This report shows our investigation of energy consumption on the existing office buildings, and proposes fundamental data and method of diagnosing energy conservation. Each building has its own original energy consumption but has something in common depending on use of the building. In this report, we formalize the result of multiple regression analysis about relation between energy consumption of HVAC & Refrigeration and outdoor air-condition as simplified inferential formula. To a certain degree, we can regard this formula as the fundamental data through the preliminary study of energy management in the existing buildings for the purpose of energy conservation (These data were measured from 1981 to 1985. Total floor area of these buildings counts for 1700〜39000m^2. The average is 7700m^2).

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To evaluate surface contamination of materials and products in clean rooms due to particulate matter suspending in air, it is necessary to predict deposition rates of aerosol particles. Deposition of particles, particularly those larger than 1μm, is often a problem in various kinds of industries, such as pharmaceutical, food, and biotechnological industries. In this paper, deposition of particles onto a horizontal wall in a clean room is studied for particles with diameter between 0.5 and 3μm. In the experiment, a laminar circular jet of aerosol, the average velocity of which is equal to that of air in the room, is impinged onto metal plates. To investigate effect of electrostatic forces on the deposition, positively or negatively charged plates and a grounded plate are used as the walls onto which the deposition occurs. Deposition velocities of monodisperse aerosol particles are obtained by observations of particles deposited on the wall surface by an optical microscope. Amounts of electrical charge on individual particles are also measured to obtain charge distribution of the aerosol particles. The measured deposition velocities are found to show a good agreement with those calculated from coulombic and gravitational forces acting on the particles. It is also suggested in this work that both the particle charge and the electric field in the vicinity of the wall are indispensable in prediction of particle deposition.

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The effect of a tube bank setup in a symmetrical and two-dimensional conduit with an abrupt expansion on a flow pattern is studied by experiments and computations. The experiment shows that without using tube banks the flow pattern is asymmetric, but when the tube bank is equipped with the conduit, a symmetric flow pattern occurs. A hypothesis is theoretically considered for the effect of the tube bank, and the vorticity transport equation modified by the hypothesis, together with equations for turbulent quantities in accordance with the k-ε model are solved numerically. Computational results show that the symmetrical pattern in the conduit with the bank occurs. The frequencies with which vortices are shed behind each tube in a tube bank, where air flows nonuniformly, are also measured.

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Monthly statistical weather data from stations around the world are compiled for periodical base heat load calculations. The source data are the publications by Meteorological Office (D1), the magnetic tape compiled by the Japan Meteorological Agency (D2), the literature on the world solar radiation distribution by the solar energy laboratory at the University of Wisconsin (D3), BIN solar radiation data by ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) (D4), and the solar radiation observations at Japan Weather Observatories (D5). The weather elements required for ordinary heat load calculation are air temperature, humidity, solar radiation, wind direction, wind velocity and cloud cover. Among these weather elements, D1 and D2 include air temperature and relative humidity, and D2 contains additional three elements; i.e., wind direction, wind velocity and cloud cover. Since both the stations in D1 and D2 lack in solar radiation data, they are supple-mented from those at the nearest stations in D3, D4 or D5. Wind direction, wind velocity and cloud cover for D1 stations are cited from those at the nearest stations in D2. As the result, the monthly weather data for heat load calculation are compiled at about 2400 and 2000 stations listed in D1 and D2, respectively. Excluding the overlapping stations in D1 and D2, more than 3700 stations all over the world are obtained. These data are recorded as the random files of a personal-computer. The approximate memory sizes of both D1 and D2 files are 1.1MB (mega-byte). The procedure for the estimation of daily variations of weather elements, and the method of the heat load calculation using personal-computer will be discussed in the following report.

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This paper describes an investigation and analysis on building facilities by remote monitoring system from the operational reliability point of view. This investigation was conducted from 1986 through 1988. In this paper, firstly the outline of this system, survey and analysis data are described. Secondly conditions of giving alarms are presented under the following classifications. 1) Application of building 2) Scale of building 3) Month, date and time 4) Cause and kind of facility We investigated the statistical characteristics and tendencies by many-sided analysis. The summary of the tendencies and characteristics is shown below. 1) Concerning the application, it occures frequently an culture facilities. 2) Concerning the scale, it occures frequently in small/medium size buildings. 3) Concerning the month, date and time, it occures frequently at the starting of air conditioning due to load fluctuation. 4) Concerning the cause and the kind of facility, it occures frequently at the malfunction of heat source systems.

