From among artificial waste heat generated in urban areas, our group has made the calculation program of the waste heat character to clarify the actual amount of it, focusing on the waste heat from buildings. Based on the results of the calculation, the amount of waste heat from buildings including the air-conditioning system was determined quantitatively. And difference of the waste heat of time character between supplied energy and total amount of waste heat from buildings was clarified. Moreover, we has built up five kinds of heat source equipment model and calculated similarly. From the results, it has been clarified that the waste heat character of each system is greatly different in summer term depending upon the difference of air-conditioning systems.

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This paper describes an experimental study of the estimating method of metabolic heat change of during working hours that fluctuates with the lapse of time. Office work in a college office, a construction company and gymnastic facilities was videotaped. From these tapes, the office work in each site was examined and analyzed. The results show that: 1) The total of 36 different body actions were observed in the office work in the afore-mentioned sites, and 2) each of the various body actions were of short time duration. Then, empirical equations of transient metabolic heat were deduced from the beginning of the movement to the end. An estimating method was proposed for the metabolic heat of the office personnel, considering the situation of successive movements in a short time, using the following factors: The metabolic heat of each movement, empirical equations and time duration of movements. In addition, experimented values were compared with theoretically calculated values of a work model. The result shows that the mean value of metabolic heat, obtained by a time weighting method, would potentiality yield significant error.

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This paper describes an experimental study on a removal method of aerosol particles in air by condensing the preliminarily heated and humidified air. In the experiment, air including aerosol particles is circulated by a fan in a closed clean room system which consists of a closed vessel, a humidifier, two condensers and an after-heater, and the number concentration of aerosol particles at the inlet of the closed vessel and the relative humidity and temperature in the system are measured for several conditions of humidification and condensation. It is clarified that the removal rate of aerosol particles in air increases when the mass flow rate of the condensate increases by means of enlarging the temperature difference between the heating water in the humidifier and the cooling water in the condensers. It is also shown that this method is more effective when the temperature level in the humidifier is risen. The aerosol particle removal mechanism of this method may be related to the generation of mist using aerosol particles as nuclei, the inertia trapping, the suction effect of condensation and so on.

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Energy consumption and CO_2 emission for the construction and the operation of an environment-oriented office building were calculated and compared with an existing reference office building. Environment-oriented means are use of recycled materials such as electric furnace steel and concrete block, providing balcony for easy contact with nature and atrium for day-light utilization and office amenity. Solar battery, fossil battery and task/ambient lighting system are provided for energy saving. The structure of two buildings have 6 stories with 1 basement floor and the floor area is about 11000m^2, but the building area of environment-oriented office building with atrium is 10% larger than the reference office building. Energy consumption and CO_2 emission for construction are calculated with input/output analysis using the table in 1990. The effective means for construction are use of electric furnace steel, which final production energy is 57.3% of convert furnace steel. Task/ambient lighting system is also effective for operating energy consumption, which electricity load is 57.5% of general ceiling-lighting system. Though the investment of the environment-oriented office building increases 2.9% compared with the reference office building, energy for construction decreases 12.5%, and CO_2 emission, 16.6%. The energy for operation decreases 26.1% and CO_2 emission, 19.8%. Payback period which is a value of increased investment divided by decreased annual operating cost, counts for 5.9 years, so the environment-oriented office building keeps within the bounds of possibility.

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Most of the AMeDAS (Automated Meteorological Data Acquisition System) stations measure temperature, precipitation amount, sunshine duration, wind direction and velocity. However, no measurement on vapor pressure is made, although it is one of the indispensable meteorological elements for the estimation of air-conditioning load. This paper reports the investigation of the possible methods for appending hourly vapor pressure to AMeDAS data. Mainly two methods have been proposed and examined. A brief explanation on these two methods and the accuracy of the appended vapor pressure are as follows; 1) Method-1: This method predicts hourly vapor pressure at an arbitrary AMeDAS station by modifying the temperature, measured at the same station. When the annual and daily periodic components are extracted from the time series of hourly temperature for a year, the variation of the residual component becomes similar to that of the time series of hourly vapor pressure of the same year, provided that the annual periodic component is extracted. Therefore, the time series of hourly vapor pressure for a year can be predicted, by combining the residual component of the temperature and estimated annual periodic component of the vapor pressure. The estimation of errors by this method is around 2.5hPa. 2) Method-2: This method appends the hourly vapor pressure to an arbitrary AMeDAS station by interpolating the hourly vapor pressure observed at the surrounding weather stations. Several interpolation methods are examined and it clarifies that the weighted average of the observations by the reciprocal of distances between AMeDAS and the weather stations, gives a reliable prediction for the vapor pressure at the AMeDAS station. However, adjustments based on the altitude and temperature difference between the AMeDAS and weather stations are required when the temperature and the altitude differences exceed to a certain degree. The estimation of errors by this method is around 1.2hPa.

