The performance of ground source heat pump (GSHP) system significantly depends on configurations of ground heat exchangers and thermal properties of underground. For the optimum design of a GSHP system, it is necessary to comprehensively consider the conditions of ground and groundwater, and to accurately predict the heat extraction and injection rates of the heat exchanger. The numerical model to predict heat exchange rate of ground heat exchanger is described in Part 1. In this paper, a design tool for GSHP system using the numerical model is described. To set suitable arrangements of ground heat exchangers and flow rate of circulatory water, the application to real site in Tokyo has been conducted. The thermal and hydraulic properties (thermal conductivity, thermal capacity, permeability, etc.) have been estimated by samples of boring test and ground heat exchanger model installed around a building pile has been used in calculations. In the results, the heat exchange rate, COP (coefficient of performance), and underground temperature on the several cases have been predicted by the developed tool. In the result of base case, which used 8 pairs of U-tubes with a 3.041/min of flow rate, the heat exchange rate was 181.6W/m in cooling, and 160.4W/m in heating and the ground temperature at an observation point presented about 1℃ of annual fluctuation.

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Personal air-conditioning system which uses multi-flow ceiling cassette type packaged air-conditioner was examined by CFD in this study. Multi-flow ceiling cassette type packaged air-conditioner was used both for ambient zone and personal zone. In personal zone, human demanded the cooler air than ambient zone. By the result, useful design material which indicates the supply air condition that leads to energy saving and the demanded PMV level by the human in the personal zone, was obtained.

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The objectives of this study are to develop the weighted heat flux evaluation method for various countermeasures against urban heat island taking into account differences in the thermal diffusion caused by generation time of heat flux and horizontal and vertical discharge positions of heat flux. Using two types of numerical simulation model, one is a three-dimensional meso-scale meteorological simulation model to evaluate the temperature influence caused by the change of heat flux discharge or generation and another is an one-dimensional meteorological simulation model to estimate the heat flux generated under a variety of building conditions. Then, this study shows two case studies (one is for an apartment house and another is for an office building) that apply the developed evaluation method for various strategies against urban heat island. As a result, the effect of heat flux reduction that was released from relatively high position and in the daytime (for example, high reflective roof) evaluates relatively low score. On the other hand, the effect of heat flux reduction that was released near the ground surface and in the nighttime (for example, anthropogenic heat release from the house) evaluates relatively high score. So it was shown that the weighted heat flux evaluation method evaluates a characteristic between the space-time of the heat flux adequately.

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This paper deals with the performance evaluation method of a split air conditioning system. Generally, it is very difficult to evaluate the actual performance of a split air conditioning system, because the heat flux in an air blow unit is very complicated. Therefore measurement of the temperature and wind velocity is very difficult. Then, we propose the performance evaluation method based on characteristic curve of the compressor. We made regression equations of refrigerant mass flow rate that took evaporating and condensing temperatures as variables experimentally. These regression equations were obtained using the least square method. Cooling and heating capacity were given by multiplying the approximated mass flow rate by the differential of enthalpies pass through the indoor unit. The relative errors of the approximated mass flow rate from the measured values were within 5%. We compared the calculated mass flow rate with the previous detail data in order to verify these equations. Then the relative errors of the calculated from the measured values were within 5%.

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Recently, researches aiming at solving the influence which the artificial waste heat, especially, waste heat from air conditioning devices has on urban environment and urban canyon are made strenuously. In this research, examination has performed about the influence air conditioning waste heat has on the surroundings of a building. In Part 1, temperature distribution around the dry and wet cooled outdoor unit were measured. As a result, it was shown that temperature around dry cooled out door unit became temperature high on the whole rather than temperature around wet cooled out door unit. In Part 2, the influence the waste heat of multiple outdoor units for air-conditioning installed on the building affects external space was clarified. And, the influence the inlet temperature and load factor of the outdoor units affect the energy efficiency of air conditioning units was considered. In this report, comparison with the measurement result of the thermal environment around the outdoor unit and CFD analysis result was performed, and the reappearance accuracy of CFD analysis was verified. Furthermore, the case study according to installation situation of outdoor units was performed using CFD analysis. And the thermal environment around the outdoor units and the energy efficiency of the air-conditioning units were examined.

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In this thesis, we evaluated inside corrosion environments of a steel radiator in a hot water heating system as the following steps. [1] Circulating tap water or antifreeze as heat medium of the system for a week or a month [2] Measuring the concentration of the dissolved oxygen and analyzing the water quality of the heat medium We recommend the direct vent type using tap water as the heat medium for the following reasons. [1] When we selected the half direct vent type, the water contained a great deal of iron the radiator was made of after the circulation. [2] The reaction of the corrosion is possible to continue due to the residual-dissolved oxygen even if the total corrosion rate is decreased. We can select both the direct vent type and the half direct vent type using antifreeze as the heat medium for the following reasons. [1] Not only the iron the radiator was made of but also the cupper the system was made of was hardly solved into the heat medium even if we used either type. [2] The dissolved oxygen was consumed even if we used either type.

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Unit energy prices for Japanese households from 1960 to 2007 were estimated on the basis of the annual reports on the retail price survey. As for unit prices of electricity, the electricity consumption of average workers' household was counted in the estimation. Unit prices of city-gas in this note were estimated on the basis of population-weighted average of forty-nine cities. The estimated unit prices presented in this note were compared with the existing ones estimated by the institute of energy economics, Japan.

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It is common motivation to grasp the heat transfer efficiency on a rough surface in many research areas. To determine heat transfer coefficients based on the analogy of mass and heat transfer, mass transfer coefficients are frequently measured. The naphthalene sublimation method, the water evaporation method and the salinity method are available to measure mass transfer coefficients. This paper documents wind-tunnel experiments of mass transfer coefficients with the salinity method, which is rarely used for a rough surface.

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