PR2010

Residential buildings newly constructed in Japan are well insulated and airtight for energy conservation. However, the indoor environment of these houses can suffer from high humidity in the summer and low humidity in the winter. In order to mitigate this problem, hygrothermal materials are installed in some Japanese houses. The test method for small samples of hygrothermal material is prescribed in the Japanese Industrial Standards (JIS). However, the moisture buffering effect of the hygrothermal materials adopted in actual houses is unclear.

In Korea, in 2006, the building regulation was revised to apply 0.7 ACH (Air Change Rate) ventilation systems to improve indoor air quality in residential apartment housing. The purpose of this study is to evaluate energy requirement and indoor contaminant level characteristics for residential building applying with sensor-based DCV (Demand Control Ventilation) system.

Although theoretical studies show that energy use for ventilation purposes can be reduced by more than 50% with DCV compared to CAV, evaluation of real energy use demonstrates that this potential is seldom met. DCV-based ventilation systems must become more reliable to close the gap between theoretical and real energy-performance.

When it comes to natural ventilation performance for large space cooling during summer time or intermediate seasons, double skin facade(DSF) integrated with cross ventilation(CV) exhibits more energy efficiency than single-side ventilated DSF. In this case, ventilation performance is remarkably affected by climatic conditions. Therefore, it is important to analyze micro climatic conditions before applying this passive technique.

The effects of roof window on ventilation flow rates and reduction of cooling loads in densely populated areas were investigated by using building simulations. In May of the intermediate season, when utilizing roof window, the cumulative number of air exchanges increased by 9 % to 12 % compared to that when the windows at side walls remained open only during the daytime. When the building coverage ratio increased from 0 % to 20 %, the cumulative number of air exchanges decreased and the cumulative cooling loads increased.

Cross-ventilation is regarded to be beneficial control method to obtain thermal comfort in a hot summer without using mechanical devices. Since it is complicated flow phenomenon, details of flow characteristics have not been sufficiently known. The final goal of this work is to establish a new prediction method of flow rate based on energy balance within the stream tube passing through or around the building. To validate numerical results obtained by CFD, they need to be compared with experimental results.

Korean government established a target to reduce greenhouse gas (“GHG”) emissions to 30% by 2020 to cope with the United Nations Framework Convention on Climate Change (UNFCCC) and secure its national competitiveness, and prepared a roadmap to develop this project. Especially, the government set up the objective of Zero Energy Consumption for the newly constructed multi-family housings by 2025 to reduce CO2 in the building sector.

Reduction of infiltration in the Equinox House, a residence under construction in Urbana Illinois, has been characterized through a series of blower tests as different joints and seams in the building were sealed. Equinox House is constructed with 30 cm thick SIPs (Structural Insulation Panels) wall and roof panels consisting of a Styrofoam core and oriented strand board sheathing on interior and exterior surfaces. Blower door tests were performed as each type of seam in the house was sealed.

The objective of this paper is to present a new method for estimating effective flow areas not only in the external wall of a house but also in the internal walls between rooms using only one type of tracer gas. The discharge coefficient of each wall and the pressure in each room—which are unknown variables—are determined using nonlinear simultaneous equations, which consist of balance equations for the air mass and tracer-gas concentration in the rooms. To verify the validity of this method, we performed a numerical experiment.

Museum showcases represent a peculiar confined space were ventilation and indoor climate conditions play an important role. Conservation of the works of arts, in fact, requires a control of the environmental parameters, with a tolerance usually far tighter than that required for assuring the comfort of people.