A flow resistance of flow drag reduction surfactant water solutions could be reduced considerably by adding a small amount of the surfactant to the heat transfer fluid. And surfactants also lead to reduced overall heat transfer coefficient compared to those of pure water, too. So a recent application of drag reduction effect is to reduce the pumping power in the district heating and cooling systems. However, most of the previous experimental studies of drag reduction effect have been confined to straight pipelines. In this paper, the flow and heat transfer characteristics of water solution with the surfactant flowing in a shell tube type and plate heat exchangers have been measured under various experimental conditions of mean velocity and solution temperature. And it was found that the flow resistance and heat transfer of the surfactant water solution flow in these heat exchangers were greater than those in the straight pipes. However, the flow drag reduction rate and the modified Reynolds range in the plate type heat exchanger were less than those in the shell tube type heat exchanger. And in the plate type heat exchanger, the heat transfer reduction rate was greater than the flow drag reduction effect. The performance of these exchangers have been evaluated by investigating both the temperature efficiency and the pumping power rate.

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For prevention of airborne molecular contamination in semiconductor manufacturing factories, the effects of air conditioning temperature and exposure of high-concentration toluene on the generation rate of organic compounds from cleanroom surfaces are studied. The organic compound concentration in cleanroom air increases after changing the air conditioning temperature to 33℃ from 23℃, and decreases when the temperature is brought back to 23℃. This decrease is considered to be caused by adsorption of low-boiling-point compounds to the surfaces. Toluene is adsorbed on the surfaces by an exposure of high-concentration toluene, and the rate of toluene generation thereafter from the surfaces is found to correlate with ventilation time by outdoor air and with the quantity of toluene exposure. The rate constant and activation energy of desorption for toluene from cleanroom surfaces are determined at 23℃〜33℃

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Most gymnasiums belonging to schools and other public buildings are used for assembly as well as for indoor training. When a gymnasium is used for assembly, the occupants are supposed to be various kinds of people, such as children, elders and handicapped people etc. Therefore the installation of an appropriate HVAC system is required in such gymnasiums. In this paper, the heating system and indoor conditions in a gymnasium are examined with a field study and numerical simulations. The field study in a gymnasium with a heating system was carried out in winter in order to know the actual condition, such as vertical temperature distribution and airflow pattern of supply jet. Based on the result of the field study and previous studies, seven types of heating system with various layouts of supply/exhaust openings and angles of supply jet were selected and studied by numerical analysis. In the macroscopic model simulations, the vertical temperature distribution and the heat load were predicted for each type of heating system. Microscopic simulations (CFD, Computational fluid dynamics) were conducted on the five heating systems that were found to have good efficiency by the macroscopic model. In the microscopic simulation, the details of airflow pattern and temperature distribution were examined and the selection of appropriate heating system in a gymnasium was discussed.

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A methodology to generate a huge number of schedule data on inhabitants' behavior is established. Original data come from Field Survey on Living Schedule of National People obtained by NHK in 1990. This kind of data set having numerous samples give us various advantages when we discuss an absolutely accurate maximum load and stochastic thermal load, which seems to be one of the important viewpoints in designing system capacities. This paper indicates the initial first step by presenting a practical method based on the original data set labeled as "workingmen/on weekdays". Also a discussion of its plausibility is shown.

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In order to design the thermal and humid indoor Climate by using condensation and evaporation phenomena on the surface of waterfall in a large well, the relationship between the condensation rates and the boundary condition, i.e. air velocity, vapor pressure and relative humidity, was found by experimental results from a small model. At the same time, the mechanism of evaporation on the surface of waterfall was discussed as the measurement results by the same analysis method. The following conclusions were drawn from the results of this study. 1) As the air velocity and the difference of vapor pressure increase, the condensation rates on the surface of waterfall increase. As the relative humidity decreases, the condensation rates decrease. The above relationships were approximated by using the least square method. 2) In a rough estimate, the dehumidification factor corresponds to the convective heat transfer coefficient. The condensation rates by the waterfall are larger than that of the running water of a pond. 3) If the cool waterfall is designed in a large well, the condensation rates will be estimated by using the above relationships in advance. So the thermal and humid indoor climate in a large well will be improved by the condensation phenomena

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To evaluate heat-load in apartment houses, it is important to assume the application of heating equipment by inhabitants. We studied on usage of heating in apartment houses in Tsukaguchi, Hyogo-pref. First, We found 4 standard patterns of heating time-zone from questionnaire collected from all houses. Then, by analysis of energy consumption of heating in 7 selected houses, we found that in most case, heating is used on inhabitants awake time zone, and usually heating is applied when outdoor air-temperature is under 18℃. It might be useful to determine the condition of heating application in simulating heat-load.

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In this paper, a procedure was proposed to verify the effect of energy conservation retrofit of existing buildings. The procedure was applied to the actual retrofit project of a building and was proved to be practical. The following is the outline of this study. 1. The procedure to estimate and verify the effect of energy conservation retrofit (1) Primary energy consumed in "core time", which is between 8:00 and 18:00 during weekdays, shall be used to evaluate the effect of energy conservation retrofit. (2) Before the retrofit construction, based on the operational record and short term measurement, if necessary, the amount of primary energy consumed in "core time" per year shall be presumed. Based on this energy in "core time", the amount of energy consumption per month for each use, such as air-conditioning, lighting, hygiene, elevator etc., shall be obtained by calculation. (3) Considering the effect of energy conservation techniques to be adopted in the retrofit of the building, the amount of energy consumption per month for each use per month shall be estimated by calculation. (4) After the retrofit construction, the amount of energy consumption for each use shall be measured and compared with the estimated data. (5) The amount of energy used for air-conditioning shall be adjusted considering the effect of operational conditions, such as outside air temperature, indoor air temperature, heat generation due to lighting and other equipment, and number of occupants in the building. 2. Results of application of the procedure to the actual retrofit project (1) An actual retrofit project aimed at energy conservation was selected and the procedure mentioned above was applied. (2) Based on the operational record and the measurement of one month term, the amount of primary energy consumed in "core time" per year was estimated to be 1679MJ/m2year. The amount of energy consumption in "non core time" was about 13% of that in "core time". (3) The amount of energy consumption after the retrofit was estimated to be 1314MJ/m2year which is 21.7% less than that before the retrofit. (4) After the retrofit construction was finished, the amount of energy consumption per month for each use was measured for three years and compared with that estimated before the construction. (5) Energy consumption used for air-conditioning was adjusted considering the operational conditions. The amount of energy adjusted was about 3% of the measured data. (6) After the adjustment of energy used for air-conditioning, the effect of energy consumption was determined to be 23.6%, 27.9%, and 33.5% in the first, second, and third year consecutively after finishing the retrofit construction. The verification method mentioned above was proved to be practical enough.

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The experimental results on the cooling load of a large space using a two dimensional 1/4 scaled down model are described. Comparison was made on the vertical temperature distribution and heat load among the cases of overall air conditioning and occupied zone air-conditioning. Two different types of experiment were made, The set point temperture of occupied zone was controlled by inlet temperature in Experiment I and by inlet air volume in Experiment II with and without internal heat generation. From the measured results of vertical temperature distribution it was found that occupied zone air-conditioning cooled the space of 3m or more above the floor level when internal heat generation was increased. It was found that the energy-saving effect by occupied zone air-conditioning could amount to about 30% or more and increased as inlet air velocity was small. The vertical temperature distribution expressed by 2-dimensional airflow pattern in this model experiment agreed quite well with the simulation results. The two adjacent guard spaces used were considered effective in reproducing the 2-dimensional air flow patterns.

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