This paper constitutes Part3 in the series of studies that aim at development of a design and performance prediction tool for the ground source heat pump (GSHP) system. The authors introduce calculation algorithm of the temperatures of the ground and heat carrier fluid in multiple ground heat exchangers for pipe arrangement of the GSHP system. Next, performance of GSHP systems with steel foundation piles is predicted with the design tool. In moderate climate region, since the GSHP systems using multiple ground heat exchangers with short length can operate with high efficiency as well as the GSHP system using a single ground heat exchanger with long length, the GSHP system with steel foundation piles has possibility to become popular. In addition, the authors investigated temperatures of the ground, thermal medium, and system performance according to the interval of the ground heat exchangers when annual heat extraction from the ground is equal to annual heat injection. The calculation results show that the applicable interval is 2m for the small-scale building. In a case where the large-scale building adopts the GSHP system with multiple ground heat exchangers, the adequate intervals for linear and lattice arrangement are 2m and 3m, respectively.

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In this thesis, the hydrogen absorption and desorption behavior of the Hydrogen Storage System with hydrogen absorbing alloys and the air heat exchange type container for residential energy system and stand-alone power supply was cleared. When the pressure difference between the alloy equilibrium dissociation pressure and piping was 0.1MPa or more, the hydrogen desorption characteristic of this system was excellent. When the absorption rate was 0.8MPa, the hydrogen storage capacity was dependant on the room temperature and the absorption rate. And it was showed that this system could have the extensive hydrogen storage capacity in the condition of the room temperature 5, 20℃ and the absorption flow rate 0.1NL/(min・kg), or the room temperature 35℃ and the absorption flow rate 0.025, 0.05NL/(min・kg).

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The overarching goal of this work is to develop the numerical method that reproduces the transportation of negatibe charged ions in indoor air. The numerical models are based on fundamental physicochemical and electrical principles of their convection, diffusion, deposition, recombination and self-attenuation (damping) in room air. To be more precise, electrophoretic migration model, wall surface deposition model based on molecular diffusion and electrophoretic migration, and uni-molecular and bi-molecular reaction model of negative and positive cluster ions were proposed. Towards this end, in this paper (Part 1), the coupled analysis of CFD (Computational Fluid Dynamics) and proposed numerical transportation models of cluster ions were carried out to aim at 2-dimensional model room. In this analysis, the effect of wall surface deposition based on molecular diffusion was relatively small compared with the effect of deposition based on electrophoretic migration. The concentration revel and recombination of negative and positive cluster ions were critical parameter of concentration distribution in indoors.

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Placement of sensors for controlling an HVAC system in a large indoor space is usually restricted; therefore, it is difficult to obtain reliable temperature and velocity distributions of the air in an occupied zone. In this paper, a method of overcoming this restriction is presented based on a gain-scheduled control system consisting a fuzzy model. Temperature distributions within the space as a function of various parameters, such as outlet air temperature, outlet air volume, and human body load, are predicted with CFD (Computational Fluid Dynamics) simulations, from which approximate fuzzy models are made. This model uses simplified fuzzy reasoning, and offers highly-accurate modeling of non-linear temperature characteristics. Fuzzy rules are generated automatically from data obtained using computer-generated CFD simulations. This gain-schedule control controls PID so that the representative temperature in the occupied zone is estimated from the value detected observed the temperature sensor using a fuzzy model, and the representative temperature in the occupied zone may reach a set value. HVAC control simulation using CFD shows that this gain scheduled control based on the fuzzy model achieves control with less offset than the conventional PID control using the temperature measured by sensor as the representative temperature in the occupied zone.

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We need the accurate estimation of energy consumption and the correct decision of performance and capacity for designing and planning of building systems. Therefore, it is important to survey and study on the actual condition of hot water consumption which is largely affected with energy consumption in each building. In Japan, many hot spa facilities, which are public bathhouses, are built because of the people's concern for health in these days. However, the data of hot water consumption which applies to designing and planning are insufficient. On the existing designing and planning, the volume of hot water consumption is estimated roughly and the hot water supply systems are not designed optimally. The purpose of this study is to clarify the characteristics of hot water consumption of a hot spa facility located in Hiroshima City. The objective hot spa facility has two bathrooms for male and female, a restaurant, and a massage room, etc. As for the hot water supply system, the hot water is heated by four electric water heaters, four CO_2 heat pump water heaters, and two hot water boilers. As for the measurements of hot water consumption and temperature, the measurements were carried out at four seasons over a year and all data were recorded in every one-minute. We obtained the data for the number of customers from the manager in this building. On the basis of these data, at first, the number of customers in the restaurant and the bathrooms were analyzed and the customer's tendencies of fluctuation grouped into weekday, Saturday, and holiday were clarified. Next, the cold and hot water temperature, consumption and heat loads were analyzed in each usage of the hot spa facility.

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The energy saving analysis of the photovoltaic array and the solar collectors for domestic hot water installed on the roof of a detached house built in built-up area were simulated by TRNSYS and its module, MASK (Type68), which reflected the sun-shade of circumferential buildings. The results are as follows: The installation of the solar collectors for domestic hot water in consideration of quantity of hot water supply of daily use may be prior in order to get the maximum energy saving. Japanese government must pursue the popularization of the solar collectors in order to valid the CO_2 exhaust reduction by solar energy use, which has been reported by Kyoto protocol.

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