Hitherto few studies have been presented about air-outlet diffusers using swirl flows. The object of this study is to develope a air-outlet diffuser utilizing swirling air flows. The outline of the diffuser offered to experiments is as follows. Two cylinders are combined concentrically coinsiding with one axis to another. The primary air is blown into the diffuser through a inlet attached to the outer cylinder tangentially and flow spirally downward the annular channel formed by them. Secondary air is induced through the inner cylinder and mixed with primary air inside the diffuser. The mixed air is discharged from it as a swirling round jet. In this paper some geometrical factors governing the characteristics of induction were detected and their proper values were determined experimentally. As a result, following facts were clarified. (1) The ratio of the outer cylinder length to its diameter should be larger than 2.0. (2) The performances of induction are governed chiefly by the following three factors; 1) The ratio of cross-sectional area of primary air inlet to the cross-sectional area of outer cylinder. 2) The ratio of the cross-sectional area of the annular channel to the cross-sectional area of outer cylinder. 3) The length of the annular channel.

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On-site energy system is a system which generates power and heat on the spot and is considered as one of the alternatives of energy saving system. Due to the fact that many complicated items existing in such systems, this research has been carried out in an attempt to show a new dealing of design related to an on-site energy system in a systematic method. Through basic analysis of energy flow in the on-site energy system and conventional system as well, it was found out that 12 kinds of energy usage are of special characteristics in consumption, whereas three of them are to be considered as basic ones and also as independent parameters, i.e. common demand of electricity, energy demand for cooling as well as well as energy demand for heating and hot water supply. By knowing those three parameters, quantity of input energy requirements can be determined. Consequently, optimal options of the appropriate energy system type for a building for instance, could be deduced out of the proposed method. Survey of energy consumptions in 8 office-buildings in Tokyo has been made. Data were obtained on electric power consumption, flow of high-tension electricity for electric driven refrigerator and oil consumption of boiler on the bases of time-interval per hour, day, month and year. By statistical analysis of the data, characteristics of the above mentioned three basic kinds of energy usage were obtained. They are average and change of consumption and standard deviation. According to those characteristics and by considering size and efficiency of the equipments, energy requirements in buildings for three basic kinds of energy usage were modelled, in which the model was considered to be composed of standard energy requirements and energy requirements' change and fluctuation per month as well as per hour. As a result, standard energy requirements were set to have the value of 27.3W・h/m^2・h of common demand of electricity, 56.7kcal/m^2・h of energy demand for cooling and 26.0kcal/m^2・h of energy demand for heating and hot water supply. For monthly and hourly considerations, change and fluctuation were introduced by means of expected average values and standard deviations. In the case of monthly approach, expected average values and standard deviations were set as ratios of daytime requiremets for one weekday to standard energy requirements. However, in the second case, namely the approach per hour, two ratios were set as follows: (a) energy requirements per hour to monthly expected average values and (b) standard deviations per hour to the already mentioned standard energy requirements. Here differences among weekdays, Saturdays as well as Sundays and holidays have been taken into consideration. The knowledge obtained about energy requirements in buildings would be applied to a system simulation model. Details over that model will be presented in consequent papers. The final result which should be achieved within the frame-work of this research, is crystallized by the ability to evaluate and design an on-site energy system.

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The dividing flow mechanisms in pipe junctions were studied in a systematic way. First, the energy loss due to flow dividing was measured and its mechanism was considered. Next, the separation point in the main conduit of a junction with an arbitrary branching angle and areal ratio was analyzed theoretically for laminar and turbulent flow and was evaluated for the branching angles of 45°, 90° and 135°.

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Much literature is known related to a single pipe junction and a manifold for a long time. Nevertheless. as cross-sectional area ratios of branch to main pipe and branch spacings are kept constant in a large majority of much literature, the relations between the loss coefficients and those factors are not clarified when the values of those factors are varied respectively. However, in order to design the uniform lateral outflow from a perforated conduit or a slot, it is necessary to consider the area ratios and branch spacings and so forth which are supposed to be important for the design. Therefore, as the first step the following is tried to make the fundamental data on the uniform outflow from a perforated conduit or a slot; that is, the characteristics of the outflow from an orifice is analyzed by using the momentum theorem, and some factors are adopted. According to the results of experiments, it becomes clear that the analyzed values coincide comparatively well with the experimental ones in the case of a single perforated pipe.

