In the method of horizontal air supply at the bottom of fancoil unit (HASB) in air conditioning system, as far as the occurrence of the short circuit phenomena and draft can be avoided by devising of air supply conditions, the supply air temperature can be lowered and thermal energy can be saved at the same thermal environment, compared with the method of vertical air supply at the top of fancoil unit (VAST). In this paper, under the thermal environment criteria of average temperature of 20℃ and average PMV of 0 (neutral) in an occupied zone, the steady state numerical calculation of HASB was conducted for a model room equivalent to that used in the past experiment. The optimum air supply conditions were discussed based upon the results of environmental factors such as heat loss through wall, supply air temperature, suction air temperature and temperature factor. As results, in some cases of the suitable combination of air flow rate and width of air outlet, the optimum scope where the supply air temperature and heat loss through wall can be minimized, was found. Furthermore, it was shown that the environmental factors except supply air temperature could be arranged by Archimedes number roughly.

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This study describes on the investigation and analysis of air-conditioning automatic control facilities by the periodical inspection data. We discussed quantitative tendencies and characteristics for reliability and maintainability. So this report analyses 96121 cases by the periodical inspection data on 250 building in the Tokyo area. This investigation was conducted in 1990 by the periodical inspection data. In this paper, we clarify quantitative tendencies and characteristics for reliability and maintainability under the following classification. 1) Application of building 2) Building facilities system 3) Age-based trend 4) Defective Ratio 5) Unit accessibility It's shown that these results are very useful in the field of maintenance.

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In measuring atmospheric asbestos fiber concentration, a specimen for phase-contrast microscopic observation is usually prepared with the Membrane Filter Method. In this method, the sampling rate is restricted to be very low owing to high pressure drop through a filter. Moreover, as the total volume of the sampling air is restricted to be low to obtain a clear specimen, the number density of asbestos fibers per unit area in a specimen is also usually low, and it may lead to noticeable errors in a measurement. If the total volume of sampling air exceeds an adequate value, a specimen is contaminated with fine particles and non-asbestos fibers which are contained in the atmosphere. In this paper, the specimen-preparation technique combined with the aerosol sampling with a four stage cascade impactor and the removal of non-asbestos fibers with heat and acid treatment was proposed. The cascade impactor was equipped with four nozzles of the same segregation diameter to eliminate fine particles from the specimen. The segregation diameter of each stage was determined by assumption that the shape of fibers was ellipsoid. The advantages of this method compared with the Membrane Filter Method are as follows: 1) The sampling flow rate is higher. 2) A specimen with a higher density of asbestos fibers and fewer fine particles is obtained. 3) The elimination of non-asbestos fibers with heat and acid treatment can be executed since fibers and particles are collected on a cover glass instead of a filter paper. The average collection efficiencies of the cascade impactors for chrysotile, glass fiber and atmospheric fibrous dust were 95.9%, 95.0% and 95.8%, respectively. Heat and acid treatment to eliminate non-asbestos fibers were also developed. Synthetic fibers (e.g., nylon and so on), botanical fibers (e.g., cotton and so on) and faunal fibers (e.g., silk and so on) generated in daily life were eliminated with heat treatment. Mineral fibers, however, were not eliminated with heat treatment because of their high heat-resistance. Mineral fibers such as rockwool and glass fiber were eliminated with acid treatment using one normal solution of hydrofluoric acid. This treatment did not affect chrysotile, amosite and crocidolite fibers.

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The popularization of cooling devices for homes is giving a serious influence on the energy consumption during the summer. We have conducted some surveys about housing energy consumption in Kyushu. This paper describes the energy consumption of detached and apartment houses with the latest information that was compiled during hot and humid summer season in Fukuoka city with the following aims. 1) To verify a method that predicts the amount of energy consumption in six uses (for cooling, heating, hot water, cooking and lighting and the other), and to examine the results. 2) To understand the rate of popularization, using condition and energy consumption of housing equipment tools. 3) To grasp the time series variation of energy consumption and life styles on a holiday and a weekday. 4) To evaluate Fukuoka's characteristics on the housing energy consumption in comparison with the other areas in Japan on the basis of literatures.

