The present study has dealt with microbubbles generation from high pressure water with high air solubility by depressuringation. The experiments of generating air micro-bubbles were preformed for water pressure, water temperatures, an depressuring nozzle diameter etc. as a parameter. Inthe case of air microbubble generation from air super-saturated water by decompression, air bubble growth from its nucleus was influenced by water viscosity, and the generated air bubble diameter was decreased with an increase in the ratio of air concentration in a pressurized water to its concentration at an atmospheric pressure and Schmidt number. Finally, nondimention equations of air microbubbles were derived from nondimensional parameters.

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This study suggests a simplified measuring system for ventilation effectiveness using a CO_2 stats on ceilings to improve installation and data-processing. The comparison between the above and the conventional measurement system using the sampling tube has been conducted in an experimental house with the Centralized HVAC system, that has return air over 2 times an hour, and the mechanical supply and exhaust ventilation systems. In the measurement at the same breathing height (F.L.+1.1m) using the stats and the tubes, the results of both measurements mostly agree at the Step-Down method, but there's about 10% difference at the Step-Up method. There's a little difference (about 10%) between the stat method on ceiling (F.L.+2.4m) and the tube method at the height of breathing, regarding the result of measurered outdoor air distribution. So. it is certified that the proposed method to measure ventilation system effectiveness with large return air volume is serviceable.

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This paper describes performance evaluation of a polymer electrolyte fuel cell for applying to the demonstration on hybrid utilization of renewable energy and the fuel cell for a residential energy system. First, experiments of characteristics on heat and power generation were carried out. Direct current electrical efficiency and the heat recovery efficiency at a rated output operation were quite high; 42.5% and 49.2%, respectively. Second, characteristics of partial load, water temperature for heat recovery, start-up time, load following and exhaust gas were clarified. Finally, the measurement on characteristics of a hot water tank was carried out, and it was proved that the sufficient performance can be obtained even under continuous operations.

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This study is aimed at the performance evaluation and design method of the horizontal fixture drain branch pipe system with drainage header piping, applied particularly to dwelling units of SI housing. The first report clarified the performance evaluation method for the above mentioned system by setting up a piping model as well as specifying the drainage characteristic of the system. Th〓〓 report focuses on the design method and load estimate calculation technique in order to discuss the following issues. First, the average flow rate of a typical sanitary fixture (qd-value) is acquired using the steady flow rate method stipulated by HASS206. The qd-value is required for the estimate calculation of load on the drainage stack and its declining characteristics in parallel with the increase of pipe length is acquired by quantitative calculation. Next, the data obtained as above is reflected in the load estimate calculation in order to examine the load influence on the drainage stack for Super high-rise apartment and the feasibility of adaptive heights.

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The largest proportion of energy in housing is consumed by hot-water supply system, so it is important to properly evaluate the consumption of hot and cold water. In that process, load-survey is most effective way to inquire the actual volume and heat. But many times it is difficult to compare one data with another because each data usually depends on the temperature of cold and hot water, which change by seasons, regions, and supply sysytems. In this paper, we surveyed consumption of hot and cold water in 10 houses in apartment-house on Hyogo prefecture. To get rid of influence of cold water's temperature change, we introduce the evaluation method besed on volume and heat of mixed-hot-water on faucet. Through comparison between questionnaire and surveyed consumption arranged by that method, we could find good relation between residents' usage and difference in houses, each houses' annual change difference of hot water volume and heat. So we can recommend to arrange surveyed data by this method to make comparison between each data easier and to find out relation between actual usage and residents' behavior.

