small office buildings have the following characteristics: the floor area is often small and most of the floor is occupied by perimeter zones; the exterior walls and windows are often poorly insulated; packaged and multi-unit air-conditioning systems have a dominant share in the air-conditioning systems. The authors measured the heat load of the air-conditioning system and the air temperature distribution of an office room with the abovementioned characteristics of small office buildings. The result revealed that a large vertical temperature distribution is formed in the room during the winter. The air-conditioning system of the room could not supply the required heat to the room because the system was controlled using the inlet air temperature of indoor units of the system; the inlet air temperature did not represent the air temperature of the room owing to the vertical temperature distribution. This decreases the comfort in the room. To solve the problem, the authors used fans to circulate air in the room to disturb the temperature distribution. As a result, the supplied heat to the room significantly increased. The authors also carried out a heat load simulation to quantitatively estimate the extent to which the heating load can be reduced. The result showed that the heat load could be significantly reduced by improving the insulation performance of the outside walls and windows as well as by reducing the area of the windows.

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A new axial flow cyclone dust collector was developed as the intake hood for functioning as an air cleaner in a house ventilation system. Filter maintenance poses a problem in ordinary air cleaners; however, the cyclone dust collector has no such problem. However, conventional cyclone dust collectors are not suitable as the intake hood because of their large size, long conical shape, and high pressure loss. The new developed axial flow cyclone dust collector, which is compact and has a high capture rate and low pressure loss, will be useful in solving these problems. The purpose of this study is to determine the optimum design parameters of the axial flow cyclone dust collector and verify its advantages as an intake hood in house ventilation systems. We elucidated the relationship between the design parameters of the cyclone dust collector and its performance as an intake hood for functioning as an air cleaner. The optimum design parameters, for increasing the capture rate and decreasing the pressure loss, were also shown. This cyclone intake hood works well, reducing the filter maintenance cost.

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To decrease the indoor VOC concentration in a vehicle the Japan Automobile Manufacturers Association, Inc. is tackling the self-imposed control of indoor VOC concentration in a vehicle. Although high-boiling-point substances, such as phthalate ester, are part of the substances for self-imposed control, these high-boiling-point substances are difficult to quantity with sufficient accuracy in the collection using the conventional tube (Tenax-TA). Thus, we examined an evaluation technique that uses a glass plate as the STET medium of a high-boiling-point substances for quantitatively evaluating high-boiling-point substances. This paper reports on the result of the method for selecting the plate for the quantitative evaluation technique of a high-boiling-point ingredient, and storage. As a result, the adsorption of DEHP was excellent with a quartz plate. The storage was able to maintain reduction the DEHP after a collection with 6% error by storing using a plate of the same material.

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In this study, to develop a method for determining the properties of a local opening based on the result of a fan pressurization test on local openings, an equation for the combination/separation of the opening properties of natural air supply systems is presented and an experimental investigation is performed. In this paper, firstly, we first introduced an equation for the combination/separation of the opening properties of series placement, and the results of the experimental investigation of the equation in a test house are shown. Then, a model experiment on the opening properties of natural air supply systems is performed after which a numeral analysis is conducted on the effect of connecting ventilation equipment on the opening properties. It is found that the accuracy of the equation for the combination of opening properties is high (less than 5% error) but the accuracy of the equation for separation of opening properties is limited. And effect of connecting the equipment is modified using the presented method (Error is less than ±10%)

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