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This study aims continuatively to the suitable planning and operating conditions for small scale household wastewater treatment facilities with biological denitrifying function. Previous paper (Part 1 and Part 2) stated mainly the mutual relation between denitrifying ability and recirculation ratio, redox potential level and reaction temperature in compound and actual wastewater. This paper attempts to discuss on the following items. 1. Influence of substrate in the influent such as C/N ratio to each nitrification and denitrification reaction progress. 2. Interaction between hydraulic loading of influent and each reaction progress. The following results were obtained in this experiment. 1. As for the C/N ratio value, more than about 2 would be required to keep effective denitrifying function. 2. From the result of hydraulic loading in influent, the desirable reaction time would be more than about 4 hours in nitrification process and about 6 hours in denitrification process at 25℃, recirculation ratio 4.

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In order to point out the characteristics of wettedness revealed under the constant average skin temperatures, three kinds of experiments were carried out using sitting-resting nude subjects. It is confirmed by the analyses of the experimental data that under the constant average skin temperature the wettedness does not remain constant, rather changeable. In other words, the maximum to the minimum wettedness values are observed corresponding to each average skin temperature. These characteristics of wettedness have great influences upon the locus of average skin temperature plotted on the psychrometric chart. Thus, the theoretical examinations were mathematically tried to clarify the influence of both human and environmental variables upon the average skin temperature line, which was based on the heat balance equation between the man and the environment. Each case of correlation between the wettedness and the evaporative heat loss from the human skin was examined in accordance with the classification table of the conditions to be expected. As the result, the most important factor drawn was that the correlation determines the form of the average skin temperature line.

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The purpose of this study is to clarify the energy savings by soil and lawn covered roofs for office buildings. Three kinds of experimental roofs were built in Kumamoto City, the thermal performance of which was measured by a microcomputer. A computer model for simulating the thermal performance of soil and lawn covered roofs was developed in which the microclimate in the leaf-air layer was considered. The preciseness of the model was made clear by comparing the simulation results with the measured ones. Using this model and a multiroom simulation program called PSSP, the air-conditioning loads of office buildings with four different kinds of roofs were calculated and the energy savings by soil and lawn covered roofs were analyzed quantitatively.

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This paper and next paper describe estimation and evaluation on utilization of the "unused heat energy" in the whole region of Nagoya. In particular, this paper deals with energy demands and potential of the "unused thermal energy". The energy demand was estimated in each mesh which has an area of about 500m×500m by multiplying building floor area by the unit energy demand assumed in the paper. Various maps about the energy demands in Nagoya were drawn according to the estimated results. The "unused thermal energy" implies heat source or sink which exists in urban region. Six categories of the energy are selected in the paper; water of Shonai River and Nakagawa Canal, water discharged out of the sewerage stations, waste heat out of the incineration plants, waste heat in the power distribution substations, waste heat out of the Shin-Nagoya Thermal Power Plant and waste heat in building cooling. Discussion is shown to utilize the "unused thermal energy" in the district heat supply system, and then energy potentials are estimated for the respective resources of "unused thermal energy". Finally the paper shows the areas which have potential to utilize "unused thermal energy" even somewhat.

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Deep seawater, compared with surface seawater, has more stable low water temperature characteristics throughout a year. It is available in vast amounts and can be considered to be renewable energy resource. We carried out space cooling experiments using the low water temperature characteristics of deep seawater at the research facilities for deep seawater. We evaluated the indoor thermal environment and the performance of a cooling apparatus. The main findings of the experiments are: (1) We were able to create a favorable indoor thermal environment by means of ceiling pipe cooling utilizing deep seawater of approximately 12℃ which is rather high for a design temperature (7℃) of a convectional air conditioning apparatus; (2) During daytime when the cooling load is high, the data obtained (from the experiments) which indicates an energy saving in the order of 40 percent compared with an electrical air conditioner: and (3) The heat transfer mechanism of the cooling apparatus used in the experiments (for the amount of approximate heat extraction rate) consisted of convectional elements (60%), radiative elements (20%), dehumidifying elements (10%), and heat loss elements (10%).

