It is sure the solar collector is the heat apparatus of a solar energy system. However, it is not the internal combustion engine but is the heat exchanger generally speaking. Therefore, the characteristics of the collector should be shown in heat transmission coefficient K, and sol-air temperature SAT as the primary site temperature of it. This paper explains the measuring methods and their results of SAT and K of both flat and glass tube vacuum type collectors. The strong point of this paper is to measure SAT by observing the temperature inside of the tube of empty collector, which is called as SAT meter. The method to determine every coefficient which want to presume SAT preliminary is described. Also, it is explained to use SAT meter in field is much better than to use η index of solar collector which has been world widely used nowadays, because η sometimes lead men misunderstanding, and is not convenient to control the system.

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This paper reports on a method to estimate the hourly global solar radiation using AMeDAS (Automated Meteorological Data Acquisition System) data. The AMeDAS is a weather data measuring system established by the Japan Meteorological Agency and can provide us with accurate, comprehensive data because it covers all of the Japanese islands with 838 measuring stations. One of the authors previously reported a method to estimate the hourly global solar radiation using mainly the hourly sunshine duration measured at the meteorological observatories. In chapter 3, the authors have expanded the same method to apply to AMeDAS and developed the equations for the estimation of hourly global solar radiation from the AMeDAS data. Generally the observed weather data contain such as regional differences and characteristics of instrument sensitivity, which influences the relation between global solar radiation and sunshine duration. In chapter 4, several stations which don't include peculiarity of data were selected according to the examination of the relation between monthly mean global solar radiation and monthly sunshine hours measured with AMeDAS, and coefficients of the equations for the estimation of hourly global solar radiation have been calculated from the data of these stations. In chapter 5, a practical procedure for estimation of hourly global solar radiation have been illustrated and estimated values from the formulae were compared with the measured values. The average values of the correlation coefficients and the standard errors over 20 cities are 0.951 and 0.282 [MJ/(m^2・h)], respectively.

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One of the significant problems in the present design method of natural ventilation is that the influence of turbulent wind on ventilation is taken no account of. The purpose of this study is to investigate the effect of the turbulent wind on ventilation rate of a room and finally to establish the design method of natural ventilation in which this effect is taken into account. In this paper, to examine the additional ventilation rate caused by turbulent wind, experiments to ventilate an enclosure with two openings, one of which faces to windward of artifitial wind and the other lies leeward, are carried out. Then to make the mechanism of ventilation caused by turbulence clear, the air flow through a windward opening is visualized by tabacco smoke. Consequently it turned out that the turbulence of wind causes the additional ventilation rate if the windward opening is over two times as large as the leeward opening and that in such cases the inflow and outflow through a windward opening occur at the same time.

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To keep air high cleanliness in a clean room, it is necessary to predict and control the distribution of airborne particles in it. There will be three methods for prediction; full-scale experiment, model experiment and numerical simulation. In this paper, the characteristics of diffusion process of airborne particles in a clean room is investigated by full-scale and model experiment. The experiment was conducted in consideration of some important properties of airborne particles, for example coagulation, deposition, sedimentation and so on. In spite of these properties, the diffusion process of airborne particles can be considered to be the same as that of passive contaminant, if the particles concentration is under the certain low level (10^<10> particles/m^3&cong;10^8 particles/ft^3) and the particle size is smaller than about 5μm, which are usually observed in practical clean rooms.

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The purpose of this study is to introduce the equations to estimate water demand in various buildings. This paper describes on elementary school and junior high school as the fifth installment of this series. The contents are as follows. We executed the investigations of water uses in elementary school and junior high school being in the major 11 cities of Japan in the same way as the previous papers. On these results, we clarified the properties of building and equipment, the conditions of water demand and the water conservation and the opinions of persons in charge of building maintenance for water uses. After that, we exhibited the approximate quantity about the estimate of building scale and water use equipment numbers, and we examined about the index of appliance numbers including users estimate, futhermore we analysed these factors using by the Quantity Theory Cluster III and clarified the relation between these item-categories.

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We have studied the operating performance of a large-scale metal hydride heat pump which utilizes a hydrogen compressor. Generally, the hydriding reaction of hydrogen storage alloy is exothermic, and causes a rise in the alloy's temperature. The dehydriding reaction is endothermic. We developed a new heat pump system that utilizes these exothermic and endothermic reactions. We adopted the 'shell and tube type' heat exchanger, which has middle fin tubes made of copper to enhance heat transfer. In this heat exchanger, there is a metal powder composed of calcium, nickel, misch metal and aluminum, and the heat is transferred through the metal powder and copper fin tubes to the water in the tubes. The hydrogen pressure in the shell is controlled by a hydrogen compressor. In this paper we discuss the relations between heat output, cycle time, hydrogen mass flow and temperature of hot water. We found that normal operation in combination with periodic no-load operation as shown in Fig. 4(b) is optimum, and it maximizes COP of the system. In addition, the design heat output (150000kcal/h) was achieved when COP equaled about 6. This heat output value is the highest in the world for a metal hydride heat pump system using a hydrogen compressor.

