Firstly, thermal properties of PCM (paraffin, n-octadecane 94.4%) were investigated through various experiments, including DSC (Differential Scanning Calorimetry) tests. As a result, phase change temperature and latent heat of paraffin were measured, and the existence of supercooling and hysteresis in freezing process were also confirmed. Then, a nonlinear model for latent heat and model for hysteresis in phase changing process were developed based upon the experimental results. In order to validate the numerical model, another experiment was conducted by using the same PCM. Measured data were compared with the numerical results. Finally, numerical simulation for PCM wallboard containing paraffin was conducted by using the model for hysterisis, and the characteristics of PCM wallboard were investigated.

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The ventilation system in indoor ice skating arenas is usually planned for spectators. However, it was confirmed experimentally that players in arenas are much more sensitive to air contaminant than spectators in seats. In this paper, air quality in an ice arena was measured. The air in the arena was polluted by the exhausted gas from ice surface smoother vehicles and it was stagnant due to the cold air stratification in the lower part of the arena. The ventilation system of the arena was modeled and the distributions of air and pollutant concentration are simulated with Computational Fluid Dynamics (hereafter CFD). In CFD result, the cold stratification was reproduced and the concentration was found very high in the lower area. Several CFD case studies were conducted to develop effective ventilation system. CFD simulation shows that the pollutant concentration in the arena can be reduced when the supply outlets and the exhaust inlet for ventilation system are designed appropriately.

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In working spaces, such as factories and commercial kitchens, it is very important to remove contaminants generated during operations locally and keep air quality healthy in breathing zones. The push-pull ventilation system is considered as one of effective method in such condition, therefore it has been widely used in Japan recently. The effectiveness of the local ventilation system is affected by the airflow around it. If the airflow between push hood and pull hood is disturbed by the ambient flow, such as air jets caused by air-conditioning system for the occupied space, the contaminants could not be captured and the air quality in the breathing zone would become worse. Push-pull local ventilation systems consist of two components: the push flow is generated by push hood that are blown across the contaminate source towards an exhaust hood, which pulls and removes the air containing the contaminant. In this paper, a full-scale experiment in a laboratory on push-pull ventilation system was presented. The distributions of airflow and pollutant concentration were discussed with the experimental results. Several factors were investigated, i.e. the velocity of push-air and pull-air, and the locations of contaminant sources. Then a large-scale factory was modeled and simulated by CFD simulation, and the interaction between the local ventilation and the general ventilation was studied. If the displacement ventilation system was used as the general ventilation, the airflow formed in the push-pull ventilation system was not be disturbed and the capture efficiency of it was excellent.

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The operational planning of the energy network of the small fuel cell which connected each system of hydrogen, oxygen, waste heat, and electric power with piping or the electric wire is considered. Arbitrary fuel cells can be power-generation-operated or water-electrolysis-operated at arbitrary sampling time. When the fuel cell which carries out power generation operation is in the situation of partial load, water electrolysis operation is performed by other fuel cells. Consequently, the driving point of the fuel cell to generate operating is shifted to a high efficient area, and it is predicted that the whole system efficiency goes up. The hydrogen and oxygen which were generated by water electrolysis operation of fuel cells are stored in each cyinder through the network. And the hydrogen and oxygen of each cylinder shift time and are consumed by power generation operation of fuel cells. The method of the operational planning analysis was considered installing such a fuel cell network system into five residential houses of the Sapporo city. From the results of analysis, the effect of the water electrolysis operation system of fuel cells is concentrated on summer of low thermoelectric ratio. Therefore, when introducing this system into the area where a thermoelectric ratio is smaller than Sapporo city, the effect of energy saving is more large. From the developed analysis method, the maximum of the hydrogen quantity to be stored is 1.25kg, and the maximum quantity of thermal storage is estimated to be 55MJ.

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Latent heat thermal energy storage tanks have been developed. The feature of the tank is to utilize heat transfer enhancement with high-thermal conductive carbon fibers. The tanks are set in an air-conditioning system in a building. The thermal charge and discharge characteristics of the tanks are investigated. As a result, the thermal energy releases from the tanks for 8 hours with the energy released rate nearly 40kW. The released ratio can be improved when the appropriate amount of the thermal energy storage material are packed in the tanks, resulting in achieving the design objective of the tanks. It is preferable that the heat transfer fluid flows from the bottom to the top in the tanks for effectively using the natural convection heat transfer.

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This study demonstrates the possibility of free cooling system with open type cooling tower. Free cooling system is an energy saving system without chiller operation when the ambient temperature is relatively low and building needs the chilled water for cooling. The prediction method for free cooling performance with commercially available cooling tower are described in this paper with the theoretical formulae which have been proposed to predict the performance of cooling tower. The water temperature and the quantity of flow were measured in summer and winter in order to derive the parameters and the characteristics of open type cooling tower. The predicted inlet and outlet water temperatures were agreed well with the measurement, and it also shows the free cooling system with cooling tower may be available in Japan.

