This paper reports on calculation method for exact room air temperature distribution which caused by heat convection by maximizing or minimizing the total heat transfer amount to horizontal direction in satisfying heat balance equations of room air and walls. This heat amount can be calculated in regard to the stability and instability between adjacent air masses in the room. In the part 1 of this paper, the values of parameters in this calculation method were determined by the series of model experiments. Furthermore, verification of the calculated and measured values of room air temperature distribution was made with varying the heat amounts of heater in model.

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The calculation method of vertical room air temperature distribution in large spaces which caused by heat convection was proposed in the part 1 of this paper. In this paper, verification of the calculated and measured values of room air temperature was made in the case of varying shape and scale of model. Furthermore the actual measurements were made in the actual large space building which equipped with radiant heating panels on ceiling to examine the accuracy of the calculation method in applying to larger building than model.

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In the previous report we published results of actual measurements of variable air volume (VAV) systems which handled transmission loads with constant air volume, and also solar and interior loads with VAV. In this report we measured VAV systems equipped in the northeast and the southwest zones of the existing building which were designed to handle heating loads by transmission with radiator, and cooling loads by transmission, solar and interior loads with VAV. The air conditioned area of the northeast zone was 3193m^2, and that of the southwest zone was 3140m^2. The measurements were performed during one week in January, August and November respectively. As to these studies, some results are shown as follows: 1) The measured values were nearly equal to the theoretically calculated supply air quantity, power input to fans and cooling and heating coil loads. 2) In the measurements during one week in August, the cooling load from outdoor air reduced to about 32%, and in January the weekly heating load reduced to about 28% by employing air-to-air heat exchangers. In November, the weekly cooling coil loads were zero by using free cooling. 3) The proportion of fan power input to the total energy consumption of VAV systems was large. Therefore the outlet air temperature should be set as low as possible and supply air quantity should be reduced. 4) According to the results of the theoretical calculation of power input of refrigerators, fans and pumps, VAV system with speed control of fans was smaller in the total energy consumption in comparison with other air conditioning systems.

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Since the committee report of the Society of Heating, Air-conditioning and Sanitary Engineers of Japan published the Standard Weather Data for air-conditioning load calculation in 1974, the data of seven regions have been produced by the same method. We set up the weather data of Fukuoka, Kumamoto and Kagoshima for the purpose of arrangement the weather data in Kyushu area and studying the characteristic of climates of the three areas. This report illustrates the process of the production of the data of the three areas mentioned above, we also checked the method of data setting proposed by the committee report. At the same time proposed our new method, for example the method of using Atmospheric Transmissivity when calculate the DM value. We hope this data will be used on a reference for studies of other areas in the future.

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We have investigated the tendencies of the variances of the nine meteorological elements involved in the standard weather data of Fukuoka with the spectra, the patterns of the daily or yearly variances and the probability density functions. So the yearly periodical variance of the dry-bulb temperature, the absolute humidity, the horizontal diffuse solar radiation and the atmospheric pressure are shown very clearly, and it appears that the dry-bulb temperature, the normal direct solar radiation, the horizontal diffuse solar radiation and the relative humidity have the clear tendencies of the daily periodical variances. We have also compared the climates of the six cities in Japan -Sapporo, Tokyo, Osaka, Fukuoka, Kumamoto and Kagoshima-, using the probability distribution function of the daily average values of the six meteorological elements. Lastly we have extracted the components of the sea-breeze and the land-breeze in the standard weather data of the six cities, and it is concluded that in these cities except Kagoshima the directions of the sea-breeze and the land-breeze are decided by the directions of coastlines, and their velocities are decided by the distances from seashores. And it is appeared that in Kagoshima these relationships are not established because of the particular geographical environment.

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In this report, we calculated the air-conditioning load of the ordinary office rooms of six regions (Kagoshima, Kumamoto, Fukuoka, Osaka, Tokyo and Sapporo) to compare with the characteristic of climate. The computer program of HASP/ACLD/7301 was used and used the Standard Weather Data which was commonly used and the weather data in Kyushu area which we set up. We also examined that the relation between the shapes of building and air-conditioning load. As the results of comparison of three areas in Kyushu, namely, Fukuoka, Kumamoto and Kagoshima, heat extraction rate in summer was almost equal, heat supply in winter differed in each area and that of Kumamoto was the largest. When we compared the year-round air-conditioning load of five regions, Tokyo, Osaka and the three areas mentioned above, that of Osaka was the largest and the rate decreases in the order of Kumamoto, Fukuoka, Tokyo and Kagoshima.

