The Ventilation Standard HASS 102 recommends the ventilation design, which takes into account a ventilation effectiveness in an occupied zone, under the incompletely mixed condition. This index is called Normalized Concentration in an Occupied Zone (Cn), which defined as the ratio of the difference between the average pollutant concentration in an occupied zone and that of the completely mixed indoor air. In this research, Normalized Concentration in an Occupied Zone in office space (10m(x)×3m(y)×3m(z)) is analyzed using the ventilation effectiveness indices of Visitation Frequency (VF; frequency of contaminant returning back to an objective domain) and Purging Flow Rate (PFR; air flow rate of a local domain based on the domain averaged concentration). In this paper, the partitions and desks are installed in the occupied zone of office space. In this paper, the relationship between VF, PFR and Normalized Concentration in an Occupied Zone (Cn) are methodically analyzed. 3 cases of ventilation system were set where the thermal boundary conditions ((1) cooling condition in summer season, (2) cooling condition in winter season, (3) heating condition in winter season) are changed respectively. In the numerical analysis, changes in the property of Normalized Concentration in an Occupied Zone (Cn), are analyzed by VF and PFR in detail. The effects of the increment of return air, which induced in a supplied air, are also studied. In this analysis, while VF values of occupied zone were exponentially increased, Normalized Concentration in an Occupied Zone (Cn) got closer to 1.0 (the concentration of the completely mixed indoor air) for the increment of return air in supplied air.

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Electric power generation performances differ by whether air is supplied to a solid high polymer film type fuel cell, or oxygen is supplied. The reduction method of the equipment capacity of the fuel cell system of having used this characteristic is considered. When electricity demand is small, a part of electric power generated by the fuel cell is supplied to a water electrolysis device, the hydrogen and oxygen which were generated by the water electrolysis are compressed, and these store in each cylinder. On the other hand, when electricity demand is large, both gases are supplied to the fuel cell system and generated. To load change of electricity demand, in this paper, as described above, the fuel cell system in consideration of reduction of fuel cell capacity is operated. If this method is introduced into the local energy network constituted from individual houses, a hospital, office, etc., it will be estimated as what becomes 36% of capacity reduction to the conventional system.

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Existing personal air conditioning (PAC) cools only specific portions of the body in the form of spot cooling using cooled or fast air flow. This encompasses various problems concerning comfort due to localized air flow causing discomfort to the face and neck areas, and dryness to the eyes. This research proposes a new task air-conditioning method to control the task area by minimizing the temperature and airflow distributions and allowing the human thermal environment to be as regular as possible, as well as preventing the human body in the task area from being exposed to a largely irregular thermal environment. This is termed a "task area wide-cover type personal air conditioning method" here. This refers to a method of air conditioning in which cooled air blown upward from a PAC unit is allowed to fall over a wide task area including the human body due to the difference in the density of the cooled air, and this minimizes the drafts. We used the PIV (Particle Image Velocimeter) and the coupled simulation of convection and radiation to examine the airflow fields for conventional spot-cooling and task area wide-cover type PAC around the human body, aimed at confirming the effectiveness of wide-cover type PAC. The wide-cover type PAC formed a calm air flow field of less than 0.18m/s around the human body, while the spot cooling type PAC formed an air current of 0.3-0.6m/s around the area of the neck. In the case of the wide-cover type PAC, the distribution of the clothes surface temperature and convective heat transfer rate etc. of the human body is smaller than in the spot-cooling PAC.

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For design of thermal storage and operation control of HVAC system with thermal storage tank, a prediction method of thermal mixing behavior in the storage tank under operating condition is required. In this paper, a mixing model for temperature-stratified thermal storage tank is presented. The mixing model is modified from the mixing model which is based for the conditions that input water temperature and flow rate are kept constant and the initial temperature in the storage tank is uniform. Our mixing model is applied to numerical calculation for water temperature in the thermal storage tank under variable input conditions such as actual operation conditions. And three parameters which are included in the mixing model were identified from experimental results with variable input conditions. The Experiments were performed by using two equipments with different sizes of thermal storage tank. It was found that calculated results by using the mixing model are agree well with the experimental results with variable input conditions.

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The purpose of this study is to clarify the relation of thermal exchanging characteristic and COP in split type air-conditioner, through survey and CFD. And in case that outlet-air short-circuited, we studied how COP changed. So, We investigated the COP of air-conditioner by gathered data through survey in the office and performed CFD analysis. And then, we calculated COP expected for improvement from thermal exchanging characteristic. As a result, COP of split type air-conditioner is 3.14, in case of setting up room's temperature with the open air (32℃) and the humidity (68%). Second, through CFD, it was grasped how air fluid situation constitutes. Third, in case of changing an angle of outlet-air from air-conditioner (30°, 45°, 60°), when COP of 45° setted a standard, it was favorable by order of 45°30°, 60° from a short-circuited point of view

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As global environment problem has become an important issue, ammonia refrigerant has been watched with keen interest because it does not cause destruction of the ozone layer and global warming. We have developed an air-source and water-source heat pump units using ammonia refrigerant with ice thermal storage tank from perspective for popularizing systems which use natural energy and natural working fluids. To further popularizing of this system, we have to verify its reliability and safety because ammonia refrigerant is prescribed for toxic and combustible gas in ammonia gas regulations in Japan such as Fire Code, High Pressure Gas Control Code and Industrial Safety and Health Code. In this report, aiming to rationalize of its design, operation and maintenance, we carried out practical study to verify its performance both in development phase and aging change, and results of the field test for verification of its performance are presented. It was found that the heat pump unit using ammonia refrigerant can be handled as well as the heat pump unit using fluorocarbon refrigerant such as HFC. Thus the reliability and safety of this heat pump unit using ammonia refrigerant was verified.

