In the past, there was the constant temperature clean room composed of the air conditioner that used cooling water, heat wires and hot water as heat-source. However, they are not considered about the energy-saving and system running cost. We made a constant temperature clean room for a semiconductor manufacturing process, in which the room temperature is controlled every minute. This clean room system was composed of a clean room insulated from temperature variation in the outside environment and an air conditioner that used only cooling water as heat-source to control the clean room temperature. The air conditioner was composed of double cooling water circulation, a cooling coil, and a heat exchanger. Analyzed the experimental data of clean room temperature, temperature in the environment, cooling water temperature around cooling coil, and cooling water temperature around heat exchanger in the air conditioner. And we calculated spectrum of temperature variation data to estimate the energy of temperature variation, and cross-correlation function between each temperature variation data to investigate the cause of clean room temperature variation. As the result, we knew that the clean room temperature variation were significantly effected by the supply cooling water temperature variation. Furthermore, the air conditioner composed of triple cooling water circulation and double heat exchangers to reduce the clean room temperature variation. And the same analysis as above was followed. As he results, it was considered that it was important to increase the number of cooling water circulation for controlling the clean room temperature variation minutely, and this system realized to make the clean room temperature variation less than about ±0.01 degree.

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Building materials used indoors usually emit organic compounds into the interior space. It has been emphasized to reduce the exposure rate of humans to indoor air pollutants and to improve the quality of indoor air by the use of less polluting materials. Small-scale chambers have been used to develop emission rate data of volatile organic compounds (VOC) and formaldehyde. These tests involve placing samples in the chamber and measuring concentrations at various times. The concentrations versus time data are used to determine the parameters of emission rate models. The purpose of this study is to estimate long term formaldehyde emission rates emitted from lauan plywood using empirical regression models.

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The purpose of this study is to establish the prediction methods for the cooling, heating and electric loads on district energy supply systems by means of the analysis of existing operation data. The load prediction is indispensable for the planning, introduction and operation of the energy plants and stations. This paper examines the correlation between the weather data and daily maximum or hourly loads of steam and hot water, which are essential to the estimation of the thermal loads of DHC (District Heating and Cooling) plants and CGS (Co-Generation System) stations. As the results, the daily maximum thermal loads depend on the average outdoor air temperature during the building operation time zone. The hourly thermal loads can be predicted using the outdoor air temperature at that time. The comparison of two regional and yearly different data confirms the versatility of the proposed prediction methods.

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We examined a combined reuse system of used or scrap tires for thermal storage and activated charcoal. Activated charcoal can be generated together with heat generation in a boiler for used tires. We carried on researches into adsorption properties of activated charcoal for several kinds of harmful odorous substances, sulfuer dioxide and nitrogen oxides. Firstly we performed experiments on cleaning ability of activated charcoal for harmful odorous gases using synthetic lipid membrane odor sensors. Second one is about adsorption properties of activated charcoal and combination of water content for pure SO_2 gas at room temperature level. We also performed the examinations for SO_2 and NO_x of ordinary combustion gases with a stove. Finally we carried out the experiments on reduction effects for SO_2 and NO_x produced inevitably in combustion process of used tires at a real facility equipped a boiler for used tires. We drew up guiding principles of utilization of activated charcoal generated from used tires.

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In order to accurately evaluate the dynamic behavior of HVAC system, it is necessary to use dynamic simulation program with accurately verification. In the present paper, the reproducibility of a dynamic simulation program called HVACSIM^+(J) was verified by comparing the actual measurements and simulated results in two kinds of states, normal and fault, for a HVAC system with single duct and constant air volume. As the result, it was verified that the program could reproduce the dynamic behavior of the system with sufficient accuracy, if users correctly input characteristic values of the real system and properly adjust some parameters in the component model as well.

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In this paper, the outline of our PIV technique for low-velocity-airflow measurement using visualized images with smoke particles was introduced, and the characteristics of this technique was inspected by applying it to simulated visualized images of the flow for standard images prepared by The Visualization Society of Japan. From the inspection, the following characteristics were confirmed: 1) Smoke images are inferior to particle images in the accuracy of measurement, and the visualization to obtain fine pattern of tracer concentration distribution is essential to improve the accuracy. 2) The error of vector extraction can be reduced by introducing the safety factor to the threshold in the successive abandonment algorithm. 3) The deterioration of the performance due to the use of field images obtained through interlace scanning of conventional cameras is small in smoke images compared with particle images. The technique was tried to apply to the measurement of an unsteady airflow past a plate. The movement of Karman vortex toward the dawn stream was observed clearly in the result, and the technique was confirmed to be applicable also to unsteady flow.