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A model experiment was made on the behavior of the airflow in a natural draught cooling tower. The height of the model tower is 800mm, the diamter is 672mm at the base and 424mm at the top. The heat exchanger in the tower is simulated by an electric heater. A glass wool filter is placed close to the heater to give analogous resistance to the flow. The wall of the tower is made by a transparent acrylic plate for visual observation. The streamline of the flow was observed by smoke method. During measurement of velocity and temperature of the flow, the tower was thermally insulated by polyethylene sheets for diminishing the heat loss through the wall. The temperature of the air was measured by copper-constantan thermocouples. A hot wire system based on heat wake method was used for measuring low velocity of thermally fluctuating flow. The conclusions obtained are as follows. 1) The flow separates at the upper edge of the air inlets. The separation results in a ring-shaped dead air region near the wall inside the tower. A bell mouth attached to the inlets is effective to reduce this region. 2) The velocity distribution at the heat exchanger is affected by heating distribution, resistance distribution and the height of the air inlets. 3) The flow after the heat exchanger is accelerated by buoyancy. The effect of buoyancy makes the velocity distribution in the outlet plane agree well with the temperature distribution in the same plane, i.e. at the outlet, the velocity is high where the temperature is high, and the velocity is low where the temperature is low. 4) When the air temperature is high and the flow rate is low, the rising airflow converges exceedingly. This induces the flow of cold air falling down into the outlet from outside. The vertical partition plates installed radially in the tower prevent the occurence of this air intrusion.

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In this paper we describe an experimental study of self-siphonage of fixture traps. A DWV system in Japan has been changing to a single-stack system from a fully vented system. Therefore, it is hardly to use an individual fixture venting which is the most effective prevent method, not to be adopted a fixture drain one size up or traps of various types besides a P- or S-trap in Europe. It is defenseless for self-siphonage under present conditions. Then, in order to examine for useful prevent methods, we investigated first the effect of elements of piping constitutions of a residual seal depth by characteristics of flow phases in a fixture drain and a residual seal rate. From the results, it is clear qualitative efficiencies on self-siphonage to provide the lavatory with the overflow pipe, shorten a vertical length between the lavatory and the P-trap, enlarge the trap seal depth and the fixture drain diameter and make gentle gradient. However, we think the privent methods by means of the regulation for pipings. Next we took notice of the trap form, and the result that the bottle traps had the best performance was obtained after the experiment on the various trap forms. So, we carried out the experiment to estimate the bottle traps for the various pipings. The result was the minimum residual seal rate: 0.62 and the maximum standard deviation: 4.8mm. This shows it is possible to prevent a self-siphonage as the bottle trap was provided under the lavatory. It is necessary to examine for a self-cleaning faculty of the bottle trap in future.

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In the preceding report, we investigated performance of a practical magnetic filter in which nets of ferromagnetic wire are arranged parallel to air flow and are positioned at equal distances perpendicular to the direction of magnetic field (parallel stream wire netting type of magnetic filter). This paper presents a semiexperimental study of collection efficiency of a magnetic filter in which air flows parallel to magnetic field and in which nets of ferromagnetic wire are positioned at equal distances perpendicular to the direction of magnetic field and of air flow (perpendicular stream wire netting type of magnetic filter). Dependence of collection efficiency on air velocity, strength of applied magnetic field, diameter of wire and packing density are investigated. Semiexperimental analyses of this type of magnetic filter have shown as follows. Firstly, capture radius (single fiber collection efficiency) is a linear combination of the single fiber collection efficiency due to magnetic force effect and that due to inertia effect. The collection efficiency at low velocity of air flow depends mainly on the magnetic force effect and at high velocity of the flow depends mainly on the inertia effect. Secondly, the pressure drop of this type of magnetic filter can be estimated by a semiexperimental formula based on the drag theory.