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Systematic experiments were conducted in order to obtain data for the proper design values of bath and shower equipments. The experiments were conducted mainly to determine the comfortable range of hot water temperature and flow rate based on the subjects' votes and were composed of three parts. In the first part, single use of shower was assumed and the experiments were conducted in case of the fixed overhead spray head. The second part was intended for the regular bathing, and the proper condition for the handheld shower during body washing and the optimum temperature of the bathtub before and after taking shower were considered. The last part was aiming at evaluating reheating systems which have been commercially available in the recent automatic bath heating systems, anb three typical systems, that is, the forced circulation system, the semi-forced circulating system and the high temperature supply system, were chosen and the comfortable conditions in each cases were tested. According to the shower experiments, the hot water temperature of 40℃ at the flow rate of 12l/min within the fluctuation ranging ±1.5℃ for the temperature and ±1.5l/min for the flow rate appeared recommendable for the most popular spray head type, although the flow rate value may be reduced to some extent if soaking in the bath before or after taking shower is assumed. The experiments concerning the reheating systems suggested that the current reheating systems are not completely sufficiant and should be improved because reheating during taking a bath can be a source of discomfort.

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The reevaporation phenomena at cooler fin surfaces during compressor stopping have been utterly neglected so far in designing industrial and residential air-conditioning systems. This paper demonstrates experimentally as well as numerically that indoor humidity can be controlled more precisely by taking account of the effect. In the previous paper, a numerical model equation was developed for predicting indoor humidity variation, and it was clarified that the calculated results were compared well with the experimental ones in a commercial refrigerator. In the present paper, the results of experiments are described for residential air conditioning, and the calculated values by the developed equation again coincided with the experimental ones. Based on this results, a new design method using the equation was presented for selecting proper capacity of dehumidifiers. To elucidate the effect of undesirable reevaporation, measurement of the quantity of reevaporation of a residential cooler was carried out. From the results, the relations between the temporary rise of humidity and the reevaporation were clarified, then some methods to restrict the effect were proposed.

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The object of the present study is to search sound sources on rotating blade surfaces of propeller fan by measuring distribution of pressure fluctuating part. Such experimental studies have seldom been found. The experiments were carried out on two new types of fans applicable to air conditioning system. One of them is an aerofoil type and the other is a thin plate type. The causes of noise are discussed using the experimental results of frequency spectrum of sound and of cross correlation between pressure fluctuating part on rotating fan blade and sound pressure at a point downstream of the fan. The following conclusions are obtained: 1) Noise due to blade vibration is negligibly low because of use of good damping materials. 2) Source of rotation sound is found at the leading edge part and the pressure fluctuating part with broad band higher spectrums is observed at the tip side of the trailing edge part. 3) Noise downstream of a fan is affected by time derivative of the pressure fluctuating part on rotating blade surfaces.

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In this paper, we investigate a countermeasure of zinc oxide fumes exhaling from the metal melting shop of a casting plant. It is most effective to establish a local exhaust system by using a canopy hood for a plume containing a lot of fumes from a heat source, depending on the working condition, however, there are some difficult cases to cover a hood on a plume source. In such a case, though a push-pull ventilation would be effective to exhaust fumes, there are few design data on a three dimensional push-pull flows with mighty buoyancy. Therefore, the dimensions of push-pull system are decided after taking working conditions into consideration, and then, the push-pull flows are simmulated numerically in order to obtain appropriate push and pull velocities to exhaust plume containing zinc oxide fumes. Numerical calculations are performed by using SIMPLE method, provided that air density is handled as a variable. A real size of push-pull system is made based on the results of numerical calculations, and experiments are performed at the actual melting shop to confirm the effectiveness of the push-pull ventilation. As the results, it becomes clear that the plume can be kept sufficiently under contorol by the push-pull velocities obtained from numerical solutions and the actual plume flows agree well with the numerical results. From the above facts, we may conclude that the numerical method may be an effective measure to design a push-pull ventilation system.

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This paper deals with the characteristics of heat and moisture transfer in forced-draft packed towers, such as the water cooling tower, the heating tower using aqueous solutions of ethylene glycol, and the dehumidifier using aqueous solutions of lithium chloride. First, the methods of calculations are presented for both counterflow and crossflow towers, which take into account heat- and mass-transfer coefficients in gas phase and also physical properties, such as the enthalpy and the vapor pressure of liquid. Next, lots of existing experimental data are analyzed by the methods. Judging from the results, the approximate relation proposed by Lewis is applicable to the above air-aqueous solution systems as well as the air-water system. Therefore, it will be a proper method of approach for these towers to consider the overall volumetric enthalpy-transfer coefficient, Ka. Moreover, the variation of concentration in a non-freezing solution circulating through a heating-tower system is measured to compare with estimated one from a value of Ka.

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