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When the fluid in a water tank is withdrawn from the drain pipe through a hole of its bottom, the appearance of vortex flow may be generally observed along the vertical line near its draining pipe. If certain conditions are satisfied, the suction of air into these pipes will occur along with developing the deformation of the shape on the free surface in reservior. As a results, this phenomena will introduce unfavorable effects such a vibration and noize associated with the two-phase fluid flow in addition to the extreme large frictional pressure drop along the draining pipe systems. In this paper, the steady vortex generated by the withdrawal from the plural exhaust pipes connecting with the bottom of reservoir are presented. Difference in the fundamental characteristics of vortex flow between the centric and eccentric portion of sink are examined through the measurement of their velocity distributions by means of hydrogen bubble method. It is shown experimentally that eccentric withdrawal added to centric one causes to the reduction of the strength of their vortex, and serves as the prevention from air suction into the draining pipes.

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This paper is the first report of our series of studies on the method to determine a velocity distribution from video images of visualized flow through image processing and numerical calculations. In the series of studies, we intend to develop a flow measuring system of the following type: (1) Simple, cost-effective system. 1) Images are treated only as electric signals, not transformed to photographs or films. 2) The system is constructed using only equipment already commonly available. (2) System available also for low-velocity air-flow measurement. In this paper, the methods of finding particle couples in consecutive video frames (necessary to the estimation of velocity distribution from the images visualized by particulate tracers) are compared by computer simulation. The methods compared are the following three: (I) In any two consecutive frames, particles in the closest spatial proximity are considered to be the same. (II) In any two consecutive frames, particles having similar brightness pattern in their neighborhood are considered to be the same. Namely, it is assumed that the correlation factor between two brightness distributions surrounding the particle images in both frames is highest when they are the same. (III) In any two consecutive frames, a particle pair is arbitrarily selected when they are in close proximity, and the line connecting the two particles is extended for a length equaling the distance between the two particles. A particle in the 3rd frame is looked for in the neighborhood of the line end. A particle in the 4th frame is also looked for in the same manner, and if both are found out, then these four particles are considered to be the same. A Poiseuille flow between two parallel plates or a Karman vortex street is assumed, and the tracer supplying, the floating down of tracer particles, the sampling of visualized images and the reducing to binary pictures are simulated in the computer. Same particles in consecutive images are identified by method (I), (II) or (III), using the centroid and area data of tracer particles, and the correct identification percentage and CPU time are estimated. The results obtained were summarized as follows: 1) For the region where maximum displacement of particles between two frames is less than 0.5×(average space among particles in each frame), method (I) is preferable. 2) For the region where maximum displacement of particles between two frames is less than 0.1×(dimension of the frame), method (II) or (III) is preferable. The choice of the two depends on the system's speed of image processing and logical operations. 3) Beyond the above mentioned range, only method (III) is available. 4) When particle diameter distribution spreads widely, the available range of each method increases.

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The questionnaire inquiry on building service systems and indoor environment of office buildings was conducted from 1983 through 1984 in four cities, Fukuoka, Kumamoto, Kagoshima and Oita in Kyushu District. Similar surveys have ever been carried out, but almost in metropolises such as Tokyo, Osaka and Nagoya. There are many differences between cities in climate, customs, economy, social activity, etc., which influence energy consumption, especially for air-conditioning. Therefore it is of much importance to analyze the characteristics of local cities by conducting surveys so as to summarize the general aspects over all the country. First, this paper describes general aspects of consumption by comparing electricity, city gas, petroleum and total energy between public building, ownership building and tennant building and with the surveys conducted in other districts. Second, using annual variation of consumption of each energy for each building, all buildings were classified into eight types of air-conditioning, according to combination of energy used for cooling and heating, on the basis of which the authors attempted to estimate energy consumptions for cooling, heating and the miscellaneous. Finally, multi-regression analysis was applied to the energy consumptions estimated above.

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The synthetic survey on building service system and indoor environment of office buildings was conducted form 1983 through 1984 in four cities, Fukuoka, Kumamoto, Kagoshima and Oita in Kyushu district. At the survey, questionaire items about water demand were added. In this paper, characteristics of water demand of office buildings in four cities was investigated, and was compared with the results of similar survey at the five areas other than Kyushu district. The summary of this investigation results is as follows. 1) The yearly water demand of office buildings in Fukuoka city was least of them in four cities. In regard to building description, water demand of ownership buildings and tennant buildings was more than it of public buildings in Kumamoto city. 2) When it was compared with the results of similar in five areas, Tokyo, Kanagawa, Osaka, Aichi, Hokkaido, expect for Kyushu district, water demand of office buildings in Fukuoka city was least of them in other areas, and subsequently it in Aichi and Oita city was little. 3) Multi regression analysis was applied to the water demand, and the regional differences and the classification of the office buildings were selected for the explanatory variables using the stepwise method.