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Fluctuation characteristics of wastewater discharged from households were evaluated, and a method for analyzing the fluctuation was proposed. In addition, the analyzed results were confirmed using a structural modified system. Intensive discharge of wastewater was concentrated in short periods, especially, when washing clothes, washing dishes, and cleaning the bath tub. Fluctuation characteristics of wastewater discharge were analyzed by the queue technique to solve batch arrival problems. This method allowed simple estimation of the capacity of the temporary storage chamber, and the flow equalization ratio of 1.5〜2.0. By installing the chamber, a fluctuation of wastewater discharge could be reduced to 1/4〜1/7.

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In this paper a modeling has been applied to an air-conditioning system by taking the multivariable AR (autoregressive) model into account by using the observed data and the simple 3 input/2 output model for the implementation of a new practical optimal control has been constructed. The LQG (Linear Quadratic Gaussian) optimal control with feedforward compensation has been applied to control process variables such as indoor-temperature and indoor-humidity. The experiments on a commercial sized test plant suggest that the LQG control with feedforward compensation is extremely good for the air-conditioning system and enables us to improve a tracking property for a reference input in the transient state, and also to guarantee the global stability in the steady state.

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Rapid increase of global population, extension of economic activities, and technological innovations bring about environmental disruption on an unprecedented global scale, and are breeding the problems which nobody have anticipated. Authors carried out the social surveys on three areas in Nagoya and on three areas in Tokyo. This paper aims to clarify the consciousness of inhabitants on energy conservation, resource preservation on their daily lives and environmental issues on a global scale. Authors obtained the results as follows: Over 80% people were interested in global warming effects. And it were about 60% people that understood details of them. 2) With respects to global environmental issues, a little people gave "negative" answers, simultaneously a little people gave "positive" ones, and the majority gave "slightly positive" ones. 3) People who thought that we ought to buy the secondary material products even at a higher prize were never small part of subjects. 4) As a results of analyzing the data to global warming effects from two-waved panels, the number of subjects who switched answers was not small, and the reliability were seemed to be low. 5) There were some questions that bear relations to subjects' ages and there were some questions that bear relations to subjects' school careers. 6) The questions related to subjects' ages involved in "saving" or "concern". The cause might be judged to be not "aging" but "cohort". If so, subjects' answers to these questions might shift negative-ward in the future. 7) The questions related to subjects' school career was ones requiring of "expert Knowledge" or "profound comprehension". It will be possible to improve their consciousness by intensifying environment education and furnishing appropriate information.

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These control method decisions are important to design the secondary pump system. The purpose of this study is to find the optimum control method in the secondary pump system. This report explains the experimental method in an adjustable building, and shows the results tested by using six control categories and two control methods. Also we analyse many data about the energy conservation and the operational characteristics. From the experimental results, it's important to control the middle・lower flow, and the best control is the two inverter control/the multiple units control. In the other side, the best energy conservation is the one standard flow/the one inverter control・multiple units control.

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Volcanic ash erupted from Sakurajima Volcano variously influences on air-conditioning systems. Especially, it requires considerable maintenance for air filters. Therefore to develop the air filters suitable to eliminating volcanic ash and lowering the maintenance is very important for the districts around Sakurajima. In this paper, two kinds of trial air filters are produced and the performances of them are experimentally examined. First, a trial filter, designed on the theory of inertial dust collection, is produced. The filter is intended to be set at the upstream side of the finer filters to decrease their load. The ash collecting part is formed using curved eliminators with or without grooves set parallel to the direction of the ash-containing air flow. Ash collection coefficients are examined using volcanic ash collected from several places around Sakurajima. The overall ash collection coefficients are between 70% to 90% for eliminators with grooves, 65% to 85% for eliminators without grooves, when the air velocity is less than 4m/s. The partial ash collection coefficients, corresponding to the ash diameter regions 0〜75μm, 75〜125μm, 125〜250μm, 250〜500μm are 22%, 75%, 98% and 100%, respectively, when the air velocity is 3m/s. These values decrease to 9%, 40%, 89%, and 99%, respectively, when the air velocity is 4m/s. It is verified that the overall ash collection coefficients synthesized from the partial collection coefficients are similar to those by measurements. Next, the efficiency of a wet type ash filter is examined. Water circulating system together with an water spraying nozzle is attached at the upstream side. The ash collection coefficient by this filter is more than 97%. However, as wet ash gradually sticks on the eliminator with water spraying, which will eventually require the maintenance, it can only be recommended to be used in the restricted area where the influence of ash is serious.

