In the circumstance of the social demand for residential environment progress and energy saving, we researched all Japan residential energy consumption. We had questionnaire research about 1400 house holds from nine cities, five various types of residences. Using that data, we got the coefficient of correlation between the quantity of energy consumption and income, residential area, climate condition, etc. And we tried to get the data that shows how much energy is consumed for the purpose of heating, cooling, hot water supply, cooking, lighting, power, etc.

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In this paper following the previous ones, some aspects of the flow patterns of the miter-bends with different bending angles Θ's and areal ratios λ's in laminar and turbulent flow are reported. The miter-bends under experiment have rectangular cross-sections. First, the velocity distributions were measured in turbulent flow. The velocity distributions in the center-line plane of the miter-bend change more severely in the neighbourhood of the bending part than those in the plane perpendicular to the center-line plane independently of Θ and λ. Generally, the variations in velocity distribution measured in the center-line plane increase with the increase of Θ when λ remains constant and with the decrease of λ when Θ remains constant. The variations in velocity distribution due to the presence of the miter-bend persist broader in the downstream section of the miter-bend than those in the upstream section. In the downstream section they extend further downstream than the variations in static pressure distribution due to the presence of the miter-bend. The measured velocity distributions in the center-line plane of the miter-bend in the neighbourhood of the bending part coincide fairly well with the computed results obtained by the analysis based upon the two-dimensional potential theory with separation at the convex corner, and further they coincide qualitatively with the results obtained by the numerical analysis in two-dimensional laminar flow. Next, in laminar flow, in order to clarify the relation between the variation of the length of the upstream conduit l_<10>/h_1 and the flow pattern, the experiments were made on the miter-bends with rectangular cross-sections and with the nozzles at the end of the upstream conduit. The flow patterns in the upstream conduit are influenced more remarkably by the change of l_<10>/h_1 than that in the downstream conduit. The flow mechanisms are considered together with the results obtained by the numerical analysis. The measured separation points of laminar boundary layer developing on the walls upstream of the concave corner are compared with the results obtained by the analytical method.

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Experimental studies on a stratified-type heat storage water tank were carried out to obtain the principle which can predict thermal characteristics of the vessel for given shape and input conditions. The unit length of the experimental vessel is 0.8m, and input flow rate, diameter of inlet and outlet, and the length of the vessel ware varied considering the real scale heat storage tank under the law of similarity using Archimedean number. A model which explains the mixing process in the vessel is proposed. The model consists of three regions, i.e. [○!A] perfectly mixed region at the top, [○!B] one dimensionally diffused region at the intermediate, and [○!C] dead region at the bottom beneath the outlet. From the experimental observation it is assumed that, in [○!B] region, thermal diffusion is of the order of molecular one in vertical direction and water temperature holds uniform in horizontal direction. Comparing the values calculated by the proposed mixing model with experimental data, an equation which predicts the depth of [○!A] region was obtained as follows. Ar_<in>(l/d_0)^2=0.41 where, Ar_<in>=(Δρ/ρ_0)gd_0/(u^2) l: depth of perfectly mixed region d_0: diameter of inlet Δρ: density difference of water between inflow and initial vessel condition ρ_0: density of water at initial vessel condition g: gravity acceleration u: velocity of inflow

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For the cooling and heating of a large air space, the region subjected to air-conditioning should be restricted within the occupied zone from the viewpoint of energy conservation. Fortunately, we happened to have the occasion to carry out the scale model experiments related to the cooling and heating of two large air spaces. One is the assembly hall of Daisekiji Temple. The dimensions of air space is about 110m×83m×66m (height). The total number of seats account to 6000. The 1/100 and 1/30 scale models were constructed in order to decide the design conditions of cooling air distribution system. The other is the supreme court which is composed of the lower and the upper parts. The shape of the lower part is cubical, 22.6m×22.9m×8.5m (height), and the upper part is cylindrical with 15m diameter, 16m height. The 1/10 scale model was used to carry out the experiments to confine hot air within the occupied zone by means of horizontally projected air curtains. The main conclusions obtained by model experiments are as follows. 1) The cold air projected vertically from the floor level stagnates within the middle height of air space. The air distribution is uniform within this region. 2) The heat gain through walls is reduced to less than 80% compared with that of uniform cooling in the whole air space. 3) Depression of hot air current can be successfully done by the air curtains projected horizontally located at the upper part of the occupied zone. The maximum effect of air curtains is attained when outlet velocity is about 7m/s. 4) The temperature of the occupied zone can be kept higher by increasing the outlet velocity of hot air projected downward. 5) The vertical temperature difference can be reduced by floor panel heating.

