English

A purpose of this research work is to study the environmental control in large indoor stadiums which utilize the natural ventilation. In these problems, effects by the airflow in and around the stadium should be analyzed. In this research work, a numerical analysis technique which enables simultaneous simulation of indoor airflow and the airflow around buildings was developed adopting composite grid coordinate calculation technique. In this paper, an outline of this technique is described.

This study was conducted to determine how sash movements affect the performance of fume hoods. The performance of two fume hoods was studied as the sashes were moved from closed to open position at speeds of 2 ft/s, 1.5 ft/s, and 1 ft/s. The tests were conducted with fume hoods operated at both constant volume and variable air volume. The tests indicate that sash movements can disturb airflow patterns at the face of the hood and potentially affect the performance of the hood. The effect of the sash movement varied with hood type and speed of sash movement.

Applicability of CFD simulation to designing passive architectures was investigated using a passive solar room with a Trombe wall system inside it. In the investigation non-steady numerical simulation was performed to predict thermal environment in the test room. Two weather models assuming a typical fine winter day were compared, one was the model based upon the data in Osaka and the other was that in Sapporo. The test room has glazing in the south side wall and in the north side one. Each glazing was covered with an insulating door during night.

The concept of dynamic insulation, where cold air is drawn through porous insulation in a building envelope from outside to inside, thereby returning heat energy normally lost by conduction back into the interior of the building, has been studied by several researchers, in Japan, Europe and Canada. However the work to date has largely concentrated on the physical processes in individual wall, floor or roof elements and only a small number of experimental buildings (all of a small domestic scale) have been adequately monitored.

A passive solar house with sunspace made of reinforced concrete was constructed in Sendai, Japan in 1984. One year measurement of room temperatures were recorded. Also, detail measurements have been made during the summer and winter seasons. Further, calculation of indoor temperature was conducted using response factor methods for studying the thermal effects of the sunspace on the indoor environment. This paper describes the measurement and calculation results.

Entertainment clubs, nightclubs, theaters, restaurants, and coliseums, with their highly variable occupancy rate, are excellent candidates for demand-controlled ventilation. The dynamic thermal requirements of both heating and cooling, coupled with the need to control indoor air quality because of the large number of patrons who also may be smoking during the highest occupancy, provide an opportunity to integrate the temperature controls with an indoor air quality control system.

As the sensible heat gain or cooling load are decreased by using thick thermal insulation in a building, the need for dehumidification increases. Especially in Kushiro, it is rather cool and humid in summer because of its foggy weather. In this study, two types of dehumidification systems were developed and their performances were examined. The first is a heat-recovery type, which uses a cooling coil and a sensible heat exchanger. The second is a moisture-absorbent type, which uses heating and cooling coils and an absorbent.

Although most new houses in the Hokuriku region are equipped with air conditioners, some people living in farmhouses still feel that cross ventilation is more desirable. Comparative measurements were made between a new house and a farmhouse. Simplified simulations were also carried out to clarify the effects of thermal insulation and earth floors on cross ventilation in summer. The role of thermal insulation in hot and humid regions is different from that in cold regions, where there is a large difference between outside and inside air temperatures.

Thick insulation in buildings offers great potential not only for decreasing cooling load but also for changing its calculation method, and for changing system design, operation or control of the system and the thermal environment of the room. The research results of room air temperature changes in well-insulated buildings, show the effects of the daily swing of outdoor temperature and solar radiation are quite small. A simple calculation method for cooling load based on steady state theories is available for such buildings.