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Uncomfortable cooling due to the down draft of cooling air have sometimes occurred in conventional air cooling systems. This problem is particularly serious in hospital rooms since patients are staying still and thus they are more sensible and weak for cold draft. Full scale model experiments are carried out precisely in order to examine the performance of the panel cooling system in hospital room. Three types of cooling systems are examined, i.e. panel cooling only, cooling air supply only and combination of cooling air and cooling panel. Through analyzing these three cooling systems, the most appropriate cooling system that can avoid serious downdraft problem, is examined. The result of the panel cooling system shows that it is not effective to decrease the effect of the large heat load transferred from the outer wall to the occupied zone. Cooling jet system also does not perform well from the view point for reducing the effect of down draft near the bed. The combination of cooling jet and cooling panel is proved to be the most useful system from the view point of reducing down draft and minimizing the effect of large heat load from the window.

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The thermal environment in an air conditioned room with a cooling jet and a cooling panel on the ceiling is analyzed by means of numerical simulation which consists of the interactive heat transfer analysis between convection and radiation. The turbulence model used is the standard k-ε model. The convective heat transfer at wall is calculated using the convective heat transfer coefficient, α_c. The radiative heat transfer is calculated by means of Gebhart's absorption factor method. The results of the simulation are compared with those of the experiment. Followings are revealed by the analysis mentioned above: (1) The correspondence between the simulation and the experiment is faily good. (2) In the simple cooling jet system without cooling panel, a significant down draft into the occupied zone is observed. (3) However, the combination system of cooling jet and cooling panel is effective for reducing the down draft and decreasing the effect of large heat convection from the outer wall. (4) The value of convective heat transfer is almost the same with that of the radiative heat transfer at each wall.

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We determined how the room layout of an apartment and its natural cross ventilation affect overall indoor climatic comfort during the summer in Japan. To do this, we carried out three investigations at a corporate apartment complex: (1) a questionnaire on the degree of satisfaction concerning general dwelling environment, (2) a measurement of indoor climate with natural cross ventilation present, and (3) a survey on the use of air conditioning. We used such methodology because the way of living, as well as the occupants' psychological evaluation and the physical environment, are essential data for effectively evaluating the indoor climate with respect to room layout characteristics. The questionnaire clearly showed that natural cross ventilation, which influences indoor climate, affects on occupant's evaluation for having a comfortable dwelling environment. By comparing resultant indoor climate of three types of apartment floor plan, i.e., two side-corridor types and a staircase type, in terms of the standard new effective temperature (SET^*) and usage percentage of air conditioning, which were respectively determined from the indoor climate measurement and air conditioning survey, we found that the staircase type is more comfortable than the other types since it has the greatest velocity of indoor air flow. Regarding the way of living, the occupant interviews revealed that the restriction of natural cross ventilation at night due to privacy and security considerations made the dwelling environment extremely uncomfortable. Our results indicate that planning the thermal environment is an important factor affecting human standards of living.

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This report deals with experimental and numerical analyses carried out to investigate the discharge characteristics of a latent heat storage vessel by using encapsulated polyethylene glycol as the phase change material and water as the heat transfer medium. The heat transfer medium flows in the axial direction between cylindrical capsules arranged vertically in the vessel, and heat is exchanged between water and capsules. In the experiment, the transient outlet temperature was measured under several conditions controlled by varying the initial temperature within the vessel, the inlet temperature and mass flow rate of the heat transfer medium. In the numerical analysis, the outlet temperature was calculated by considering effects of natural convection within capsules and within the heat transfer medium during heat transfer. Experimental results were found to be in fair agreement with the results of numerical analyses.

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