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The separation point of the boundary layer in the main conduit, whether the flow was laminar or turbulent, was studied by the experimental and by the theoretical method as for the case where the branching part was situated in the region of the inlet length.

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Investigation of the fixture usage and water consumption in the buildings and examination for its causes will be more and more necessary for the collection of the minute designing data. By such point of view, this paper presents the result of an investigation of the theater and summerizes the analysis for the results of the data which was obtained from the investigation of three theaters including the first part of this paper. The result shows some topics as follows, 1) the peak of the frequency of the fixture usage was happenned at immediately before and after the play time and the rest time. 2) the frequency of the fixture usage was influenced by the layout of the fixtures. 3) the frequency of the fixture usage was influenced by the difference of the type of fixture (Japanese and Western). These topics will be usefull for the design of buildings and services in future.

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At the scene of a fire, generated smoke particles decrease the visibility and obstruct to find a way of escape. They also disturb firemen's fire-fighting and rescue activities. Recently, the smoke extinguishing equipment utlizing space charge effect were developed as a measure of recovering visibility in the scene of a fire. This equipment is composed of a fan and a corona discharge electrode to give electrostatic charge on the smoke particles, and has not collection plates unlike electrostatic precipitators. It has been in field use as a portable smoke extinguisher for fire-fighting. In this paper, we investigated the mechanism of smoke extinguishing phenomena theoretically and experimentally. At first, We calculated the rate of number concentration decrease of smoke particles as a result of deposition on a wall and coagulation between particles. Deposition owing to electrostatic dispersion, gravitational force and gradient force and coagulation owing to thermal diffusion, turbulent diffusion and electrostatic force were considered. The calculation based on a few assumptions showed that main mechanism of the decrease of smoke particles are the deposition of charged particles on a wall by the effect of electrostatic dispersion and electrostatic coagulation between charged and uncharged particles. Then, we made differential equations which express the change of number concentration of charged and uncharged particles, average diameter of charged particles and average charge on the particles. These four fundamental equations contain four dimensionless parameters, penetration of the equipment, electrostatic dispersion parameter, coagulation parameter and smoke generation parameter. The value of these parameters decide the rate of smoke extinguishment and terminal turbidity in a chamber where smoke particles are generated at the constant rate. Subsequently, We made a few experiments of smoke extinguishment to prove the theory in the case of constant smoke generation and no smoke generation in a 1.8m cube chamber. The mean mass diameter of smoke particles was 0.18μm and 0.48μm, and the initial turbidity in the chamber was 0.8m^<-1> and 1.6m^<-1> respectively. The turbidity in the chamber was measured continuously by a transmission meter. Experimental results agreed well with the theoretical values and our theory was verified. Finally, We examined the characteristics of this smoke extinguishing equipment by unmerical calculations of fundamental equations. Calculated result showed that the visibility recovery is quicker and the terminal turbidity is lower in this equipment than the case of diffusion ventilation by the fan of same flow rate. High penetration of smoke particles in the equipment are desirable for excellent performance.