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This study discusses the drainage performance evaluation and the design method of horizontal drainage pipe systems with drainage header piping, which are applied to SI housing units. The drainage performance evaluation was also discussed in the previous papers by focusing mainly on drainage systems comprising horizontal drainage pipes between the drainage stack and the sanitary fixture with lengths exceeding 7m ('total piping length' hereafter). For domestic waste drainage systems, the piping length between the drainage header, a confluent point of drainage flows, and the sanitary fixture ('drainage header piping length' hereafter) exceeded 5m. In reality, however, there are many drainage systems that are configured with total piping lengths and drainage header piping lengths that are shorter than those used for our studies. It is suspected that shorter piping lengths relate to the performance of the combined drainage inducing siphon and the rate of backflow, which have a significant influence on the overall drainage performance. Based on the assumption that a horizontal drainage pipe system employs the total piping length and the drainage header piping length that are both short, this paper conducts a combined drainage experiment and discusses the evaluation methods of the system's drainage performance. Merits of having such a drainage system in SI housing units are also examined based on the results of the experiment.

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When a fire accident occurs in the upstream tunnel of successive tunnels connected by a Snow-Shed, it is necessary to control the ventilation so that damage does not expand by smoke flowing downstream. We analyze this phenomenon by means of a three-dimensional simulator using Large Eddy Simulation to examine the interference between successive tunnels, and defined the interference rate I as the ratio of smoke densities in successive tunnels. From comparisons between simulation results and experimental results we confirmed that the simulations have reasonable accuracy. In this way, the rate of interference of fire smoke between the two tunnels was almost in agreement. Many simulation results carried out under various conditions confirmed that the interference rate is governed by the Froude Number, the ratio of longitudinal ventilation velocities of the two tunnels, the dimensionless distance between the tunnels, and the inclination of the Snow-Shed. Each parameter was examined for its influence on the interference rate. Finally we derived the evaluation formula of the interference rate.

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It is not rare that owner's demand on the indoor environment and energy consumption are not satisfied enough due to faults at the plan/design phase or the Planning/designing change at the construction/operation phase. Therefore, commissioning at each phase of plan, design, construction, acceptance and real operation should be carried out in order to satisfy the function and performance of building/HVAC system as intended by the owner's requirements. Simulating the comfort and performance of building/HVAC system is one way to carry out commissioning accurately and effectively. The present paper used a new building energy simulation program; EnergyPlus that was released in April 2001, as a tool for a study on the applicability of HVAC simulation program at each commissioning phase and it shows how the program could be handled and applied using a modified actual building as an example.

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A receiving tank and an elevated tank are providing a problem to cause deteriorated water quality. This paper evaluates the structure of the water tanks by using the Morril index and the short-circuit index. The kinds of apparatus used a square water tank and an oblong style water tank. In addition, two water tank apparatus are installed with partition and provided with detour flow. There are holes of diameter 26mm (one or more) and 6mm (two or more) on the partition This makes the water tanks possible to promote the flow to be more pushed out.

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This paper describes a study on the performance evaluation of a hybrid ventilation system with a heat exchanger. This system has two passive stacks and a heat exchange unit, which includes a heat exchange element, a supply fan, an exhaust fan and a bypass route with a damper. In order to evaluate the system performance, the experiments using a full-scale test house and the numerical simulations have been performed in winter and mid seasons. The ventilation rate and the heat recovery rate under the various conditions of the fan and the damper operation were measured. The results of the experiments are as follows. 1) The leakage in heat exchanger is very small, but the leakage rate when only exhaust fan is used is larger than another condition. 2) In case of the passive ventilation, the ventilation airflow rate is insufficient, and the reversal flow in the supply duct occurs. 3) When the supply fan is not operated in winter, the ventilation airflow rate to the 2nd floor rooms is insufficient. 4) When either the supply fan or the exhaust fan is operated, the ventilation airflow rate is more than 0.5 times per hour.

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This thesis deals with ways to estimate direct and diffuse illuminance from horizontal global irradiance based on data on irradiance and daylight illuminance gathered every minute for ten years in Chofu, Tokyo. Direct illuminance was estimated by three methods. The first method used the luminous efficacy of daylight of direct illuminance to measured global irradiance defined in this thesis and that of diffuse illuminance. The second was based on the division method of direct and diffuse daylight illuminance from measured global horizontal illuminance jointly with the conventional luminous efficacy of daylight. The third utilized the past division method of direct and diffuse solar irradiance from measured global horizontal solar irradiance and the conventional luminous efficacy of daylight. The comparison of the three methods has quantitatively shown the method proposed in this thesis, in which illuminance by component was estimated directly from global irradiance, to be plain and practically accurate.

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This study described an examination of methods for measuring performance of silencers. Pressure loss was measured by a method using the substitution duct based on ISO7235, and by the direct method. Insertion loss was measured by a method using the substitution duct based on ISO7235, and by the substitution method without the substitution duct. Results indicated that pressure loss for lined elbows as measured by the substitution method using the substitution duct based on ISO7235 and by the direct method were not equal. Insertion loss values for lined elbows obtained by the substitution method using the substitution duct based on ISO7235 and by the substitution method without the substitution duct were equivalent.

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From 1960 to 1990, reading of meteorographic paper and other manual work were required to draw up hourly weather data in Tokyo. Since 1991, SDP (Surface Daily Data Observation Point) data gathered by the Meteorological Agency have made it easy to obtain those weather data every hour. Based on the 40-year-long weather data, outdoor design conditions for cooling and heating in every decade between 1960 and 1999 were set. Regarding fluctuations in temperature under those conditions, the daytime highest temperature has not changed much during that period, while the lowest temperature has risen decade by decade. The intensity of solar radiation has increased slightly. Due to small changes in absolute humidity despite increases in temperature, relative humidity has fallen, causing air to become dry. The outcome of the calculation of cooling and heating load during that period shows that annual cooling load has been on the rise year by year, but that the margin of decrease in heating load has been widening.

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