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Throughovt of our preceding papers, collection efficiency and pressure drop were investigated for clean magnetic filter of various types. For practical purpose, however, dust loading effects on filter performance, in other words, the penetration and pressure drop after the filter has been operated for a certain length of time, are more important properties to be examined. The purpose of this paper is an attempt at a simple semianalytical treatment of the dust loading behavior. Time dependence graphs of filter performance are obtained from solution of semianalytical equations describing the physical situation in high-gradient magnetic filtration (HGMF). These graphs tell us how conditions within the filter change with time and express the concentration of air-borne particles as a function of time and distance through the filter. For a given set of conditions, the filter performance changing with time can be predicted by the time dependence graphs based on experimental data of the penetration and pressure drop per unit thickness of the dust loading magnetic filter. Experiments are also made on dust dislodging efficiency by backflushing with a pulse of compressed air. It is shown that the magnetic filter performance can be enhanced by improving the dust dislodging efficiency.

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A two-dimensional and very fundamental ventilating system of square chamber having an intake and an outlet being used first by Nomura, Matsuo and Kaizuka, and thereafter by Yoshikawa and Yamaguchi is reexamined experimentally as well as numerically for low Reynolds number regime. Regarding to the numerical method, we have developed an unsteady calculation scheme introducing a new correction for inadequacy appeared in velocity bounday condition of usual MAC method. The usual MAC method has zeroth-order accuracy at adjacent points of wall boundary and second-order accuracy for the rest of domain whereas the new scheme simple in making correction introduces the first-order accuracy at wall adjacent points, thus contribute to maintain a good accuracy for a whole domain. The unsteady calculation exhibits mechanism of the initiation and growth of circulation vortices and its influence to the main ventilating flow. The range of Reynolds number calculated is from 1 to 200. In order to confirm similitude expressed by Reynolds number, we have used water and air as working fluids in model experiment. The test chamber for air is of 18×18cm cross-section and 90cm depth with 2cm width of an entrance and an exit. The flow of water was observed in a chamber of 9×9×27cm having 1cm width of an inlet and an outlet. To eliminate the side wall effects and non uniformity of the inlet velocity in transverse direction, the width of each chamber was made wide enough compaired to its cross-section, and heedful arrangement was made in introducing a flow into the model chamber. Flow fields were determined by tracer methods, zinc stearic acid powder for air and aluminum powder for water. By using strobo-light of 16mm movie-projector and shutter of camera, a wide range of flow speed was determined by one photograph. The model experiment ranges from 30 to 200 in Reynolds number and the results agree well with the numerical calculations. The above results, both calculation and experiment, indicate that with respect to the growth and decay of large scale vortices and the direction and intensity of main ventilating flow, the flow characteristics change quite distinctly with Reynolds number in the range of 1 to 200. This result differs from the one with the value of Reynolds number over 10^8 where flow pattern is reported to be independent of Reynolds number. To the range of Reynolds number calculated, the present method of solution is founded to be more suitable than a combined method of unsteady up-wind and vorticity-stream function and a weighted-residual finite element method. It is seen to cover a whole range of laminar flow including the first appearance of a transitional fluctuating flow.

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Cooling Power between the thermal environment and the black cylinder as human model, has been analyzed and experimented with two solid cylinders made of aluminium(Al) and copper(Cu). Its purpose is the evaluation of room thermal environment. Size of the cylinder is diameter=0.05m, length=0.2m. The fitness for the theoretical analysis of this paper is verified by the experimental results. It is understood that Cooling Power of the black cylinder evaluates the thermal environment, theoretically and directly, and expresses synthetically air temperature, air velocity and heat radiation of evironment. When Cooling Power of the black cylinder is compared with Operative Temperature of the black cylinder, or measurement of Globe Thermometer, Cooling Power can express air velocity better than the other evaluation methods and it is good to evaluate the human environment.

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For the design of two dimensinal push-pull hoods based on the "Flow Ratio Method", Optimum sizes of hoods and required flow volumes are obtained by using the experimental judgement as well as iterative calculations until now. From the investigative results of conventional design method, some equations which satisfy to design most economical push-pull hoods without applying iterative calculation can be derived. In light of these facts, this paper first describes the equations on the economical design of push-pull hoods, and next does the procedure of design method in order to get optimum design values.

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