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Detailed design of air-conditioning and heating system is completed through various decisions on various stages. These stages are divided into three stages, such as "specification and usage of a building", "air-conditioning and heating system, and zoning" and "subsequent stage after decision on each load imposed on various equipments." This paper describes the last stage evaluating method for that. Section 1: The author classified various functions which exist between the stage after decision on each load imposed on various equipments and practical air-conditioning and heating system. Items of the classification are composed of heat exchange, transportation, equipment and its efficiency, etc. Loads, energy consumption by funs and pumps and equipment were classified into fitted items of the classification. Section 2: The author studied function of flow rate which occupied a main portion in energy consumption by funs and pumps. Function of air flow rate is classified into an amount of heat exchange (sensible and latent), satisfaction grade of air stream in a room, variation in sensibility of room environment to difference between load and amount of supply, and eliminating rate of dust and various gases. As for function of water flow rate, only heat exchange was taken into account. Section 3: The author made "a chart for analysis of energy consumption by funs and pumps" in order to show various items of the classification and flow rates of air and water to electric power consumption by funs and pumps, studying supposed air and water systems by means of the chart for analysis mentioned above.

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This paper classified and evaluated mainly actual results of annual energy consumption by funs and pumps on a standard floor in a building, according to the algorithm described in the third report. Section 1: An outline of air-conditioning and heating system in a building is described. Section 2: Data by actual measurement, and a method on system simulation for estimating data which couldn't be actually measured are described. Section 3: Power consumption by funs in air-handling units, fun-coil units and ventilating systems was classified and evaluated. Materially, the annual power consumption by funs was classified into items such as overall efficiency of fun, heat exchange and transportation, etc., being evaluated on the basis of relations between each item and its fitted load. Section 4: Power consumption by pumps was classified and evaluated, being based on measured data of each total flow rate of chilled water and hot water run in air-handling units and fun-coil units. First, consisting process of measured flow rate of a total chilled water system was showed. Second, annual actual measurements were classified according to classification items. Third, referring to a chart for analysis of energy consumption by pumps, each item was positioned in an actual system and evaluated together with related items. As a piping system for chilled water in the air-conditioning and heating system described here is an open type, energy consumption by position head occupies a large portion. This paper described those evaluations and methods for solution.

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The induction characteristics of diffusers having single primary air inlet nozzle (DIFFUSERS TYPE-I) was reported in the preceding paper. In this paper, diffusers to which double inlet nozzles were attacted in the opposite direction (DIFFUSERS TYPE-II) were tested for the purpose of improving axi-symmetricity of swirling flows inside them. The induction characteristics and flow patterns of DIFFUSERS TYPE-II were compared with those of DIFFUSERS TYPE-I. The results are as follows: 1) Both types of diffusers show almost same results concerning with total pressure losses. 2) The performances of DIFFUSERS TYPE-II are slightly better than those of DIFFUSERS TYPE-I concerning with induction efficiency and μ vs. |p_<t2>| relations. 3) In case that cross-sectional areas of annular channels of DIFFUSERS TYPE-I become smaller, swirling flows inside them become impossible to treat as axi-symmetrical flows. 4) Reversed flows from the open end of outside cylinder toward the end of inner cylinder are observed in case of no secondary flows (μ=0). 5) As the rate of secondary flows increases, the flow patterns gradually approach to the solid body lotation

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In the previous report, 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, when the area ratio of orifice to pipe are varied respectively, losses and discharge coefficients, and discharge direction are investigated experimentally and theoretically. Well, in order to relate this study to the uniform outflow from a perforated conduit or a slot, it is necessary to clarify a mutual interference by orifices. Then, in this paper in the case when two orifices are holed on lateral wall of pipe it is experimentally tried to make clear how a relative spacing between orifices has an effect on stream. Moreover, the experimental results between one and two perforated pipe are compared and discussed. The results are as follows: 1) Discharge volume from orifice is generally more quantity at downstream than at upstream, and it is influenced by a spacing between orifices. 2) Main pipe losses due to upstream orifice increase with decreasing spacing between orifices. This is because main pipe losses are considerably affected by downstream orifice. Nevertheless, when the spacing between orifices becomes to be L/D_0≧6, it is independent of downstream orifice. 3) A maximum value of main pipe losses due to downstream orifice exists in the region of L/D_0=3. 4) Main pipe losses except a friction loss in the main pipe due to both upstream and downstream orifices increase with decreasing spacing between orifices. The values in the cases of L/D_0=1, 2, 3 are almost equal. 5) Discharge losses are comparatively independent of spacing between orifices.

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