In estimating the energy consumption of residential air conditioners, which is affected by various operating factors on the user side, it is necessary to consider the environment distribution (i.e. temperature) in the air-conditioned room and start a discussion closer to reality. In this paper, by implementing a simulation program combining the CFD model and inverter air conditioner model, the temperature distribution in various operating conditions during heating period and the running situation of the corresponding air conditioners have been reviewed. It is concretely shown as the results that under usual supply condition, various temperature distribution may be generated in the room, thus complete mixed model is found to be inadequate in calculation.

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This report describes the results from the questionnaire and detailed survey conducted in 2002 and 2003. The 15 items of questionnaire included in facilities management, maintenance management, saving energy, art gallery facilities. The number of museums investigated by questionnaire survey counted for about 140 art galleries in Japan. From the survey results, we discuss the tendency and characteristics about each item. This paper has emphasized the importance of having the facilities・maintenance management in art galleries.

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This paper proposes a distributed cooperative cogeneration network system (CGNS) and analyzes the effects of CGNS on carbon dioxide reduction and load leveling for a distribution grid of a residential area in consideration of power limitations. In CGNS, cogenerations accommodate each other with the excessive electricity using the grid. Additionally, the system is equipped with heat storage system and is operated cooperatively to achieve load leveling for power system. The results show that this system can drastically increase the carbon dioxide reduction effect as compared with the conventional cogeneration system without networking. It was also confirmed that this system has the capability of load leveling. It is expected that CGNS can be a valuable energy system to realize cooperation between energy companies and to promote the introduction of cogeneration systems.

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The characteristics that metal hydride generates heat at absorption process and absorbs heat at desorption process is possible to make new air conditioning system without fluorocarbon. An innovative thermal storage system with metal hydride applied to air conditioning of buildings is investigated. This system is composed of two heat storage vessels of a "shell and tube type" heat exchanger with heat transfer fins and filled with metal hydride and a compressor equipped for hydrogen transfer. As the design conditions for this system, the heat load is assumed for two persons in 10m^2 with 3.49MJ/h. The performance of the metal hydride heat storage system is evaluated to use so-called peak shift operation. As the experimental result, the thermal storage system adequately works at the performances of heat storage over a 9-hour period at night, and cooling capacity over a 10.1-hour period during the day. Farther more, the coefficient of performance of this system is 2.8. It is nearly same as the coefficient of performance of ice thermal storage system.

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Recently, it has been confirmed that ozone in room air actively generates various free radicals by reacting with the organic and inorganic compounds existing in the air. The free radicals and other products of chemical reactions are often more irritating than their precursors. In particular, the products of ozone/terpenes reactions cause greater airway irritation in mice than would be predicted based on the known response of mice to ozone or terpenes. Such chemical reactions can significantly alter the concentrations of indoor pollutants. Furthermore, heterogeneous reactions between ozone and various surfaces occur, which further reduce the ozone concentration and must be considered in the ozone balance of indoor environments. Weschler and Shields (2000) have simulated chemical reactions in indoor air using mass balance models and assuming perfect mixing; these simulations examined the influence of ventilation rates on uni- and bimolecular reactions. Using computational fluid dynamic (CFD) simulations, Sorensen and Weschler (2002) have reported the distribution of chemical compounds resulting from various indoor chemical reactions. However, there is insufficient data to experimentally verify the two-dimensional or three-dimensional distributions resulting from chemical reactions in indoor air. Here, we isolate the surface reactions and measure the distribution of ozone within a 2D model room. The analyzed room model had one supply inlet and one exhaust outlet, with a cavity of dimensions 1.5m(x)×0.3m(y)×1.0m(z) in which a two-dimensional flow field was developed. A clear re-circulating flow was observed in the room generated by the forced ventilation. In order to discuss the order of chemical reactions or wall surface deposition for ozone, the concentration distributions of ozone in the model room were measured for various building materials. CFD analysis corresponding to the experimental conditions and with a built-in ozone wall surface deposition model was carried out. The results of CFD prediction were in good agreement with the room model experiment.

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