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This study determined the heat of evaporation of 1,4-dioxane aqueous solution, which is necessary to plan the absorption-type refrigeration cycle using the working medium developed by the authors and to establish a method of estimating it based on the existing forms of both components of 1,4-dioxane aqueous solution. Heat of evaporation at constant pressure (101.35kPa) and molar fraction dependency were measured and calculated during both the evaporation process in which the vapor-liquid composition remained constant and the process in which the composition changed, in consideration of the liquid structure of 1,4-dioxane aqueous solution. The measurements and calculation results were compared with existing heat of evaporation data and led to the following results: (1) The mean difference in heat of evaporation was 2.07% between the value calculated using calculation software (UNIFAC method) that simulated a certain amount of evaporation in vapor-liquid equilibrium at low pressure and the value determined by experiments. (2) The mean difference in heat of evaporation was 3.35% between the value determined from total evaporation using TG-DSC and the value calculated from the approximate expression of the relation between cumulative heat of evaporation of partial heat of evaporation and cumulative sample evaporation. (3) The mean difference in heat of evaporation between the value calculated as molar fraction means of both components of the simple mixture model and (1) or (2) was 2.55% and 3.41%, respectively. In conclusion, the heat of evaporation of 1,4-dioxane aqueous solution can be estimated as molar fraction means of both components of the simple mixture model as an ideal mixture of normal liquid.

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This paper reports the assessment, through measured-data analysis, of a commercial-use air conditioning system made up of an exhaust heat recovery heat pump and a newly devised rectangular thermal storage tank for simultaneous storage of warm water and ice. Through a bubbling test, the authors analyzed the system's summertime operation data, when its ice thermal storage mode was fully in service, revealing the effectiveness of bubbling during thermal-storage and discharge operations. Further, the system operation data collected over a two-year period showed that the devised system has a superior nighttime-shifted thermal load factor as well as high thermal efficiency, highlighting the devised system's excellent energy conservation effects and cost-performance.

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Restraining the algae growth and slime formation in cooling tower is very important for the maintenance of the function of circulatory water system. In this paper, we proposed a new method (technology) which can be used for established cooling towers. The characteristics of this new method (technology) is to paint a new type of coating mixed with organic adhesion agent and photocatalysis powder on the water-spreading pan of cooling tower. The function of photocatalyst is to restrain the algae growth and slime formation. On the other hand, the organic adhesion agent will gradually decompose from the surface, so it can remove precipitated scale and deteriorated photocatalyst coating surface when it decomposes and make new photocatalyst under deteriorated photocatalyst to activate. Investigation and evaluation on effect of the new type of coating were carried out in 17 working cooling towers. It was showed that the new type of coating could effectively restrains the algae growth and slime formation on certain condition of duration of sunshine and depth of water.

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Based on a huge number of schedule data on inhabitants' behavior and state transition probability functions relates to cooling switch on/off that are obtained by authors in the earlier works, a series of numerical experiments is carried out, where dynamic characteristics of maximum and seasonal cooling requirements are mainly focussed on. One of the most significant results is the fact that the daily varying schedule data have significant influence on the maximum load if you shed some light on total maximum load for a set of dwellings, holistic mass of dwelling block and dwelling area.

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The optimal design method of indoor thermal environment using CFD coupled simulation (hereafter CFD) is developed in this study. CFD could analyze the thermal environment considering the distribution of temperature, velocity, etc. in a room. It would be therefore appropriate to use CFD for the optimal design method considering their distributions. In this paper, the optimal design means the most appropriate boundary conditions of the room (e.g. the types of HVAC system, the location of supply inlet, etc.) among the conditions where the design target of indoor thermal environment is achieved. The optimal design method using CFD could be divided into two categories. One is the design method including the feedback system which modifies the boundary condition of CFD according to decision-making models by a designer. The modification of boundary conditions could extend to the positions of air exhaust outlets and supply inlets and also to the positions and their scales of windows. The other is the searching system of finding the optimal design among the systems with possible boundary conditions. In case of the former feedback system, since CFD coupled simulation has high calculation load, it was hardly possible to practical use as the optimal design method. In this paper, the latter optimal design method using CFD is proposed. It includes the Genetic Algorithm (GA) for searching the optimal design. This method has two steps. In the first step, the GA and a simple indoor environmental analysis, which does not use CFD, are used for obtaining the potential candidates for the optimal design. About 10-20 candidates are selected from the GA system. In the second step, the thermal environments of the potential candidates are analyzed by CFD coupled simulation. To examine the performance of this method, the optimal design of hybrid ventilation system, which uses the natural cross ventilation and the radiation-cooling panel is conducted. In this study, the thermal environment is evaluated using the thermal sensation of a human, the energy usage of the radiation panel, and the temperature difference of a room. Using this method, the optimal locations of the radiation cooling panel and the supply inlet of the ventilation, the shape of a room, the surface temperature of the radiation panel, and the shape of the radiation panel are analyzed and optimized.