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This paper presents a numerical prediction method for unsteady state thermal environments in a heated room, including calculations of the distribution of thermal radiation and of comfort indices, and also presents the results of the application of this method to a periodically heated room with electric floor panel heating (EFPH), hot water floor panel heating (HWFPH) or forced convective heating (FCH) to illustrate the characteristics of the heating systems. For steady state and transient conditions, a prediction method and the calculated results of the heating systems were already shown by the authors in the previous papers (1), (2). In this paper, periodic heating hours are assumed (i.e. 5:00〜8:00, 11:00〜13:00 and 15:00〜21:00), and a calculation method for HWFPH is developed based on a numerical calculation of two dimensional thermal conduction around a hot water pipe as shown in Fig. 2. As in the previous papers, the calculations are conducted on a room model shown in Fig. 1. The air temperature and air velocity are assumed to be uniform, and appropriate values are employed as known values for the air velocity and convective heat transfer coefficients. For EFPH, a constant heat flux is assumed for a heat source plane. For HWFPH, a constant temperature and a constant flow rate are assumed for hot water. For FCH, a constant heat supply is assumed for room air. Using the backward implicit finite difference scheme, the time dependent variables of thermal environment are calculated, and they reached periodically steady state after 20 days. The results shown in Fig. 5〜12 illustrate well the characteristics of these heating systems quantitatively. They are, however, dependent on the various conditions assumed, the characteristics of heating systems can be shown more clearly by systematic analysis for the various conditions with the prediction method developed in this paper.

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This paper deals with the characteristics of convective diffusions of a leakage, such as inflammable or harmful gas, in rectangular cavities which are aside a main flow way and ventilated from a single side. The flow visualizations for various aspect-ratios of the rectangular cavity were carried out with the water flow channel taking the difference of the density between the leakage and the main flow into consideration. The leakage was flowed out from the center on the end surface of the cavities at the velocity 0.15〜0.16U_C (U_C: main flow velocity) and flow rate about 2×10^<-5>Q (Q: main flow rate). The Froude number Fr, which was based on the width of the way, the velocity of the main flow and the difference of the density between the two fluids, was ranged from 1.1 to 3.4. The aspect ratio of the cavity D/W (W: cavity width, D: cavity depth) was widely changed in a ranged D/W≒0.1-8. The summary of the experiments of the flow visualization is as follows: 1) For D/W≒1, the ventilation flow from the main way was circulated strongly within the whole of the cavity. The leakage was also convective diffused by the recirculated flow. We thought that the problem about the ventilation in the cavity of this aspect ratio was comparably less serious than that of the other aspect ratios. 2) In a ranged 0.1<D/W<0.7, the ventilation flow was circulated within the down stream region of the cavity, while the leakage was convective diffused within the upper stream region by weak secondary recirculation flow. So the concentration of the leak matter within the upper stream region was comparably high. 3) For D/W&gsim;2, the leak matter formed layer on the floor within the interior region of the cavity without the inlet region in which the ventilation flow was circulated. For those cavities, a local ventilation equipment will be needed to disturbed forming the layer near the end surface.

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This paper describes the properties of convective diffusion and the layering of a leak gas in a rectangular cavity (depth/width=D/W=3) aside a main airway and ventilated from a single side, such as a underground cavity. Experiments were carried out with a small-scale model leaking pure methane gas from the center at the end surface of the cavity. The average methane concentration C_<xm> over x-direction (flow direction of the main air way) in the cavity was measured by the adsorption of infrared rays (generated by He-Ne gas laser with 3.39μm wave length) through the cavity. The measurements were conducted in the ranged Froude number Fr=3〜40, the injection rate of leak gas q_i/Q_0=68×10^<-6>〜570×10^<-6> and the injection velocity v_i/U_C=0.038〜0.65. The distributions of C_<xm> at the middle level (z/H=0.5) in the cavity were compared with ones at the upper level (z/H=0.875). While C_<xm> at the middle level was higher than that of upper level of the interior region (y/D&gsim;0.5) in the high Froud number region Fr&gsim;20, the relation between the two was reversed in the low Froud number region Fr&lsim;8. As a result, critical Froude number Fr_C, under which the gas concentration at the upper level in the interior region of the cavity begins to increase by forming the gas layer near the ceilling of the cavity, ranges between 8 and 20.

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