Air-conditioning systems with breeze-line type outlets are frequently adopted for perimeter zones in office buildings. However, it is pointed out that several examinations are required for the establishment of design criteria on position, shape and direction of the outlet. The purpose of this study is to establish design criteria on breeze-line type air outlets adopted for air-conditioning systems for the perimeter zone in office buildings. The previous reports described experimental facilities and the results of examinations on the length and the number of a new air-conditioning system with breeze-line type air outlets. In this report, the experiments on outlet direction of the breeze line for the summer season air-conditioning, and on the indoor thermal environment were performed.

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The collective humidification method incorporating an outside air controller is mostly used to humidify outside air introduced into clean rooms for manufacturing electronic devices such as semiconductors and flat panel displays (FPDs). The method consumes a lot of heat energy in the form of steam and other forms. To reduce such heat loads, various heat recovery systems have been in practical use. However, the higher the effect, the larger the systems, which is why they are suitable for factories to be newly constructed but cannot be added to existing ones. This report suggests adding a water spray humidifier to the indoor system of an existing clean room as energy-saving equipment during wintertime, and estimates its energy-saving effect. By examining the amount of energy saved and CO_2 emissions reduced in a typical model, the effectiveness of water spray humidification for indoor systems was clarified.

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A mixing model with simple one-dimensional diffusion, for a temperature distribution in a heat storage tank of the multifunctional heat pump hot water supply system, which middle warm water (30〜60℃) returns to the tank central part is presented. The feature of the model is assuming the thermal diffusion under buoyancy effect in the tank to be change of thermal resistance. Temperature distribution in tank calculated with the mixing model is compared with experimental results in an actual multifunctional heat pump hot water supply system with a floor heater. And the accuracy of the model is validated. Applying the model, the best point for low energy consumption of floor heater circuit return position is studied.

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A steam heating system using heat pump is designed and experimentally evaluated. The water (steam) used as a secondary coolant has a small global warming impact and evaporation and condensation of water easily convey the coolant without pump power. The heating system has a smaller global warming influence when a natural refrigerant is adopted for the heat pump. Performance of the system is evaluated by changing concentration of air in the steam heating system, height of water head, temperature of heat source and load temperature. The system could be operated continuously, and there was an optimal height of water head. COP increased with increasing temperature of heat source and decreasing load temperature as shown in conventional heat pump systems. On the other hand, COP decreased with increasing air concentration in the steam pipe.

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