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In this paper, we will propose numerical prediction method for evaluating surface to surface radiation which can be applied for a three dimensional arbitrary complicated geometry over ten thousands divided surface elements in reasonable computation time and storage. As for fast calculation of view factors between surface elements, we propose next two methods; (1) searching visibility of many surface elements successively instead of each one as precalculation, (2) setting optimize number of integrating point on surface elements by non-dimensional parameter related positions and shapes of two surface elements automatically as numerical integration. View factors calculated in this process are also well-stored to reduce computational storage. As for stable and fast calculation of heat balance equations associated with thermal radiation, convection, solar radiation absorbed and wall conduction in each wall and heat balance equation in whole space including the effect of air-conditioning and ventilation, iterative method such as successive under relaxation is adopted, which is naturally considered multiple reflection of radiation. We applied this method to model room including obstructed surfaces with thermal radiation panel which has normal glass or low-emissive pair glass as windows. Surface temperature distribution, heat balance on each wall, vector radiant temperature and mean radiant temperature for thermal comfort indices are predicted to demonstrate the performance of this method in each case. The validity is confirmed by the results compared with other prediction method.

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The flow pattern of a miter-tee with the branching angle θ_m of 90° and with chamfering at the lateral entrance was studied for laminar flow. The area ratio m was chosen to be equal to 1.0, 1.5 and 2.0 and the magnitude of dimensionless chamfering C was chosen to be equal to 1.0 for each m. Moreover, C was chosen to be equal to 0.5 only for m of 1.0. The Reynolds number Re_<1h> was taken to be less than or equal to 200. The ratio of lateral discharge to total discharge Q_3^*/Q_1^* was changed from 0.0 to 1.0 at 0.1 intervals. The obtained results are compared with the cases with sharp edges and rounding at the lateral entrance. The conclusions can be summarized as follows: 1) The Navier-Stokes equations were solved numerically by the finite difference relaxation method when Re_<1h> covering the range between 1 and 200. The influence of such parameter as m, C, Re_<1h> and Q_3^*/Q_1^* on the flow separation caused from the lateral entrance and the stagnation point was investigated. The effect of the flow dividing in the lateral conduit is larger than that in the main conduit. Its degree in the lateral conduit grows when the separation occurs. Generally, the separation occurs at the large value of Re_<1h> when Q_3^*/Q_1^* is 0.5 and Re_<1h> varies and at the small value of Q_3^*/Q_1^* when Re_<1h> is 70 and Q_3^*/Q_1^* varies. The degree of the separation caused from the lateral entrance with chamfering is larger than that with rounding or the sharp edges there. The former is larger than the latter when Re_<1h> is 70 and Q_3^*/Q_1^* is small. Although the separation occurs from the lateral entrance with sharp edges, no separation occurs from the lateral entrance with chamfering and rounding when Re_<1h> is 70 and Q_3^*/Q_1^* is 1.0 or in the neighborhood of 1.0. The mechanism of the flow separation is discussed physically. Besides, 2) the influence of Re_<1h>, Q_3^*/Q_1^*, m and C on the stagnation point is studied. The stagnation point is located on the lateral wall of the middle point of the main conduit independent of Re_<1h>, m and C when Q_3^*/Q_1^* is 0.5. But it varies with the values of m and C when Re_<1h> is 70 and Q_3^*/Q_1^* is changed. Its degree is larger than that with rounding but smaller than that with tha sharp edges at the lateral entrance. 3) The flow field in the real pipe junction with rectangular cross section was studied experimentally by the flow visualization technique when Re_<1h> covering the range between 5 and 200. The flow is two-dimensional at Re_<1h>≦40 but it is three-dimensional with secondary flow at Re_<1h>≧70. The flow adjacent to the centerline plane is always observed to be two-dimensional. The influence of m, C, Re_<1h> and Q_3^*/Q_1^* on the flow separation caused in the lateral conduit and on the stagnation point was investigated. 4) The results obtained by the numerical analyses and experiments coincide fairly well. Both results coincide quantitatively well when Re_<1h> is small or when Re_<1h> is large but Q_3^*/Q_1^* is small.

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