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This study aims to develop the high-accuracy analysis method of radiative heat transfer that can be used for a coupled simulation of convection and radiation. The method is demonstrated by applying it to the thermal environment around a human body with a realistic shape and size. In the previous paper (Part 1), the method to calculate radiative exchange coefficients (direct interchange areas) and the method to compress the storing capacity of the total exchange areas by grouping some solid surface elements into one larger segment were reported. A naked human body model in standing posture with a realistic shape and size was also created. In this paper, the projection area factor and the effective radiation area factor of the human body model was calculated and compared with Fanger's experimental results. Then, a coupled analysis of convection and radiation was made for the case that the human body model was situated in the center of the room with no ventilation. The low-Reynolds-number type k-ε turbulence model was employed for the fluid analysis. Furthermore, influence of the grouping procedure of solid surface elements on the calculated results was investigated. The calculated results given by the use of grouped segments having 1345 elements (segments) were in good agreement with those given by using the original 8942 elements except parts of eye sockets and nose that are having uneven shapes. It should be noted that the storing capacity of the total exchange areas was appreciably reduced to 2.3% of the original one. The evaluation of accuracy of the method will be reported by comparing the experimental results using a thermal manikin in Part 3.

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In the present study an optimal operation scheme of an HVAC system is proposed and the test results applied for a real office building are shown and investigated. The scheme is divided into two steps; the first is to identify the parameters of the mathematical models of each HVAC component such as fan, pump and heat pump, and the second is to optimize total energy consumption of HVAC system operation. The feasibility of the proposed method was tested using a real HVAC system of an office building and the following results were obtained: 1) parameter identification can be achieved successfully. 2) Small errors in the model performance were found at some operating points, however, optimal. operation with about 13% energy conservation was able to be attained by the present method as a whole.

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The purpose of this research is to estimate the antibacterial and antifungal activity of air conditioning filters treated with hydrolase or pyridine which is one of the most prevalently used antibacterial and antifungal agents. Moreover, the influence of the concentration of pyridine and media used for antibacterial test was examined. From these results, both of air conditioning filters were effective to control the growth of bacteria and fungi under the environment with few nutrient sourses for bacteria and fungi. But under the environment with a lot of nutrient sourse, the effect of these filters were limiting. Consequently, both of air conditioning filters may not sufficient to prevent the growth of microorganism under the environment with heavy contamination such as house dust et al. We thought that it is need to improve the antibacterial and antifungal activity of air conditioning filters used in this study.

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An optimum control of heating and cooling plant with thermal storage tanks comes to essentially large-scale mixed integer programming problem. It is very difficult to obtain the optimum solution of such problem in a short time enough to control the plant on real time. Here, we proposed a practical method to get approximate solution of the large-scale mixed integer programming problem in a short time. The method consists of two steps; that is, at the first step, the mixed integer programming problem is simplified to a linear programming problem excluding some nonlinear factors and the simplified linear programming problem is solved using two phase simplex method. At the second step, the optimum solution obtained at the first step is modified to satisfy the real condition by taking the factors excluded at the first step into consideration. Simulation of operation of a real plant showed that our practical method was effective to reduce the running cost of heating and cooling plant.

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Albedo value in Osaka city was computed by using LANDSAT/MSS satellite data. When building coverage exceeded 0.3, albedo value was a constant of 0.12 regardless of building height, and had the convex curve with the minimum value at 0.35 of building coverage. When building height was less than 10m, albedo value varied widely. However when building height was larger than 10m, albedo value decreased slightly regardless of building coverage. Next albedo value was calculated by using urban canopy model. Albedo values obtained from both LANDSAT/MSS satellite data and urban canopy model agreed reasonably. This result suggested that urban canopy model was accurate.

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