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Two cooling systems have been adopted in order to manage the heated water discharged from thermal power plants and various industrial factories. They are once through cooling system and recycling cooling system which uses cooling towers or cooling ponds. There are two cases in the once through cooling system; one is when the heated water is discharged into the surface of receiving bodies of water, the other is when the heated water is discharged from submerged diffusers. In the former surface buoyant jets are formed, and in the latter the submerged buoyant jets or plumes are. A lot of theoretical and experimental studies have been performed in order to predict the behavior of these jets or plumes. These studies are very important in order to minimize the undesirable influence of thermal effluents on aquatic life. In the first to third report of this study, was investigated the influence of some main factors, such as velocity ratio, densimetric Froude number and geometrical boundary conditions, on the behavior of horizontal surface buoyant jets. The purpose of this paper is to clarify experimentally the influence of velocity ratio and densimetric Froude number on the maximum cross-sectional area A^<**>_<max> and the Volume V^* within isoconcentration contour, when the heated water is discharged from bottom into a cross flow in a rectangular open channel. Furthermore, the approximate equations are discussed which represent the relations between V^* and temperature, and between maximum temperature T^*_<max> at the cross section of a channel and the distance downstream from the slot. These equations were derived by making a few corrections for the analytical solutions for the two dimensional turbulent diffusion problem when the heat was released into the uniform cross flow from the line heat source at the bottom of the receiving water. The influence of velocity ratio on A^<**>_<max> and V^* was investigated under four different Froude numbers, and the influence of densimetric Froude number was investigated under four different velocity ratios. Froude number, Reynolds number and the average velocity of a open channel are constant throughout all experiments. Some main results are as follows; 1) Mixing and turbulent diffusion is very large in the case of submerged buoyant jets in comparison with the case of surface buoyant jets. 2) A^<**>_<max> and V^* increase with velocity ratio, and the rate of increment is larger in low temperature range than in high temperature range. 3) The influence of densimetric Froude number on A^<**>_<max> is small, but V^* increases with densimetric Froude number. 4) The experimental results for V^* and T^<**>_<max> are well described by the approximate equations which are derived by making a few corrections for the analytical solutions for the two dimensional turbulent diffusion problem when the heat is released from the line heat source.

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An air conditioning system design or evaluation program has equipment data. Data in catalogs is seldom available in a form suitable for economic storage in computer. The equipment data is reduced to simple functions using polynomial curve fitting techniques. It is possible that a polynomial function of multivariables, y=f(x_1,x_2,…,x_n), is fitted to tabulated data by using a least squares criterion. This function greatly reduces the storage. In this paper two regression methods are investigated to form the function. These two methods are based on the following functions respectively. f_1(x_1,…,x_n)=ΣA_<p_1p_2…p_nx_1^<p_1>x_2^<p_2>…x_n^<p_n> f_2(x_1,…,x_n)=П^^n__<j=1>(Σ^^m__<i=0>B_<ij>x_j^i) The possibility of regressing, number of sample data, and number of multiplications for function f_1, f_2 are examined. f_1 can regress any data, but f_2 can not always regress it. The necessary number of sample data for f_2 is less than that for f_1. The number of mutiplication in f_2 is also less than that in f_1. There is the maximum number of independent variables and the maximum degree of a polynomial, when the number of multiplications is restricted. The relations between the number of multiplications and the number of independent variables or the maximum degree of a polynomial are shown by tables. The two methods have been applied to the data of an air-cooled packaged air conditioner. The standard deviations by the two methods are within permissible limit (3% of deviation in data).

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This paper describes a study on one of the method of controlling particlate air pollutant emissions, the Steam Injection & Charge Method. In this method, steam is injected into dust laden air, condensed water droplets including dust particles as nuclei are charged by corona discharge and precipitated to the inside wall of precipitator duct by the effect of electrostatic diffusion. In our previous report, the experimental results and analytical equations on the relation between collection efficiencies and operation factors were presented for mono-dispersed test particles of low concentration. In this paper, We investigated on the effects of size distribusion and concentration of dust particles on collection efficiencies. (1) Theoretical calculations The differential equation of growth rate for water droplets including dust particles as nuclei, the equation of charge on droplets and the differential equation of electrostatic diffusion of multiple-size droplets were combined and calculated numerically by digital computer. The size distribution function of dust particles were assumed to be log-normal. The calculated results showed that; 1) As the concentration of dust particles increased or the deviation of size distribution of dust perticles increased, the deviation of size distribution of droplets increased. Collection efficiencies of dust particles advanced as the deviation of size distribution of droplets increased in any operating condition. 2) As the concentration of dust particles increased, the total volume of water droplets increased even in conditions of same condensed water volume by the effect of the volume of dust particles. The increase of total volume of water droplets brings advantage of collection efficiencies as reported in our previous report. (2) Experiments To examine the propriety of theoretical calculations, experiments were made using poly-dispersed DOP (Dioctylphthalate) aerosol as test particles. Water droplets in sample air were collected and dissolved in a solution of ethanol and distilled water, the solution was distilled to oil in water type emulsion and the turbidity was measured to know weight percent of DOP. The size distribution of DOP aerosol was measured by impactors. They obeyed to a log-normal distribution of geometric mean diameter 0.66μm and geometric standard deviation 1.77. Collection efficiencies were measured in the range of mass concentration of DOP aerosol 0.05〜1.5g/m^3, precipitator duct length 2.4〜10.3m, inlet air velocity 0.5〜2.0m/s, steam injection rate 1/80〜1/10, corona current 2〜16μA/cm. Experimental results agreed with theoretical calculations within the experimental errors. To compare the experimental results of with and without steam injection, it was proved that the effect of steam injection on the advantage of collection efficiencies decreased as mass concentration of aerosol particles increased.