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Energy Service Company (ESCO) is expanding as a means of energy savings in industrial field in Japan. ESCO Performance Contract periods are mostly 10 years. For these long-term periods, utility costs such as fuel and electric prices will vary depending on imported crude oil and liquefied natural gas. These prices will affect ESCO profit yearly. Especially, the fuel costs make up sixty percents of the project costs in the case of ESCO which introduces mainly co-generation system, therefore it is essential to reduce fuel prices fluctuation risk, to maintain the ESCO profit as stable. We examined a way of making use of derivatives to reduce fuel prices fluctuation risk on practical plants, and picked out guidelines for derivatives. Moreover, we have developed a simulation tool to analyze ESCO profit fluctuation easily, and applied to the practical ESCO project plants. As a result, most stable fixed rate of fuel consumption used by co-generation is between 5 to 50 percent.

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Many air-conditioning systems adopt absorption chiller-heaters as heat source equipment and the remote observation systems for these machines have recently been spreading. Fouling in the cooling water tubes of this equipment is a critical problem that degrades performance, and it often causes abnormally high pressure in the high temperature generator and emergency shutdowns. In this paper, we discuss a new diagnosis algorithm for fouling that we developed for a remote observation system. This algorithm is based on the results of dynamic simulation on the absorption cooling cycle, so it can be applied to transient data such as ON/OFF operation in the intermediate period. Since the dynamic simulator computes the behavior of various models, this method of diagnosis can be applied to many chiller-heaters from the older to present models. This algorithm takes the dispersion of each chiller-heater into account through individual and successive trend monitoring. The results of the diagnosis test revealed increased fouling and the quantitative effect of tube cleaning. We successfully applied the new algorithm to a remote observation system that monitored approximately 4,500 absorption chiller-heaters.

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The purpose of this study is to develop a new calculating method for water supply demands in restaurant. It is difficult to clarify the characteristic and to estimate the volumes of water supply demands in each faucet and cooking equipment in restaurant because the water usage is various and complicated in each operation or cooking equipment. However, it is possible to easily get the data of water consumption in a whole kitchen and to clarify the characteristic of water supply demands of the whole kitchen. The authors have advanced the development of calculating method for the time series loads, such as a daily, hourly and instantaneous loads by using a computer. We have proposed the method that applies the unit model as the water consumption of one flat in an apartment. Applying the view of a unit model, it is possible to prospect the loads of water consumption in restaurant. In this paper, the measurements of water consumption were carried out in 21 restaurants, and the basic data on the store characteristics were offered by a management company. First of all, the method of the numerical analysis for a large data recorded the volumes of water consumption in every one- minute over a year was studied. Secondly, the relationship between number of customers and hourly water supply demands was analyzed. In addition, analyzing the measurement data of water consumption, the calculating unit model of water usage in the kitchen was set up. The time series loads in the restaurants were calculated by using the method that applied the Monte Carlo simulation technique, and the precision of results were studied as a comparison with the measurement data. As the results, it was shown that the calculating method was effective in restaurants.

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The final purpose of this study is to expand the application range of the flow capacity prediction method of the special drainage fitting systems into the case of complex piping layout which exist in the actual apartment houses. In this paper, for the first step, we carried out the drainage load test with three kinds of the special drainage fitting systems, changing the piping layout of the drainage stack or the house drain. And we investigated the behavior of the air flow quantity and the air pressure in the drainage stack by change of the piping layout. As a result, it was found that the air flow quantity and the air pressure in the drainage stack change with piping layout, but experimental coefficient k (subtract the mean air pressure from the minimum & maximum air pressure, and divide by the standard deviation of the air pressure) is almost constant.

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The reduction characteristic of turbulent drag and heat transfer of drag reduction surfactant solution flowing in a helically coiled pipe were experimentally investigated. The drag reduction surfactant used in the present study was the amine oxide type nonionic surfactant of oleyldihydroxyethylamine oxide (ODEAO, C_<22>H_<45>NO_3=371). The zwitterion surfactant of Cetyldimethylaminoaciticacid betaine (CDMB, C_<20>H_<41>NO_2=327) was added by 10 percent to the ODEAO solution in order to avoid the chemical degradation of ODEAO by ionic impurities in a test tape water. The experiments of flow drag and heat transfer reduction were carried out in the helically coiled pipe ofcoil to pipe diameter ratio of 37.5mm and the helically coiled pipe length to pipe diameter of 1180.5.mm (pipe diameter of 14.4mm) at various concentrations, temperatures and flow velocities of the ODEAO surfactant solution. The ODEAO solution showed a non-Newtonian behavior at high concentration of the ODEAO. From the experimental results, it was observed that the friction factor of the ODEAO surfactant solution flowing through the coiled pipe was decreased to a great extent in comparison with water as a Newtonian fluid in the turbulent flow region. Heat transfer measurements for water and the ODEAO solution were performed in both laminar and turbulent flow regions under the uniform heat flux boundary condition. The heat transfer coefficients for the ODEAO solution flow were the same as water flow in the laminar region. On the other hand, heat transfer reduction of the ODEAO solution flow was remarkably reduced as compared with that of the water flow in the turbulent flow region.

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