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Recently, wooden houses in Hokkaido have become more airtight. As concern for indoor air quality has grown, so too has the need to measure interzonal airflows in houses to assess the distribution of outdoor-air and of interzonal airflows. Outdoor-air volume and interzonal airflows between rooms can be usually calculated by measuring concentration of tracer gases in each room. Traditional Japanese houses make the best of convection ventilation for comfortable living in summer, so that a lot of warm air at the ceiling level is smoothly exhausted. In this paper, exhausted quantity of warm air and inflowed quantity of cool outdoor-air through the opening of the upper levels in a test house well were measured throughout the day by using a portable gas chromatograpy analyzer and by dosing four kinds of tracer gas. 1) By using the step down method and the impulse injection method in advance, modeling of the test house for airflow paths could be imaged as 2-zone model and as 4-zone model. 2) In case of 2-zone model, exhausted quantity of warm air and inflowed quantity of cool outdoor-air through the upper opening in the test house well were measured throughout the day while the tracer gases have been continuously dosed. 3) In case of 4-zone model, interzonal airflows between four rooms according to the buoyant convection were measured throughout the day in summer while the tracer gases have been continuously dosed. 4) Inflow ratio of outdoor air could be calculated throughout the day as variable under changes in the wind velocity and in the difference between interior air temperature and exterior air temperature.

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The purpose of this study is to understand the co-efficient of performance (COP) on the partial load of energy source equipments by the result of measurements of a middle scale office building with a thermal storage tank. The result of the air-conditioning load measurements indicates to be much operating time at the partial load. In order to reduce the energy consumption and running cost of the air-conditioning energy source systems, their systems should be selected for the hi-performance equipment not only on the peak load, but also on the partial load. This paper reports the measurement data of the COP of air source heat pump chiller-heater, and analyzed the relation with COP and effecting factors. This paper shows the formula of COP for the simulation, and confirms the correctness of this formula. And also this paper reports the heat loss ratio of thermal storage tank in a year.

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Characteristics of wet-gas absorption system with clean water was studied by experimental method. The system was composed of hollow cone type spray nozzles and special eliminator with hydrophilic walls. These nozzles were placed 200mm apart in rectangular duct. The clean water was supplied to the spray nozzles and eliminator. Absorption of NH_3 and SO_2 was measured on various conditions. It has become obvious that the estimation of gas absorption efficiency is possible by pH value in aqueous phase at the exit of the wet-gas absorption system. The special eliminator was constructed of layers of corrugated channels. Characteristics of friction factors and mass transfer of the eliminator were also investigated for different two shapes of the corrugated channel. Gas phase mass transfer characteristics of the eliminator was measured about the Reynolds number range between 1000 and 7000. The Reynolds number dependence on the friction factor is very little change and average Sherwood number for these eliminators is proportional to Re^<0.75>.

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The exhaust heat from air conditioners is one of the main factors contributing to the heat island effect in urban areas. This study, taking an approach based on environmental load of the urban atmosphere, used numerical analysis to clarify heat discharge characteristics of air conditioning systems. First, typical air conditioning systems used in offices were classified based on construction and utilities data, then data were collected on coefficient of performance (COP) of those systems' heat sources and correlated. Next, an office building was hypothesized and the summertime air conditioning load was derived to estimate the energy consumed and amount of heat discharged by air conditioning systems, and system COP. The results were as follows: 1) The value of system COP was greatly affected by air temperature and sectional load in multi-systems for buildings, but it was relatively stable in the case of systems using heat and chilled water generators. 2) The cooling load of multi-systems for buildings accounted for 75% of sensible heat emitted by air conditioning systems, but in the case of systems using heat and chilled water generators sensible heat emitted was almost entirely caused by energy consumption by air conditioning systems. 3) Most of the heat emissions from cooling towers were in the form of latent heat, with very little sensible heat. However, to evaluate sensible heat, it is extremely important to estimate the temperature of the coolant. 4) The COP of multi-systems used in buildings decreased as the temperature went above 25℃. With an increase in cooling load came a very large increase in the energy consumption for air conditioning. 5) Artificial heat consumed by medium-rise office buildings was more than 66% the quantity of solar radiation; in the case of multi-systems for buildings, almost all was discharged in the form of sensible heat, meaning that its effect on the atmospheric environment cannot be ignored.

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