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The objective of this research is to develop the method of evaluating the design and the operation of air conditioning system. Fundamental method of evaluating the system is decomposing into basic components which have various characteristics respectively. Taking the system into consideration by the unit of decomposition, the system can be analysed and synthesized essentially and easily. Section 1 The author cites a simple design of air conditioning system for example and decomposes of power consumption to fundamental compositions and emphasizes necessity of developing the method of evaluation in air conditioning system. Section 2 Decomposition and evaluation of heat source system with compressor. Decomposition consists of two items. One is efficiency of motor and compressor and the other is power consumption of compressor. The efficiency is evaluated by the difference between actual value of efficiency and standard value of efficiency which is assumed previously. The power consumption of compressor is divided by compressor head. Compressor head consists of heat exchange head and original head which expresses the potential difference between design condition in room and heat source (or heat sink) condition. Heat exchange head is composed of upper pressure side and lower pressure side. The author shows the value of heat exchange head and original head in various heat source systems in table 1. Section 3 Firstly the author shows the characteristics of heat storage tank system. Comparing quantitatively the system with heat storage tank with the system without heat storage tank, the author gets timing relation between two systems. The author divides the characteristics of heat storage tank system into five items as follow. 1) Effect of the night off-peak electricity 2) Heat loss from heat storage tank 3) Variation of Compression efficiency and motor efficiency 4) Variation of supply temperature by mixing and heat loss in tank 5) Effect of heat recovery operation with heat storage tank These characteristics of heat storage tank system lead to the following simplified mutual relation. [numerical formula]

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Succeeding the paper of "the Method of Evaluating the Design and the Operation of the Air Conditioning System (Part 1), we evaluated the air conditioning system of the actual building on the basis of the algorithms which were stated in that paper. We got the various data which were measured and recorded hourly through a full year. Using that data, we analyzed and evaluated mainly power consumption of the central refrigeration system which were made up of refrigerating compressors, condenser-air fans and primary cooling water pumps. This paper is composed of the following items. 1) the description of the building and the air conditioning systems 2) operational characteristics of the system of the building 3) the evaluation of thermal storage tank system 4) the evalvation of refrigeration system In section 3), we analyzed and evaluated on the basis of measuring data about the following items; (a) heat loss, (b) night off peak electricity, (c) variation of supply water temperature, (d) heat recovery operation using thermal storage tank. In this system, total quantitative evaluation of the effect on using thermal storage tank system resulted in an additional power consumption of 1310×10^2kW・h/annual which resulted mainly from heat loss. In section 4), we analyzed and evaluated the refrigeration system on the basis of measuring data. This section is composed of the following items; (a) cooling water side, (b) heating water side, (c) compression efficiency, (d) assembling of the each items. Both the cooling and the heating water sides were divided into seven items and each items were evaluated quantitatively. Compression efficiency was evaluated by the difference between the actual value and 0.65. Finally we proposed the chart which explained the relation of the each items to total system and pointed out the importance of improving compression efficiency.

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A newly developed method, which can be used to find out energy and cost efficient buildings, estimates various energy conservation means. It also evaluates each effectiveness of them clearly and decides most desirable ones. This method applies two unique techniques as follows, 1) The architectural design and the building services equipment design are dealt with an integrated way. 2) To estimate energy conservation means, not only energy consumption (that is energy cost) but also the capital required are considered. In latter technique, the effect of each energy conservation means is shown as a two-dimentional vector on the graph, where the abscissa shows the capital required and the ordinate energy cost. The gradient of this vector is used as a criterion of effectiveness of energy and economy. The accumulated effect of some selected means is also drawn as a combined vector. By drawing several auxiliary lines on the graph, the payback period or the profit can be obtained. Finally, we can get the most suitable answer to the different philosophy of building owners. Applying this method, we studied some model buildings and represented several results and its considerations. Using this method, we can plan the energy conservation buildings which can be built at lower capital required than conventional ones.

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