonry walls offers a possibility to improve the historic buildings' energy performance, without compromising their identity and cultural heritage values. As a result, the historical masonry will be subjected to lower temperature during the heating season, which can increase the potential for condensation and frost within the wall. A balance must therefore be reached between durability measures and thermal performance objectives. This paper intends to achieve this balance through determining the impact of the interior insulation thickness on the durability of a typical historical masonry wall under the effect of climate change. A stochastic approach is used in hygrothermal simulations to account for the uncertainty in material properties. Results in Ottawa indicate a higher risk to frost damage after interior insulation is added to a brick wall having a moisture critical degree of saturation (Scrit) of 0.25 and 0.35. Moreover, both deterministic and the stochastic results were in good agreement. Also, both methods showed an increase risk to frost damage under a changing climate.

Hygrothermal simulations are necessary to permit analyzing moisture performance when designing building envelopes. Owing to the high computing time and cost of the long term simulations, a common approach is to select representative year(s), the Moisture Reference Year(s), from a longterm series of climate data. It is assumed that the use of Moisture Reference Year(s) (MRYs) provides equivalent results as those provided using long-term series. The selection of MRY(s) is by itself based on the one of the methods available in the literature. In the present study, three methods of selecting the MRYs were evaluated i.e. the moisture index (MI), severity index (Isev) and climatic index (CI). Simulations were performed using individual years of historical climate data extending from 1986 to 2016 and projected future climate data representing the scenario with a 3.5°C increase in average temperature which is expected to occur from 2062 to 2092. Brick cladding installed on a wood frame wall assembly subjected to the climate of three different Canadian cities was selected for analysis. The cities selected were Vancouver (BC), Calgary (AB) and Ottawa (ON). These cities have differing levels of moisture loads. The year having the mould index value more than 3 for highest number of hours among the individual years was compared with the MRY given by three selected methods. A method was considered to be accurate in terms of the prediction if the year selected by that method gives the number of hours with mould index more than 3 which lies in the same class as that of year having maximum corresponding value. In general, it was observed that none of the methods provides the worst year with 100% accuracy, however for most of the cases, Isev method performs better than other two methods in terms of MRY selection.

During the transmission of ultrasound, its great directionality, ubiquitous penetration and the ability to strengthen the diffusion, exchange and transfer of matter can help the treating fluid reach the crossing points of silk fabric. And the function of ultrasonic wave can make use of acoustic cavitation effect to produce impact on sericin layer at the crossing point, thus promoting the fragmentation and separation of sericin, improving the removal efficiency of sericin at crossing points and achieving uniform silk fiber degumming. The function of ultrasonic wave can cut down the time of process and avoid the damage of fibroin through controlling the temperature and dose of chemical agent.

This study presents an experimental investigation of the relationship between liquid surface tension and fabrics water retention in dehydration processes such as centrifuging, line drying and heat drying. Selected surfactants were used to prepare wash baths with different surface tension, and dehydrating experiments of cotton fabric after immersion in above bath were conducted. The results showed that lower surface tension is beneficial to reducing fabrics water retention by centrifuging and improving line drying efficiency and heat drying efficiency. It was assumed that water with low surface tension is easy to drop down or separate from fabric, thus improving the de-watering and drying efficiency.

Vapor diffusion ports (VDP) that are drilled in the exterior sheathing of wood-frame walls are commonly used in wood-frame construction in the coastal region of British Columbia with the intention to improve the drying capacity of wood-frame exterior walls. This practice was originated following the systematic building envelope failures due to rain penetration that occurred in this region around 1985-1995. A previous laboratory study carried out by FPInnovations found that the diffusion ports provided substantial improvement in the drying rates of Oriented Strand Board (OSB) sheathed walls, but not for plywood sheathed walls (Hazleden and Morris, 2001). A more recent laboratory test (Wang, 2018) using wood-frame walls with higher insulation levels in compliance with the current more stringent energy code found that VDPs did not significantly improve the drying rates; On the other hand, the provision of VDPs may allow moisture ingress into the wall assembly instead in a damp environment. The difference in these two studies in terms of test wall sizes, moisture sources, and test conditions may have attributed to the different findings. To provide a more comprehensive and systematic evaluation of the effect of VDPs, hygrothermal simulations using Wufi-2D are carried out in this study. The Wufi-2D model is firstly validated by comparing simulation results to the test results provided by Wang (2018), which tested the effect of VDPs under laboratory conditions by using a wetted wood block installed inside each wall assembly as a simulated moisture source. The simulation results agree well with the measurements. The Model is then used for sensitivity analysis with different levels of rain leakage with and without VDPs using yearly weather data. The variables included are types of exterior insulation, types of sheathing (OSB versus Plywood), and types of sheathing membrane. This paper presents the validation of the model and simulation results under transient conditions with rain leakage. General conclusions on the effect of VDPs are provided.