When a utilities underground conduit is ventilated and a Partition Type Damper (PTD) is installed to provide a conduit with an air volume damper, pressure losses occur as reported in Part 1 of this paper. Outlined are the experimental results regarding pressure loss when a pair of PTDs is installed at specified intervals inside a circular duct. Under the condition that the ratio of the length of partition (Y_b) to the diameter (D) in the center of the air duct (C_r=2Y_b/D) is 0.245, when the length of the interval (SP) is more than twenty times the duct diameter, the pressure loss becomes twice as large as that of one PTD. However, when the length of interval is less than this value, the amount of pressure loss changes according to the length of interval. The authors see this cause is considered to be attributable to the location between the two PTDs which interferes with the downward airflow from the head PTD. Therefore, Providing coefficient of interference (ψ_<dx>) caused by the length of interval, the pressure loss in this case is expressed in terms of the following equation; (dP_d)_<dx>=0.202ψ_<dx>・P_v ψ_<dx>=2{C_0+X(C_1+C_2・X)} X=(SP/D-a)/b where, (dP_d)_<dx>: pressure loss when a pair of PTDs with C_r=0.245 is installed at a specified interval inside circular duct [Pa] P_v: kinematic pressure in air duct [Pa] D: diameter of circular duct [m] SP/D: nondimension length of interval a, b, C_0, C_1, C_2: constant value caused by SP/D (Refer to Table 1) Table 1 Values of application at C_r=0.245 [table]

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This study intends to suggest the method of calculation for the loads of hot water supply system in dwelling houses. In this paper, as the part one, we analyzed the data; temperature of hot water usage, volume of hot water consumption in each hot-cold faucet, etc., that obtained by measurement continuously conducted for over one year in the five dwelling houses. At the first, we studied about the period on seasons for hot water demands based on the changes of the air and tap water temperature and the hot water supply loads throughout a year in each house. From these results, we established the three seasonal terms; winter, summer, and middle season. Next, we analyzed the volume of hot water and energy consumption in each seasonal term and a year. And we showed the total mean and peak loads per flat and per day/or per hour in each group; Weekday, Saturday and Sunday and Holiday. We also analyzed the loads in each facility of the dwelling houses in the same manner as mentioned above, and showed the hot water temperature used in each faucet.

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The experiment of mass transfer in a turbulent flow, such as the dispersion of pollutant in a ventilated room mode, has implied the measurement of 3-D distribution of tracer concentration. However, a measurement with probes and sensors requires much of labor to obtain large amount of data for 3-D distribution; moreover probes can disturb the airflow. The work presented here describes the approach to mesure 3-D tracer concentration distribution through digital image processing by using aerosol particles as the tracer. The tracer particle images obtained in different depths illuminated with a laser light sheet are analyzed synthetically including the effect of ray extinction due to light scattering. The procedure to calculate concentration distribution is as follows; (1) Visualized images in different depths are digitized to gray levels with an image processor and spatially averaged for each small segment composed of several pixels. (2) The gray level data are corrected for spatial sensitivity distribution of the hardware and converted to luminous intensity using the calibration curves prepared. (3) The luminous intensity is corrected for the direction dependence of scattering intensity and the effect of light extinction is removed through numerical integration of turbidity following to the Lambert's law. The adequacy of the method was verified by calculating homogeneous concentration distribution. The result indicated that the method led to the relative error of several percent. The concentration distribution in a ventilated room model under three different conditions were measured as an application. The ventilated room in which the fresh air is supplied from an inlet on the ceiling and contaminated air is supplied from an inlet on the floor was modeled. The effects of the outlet height and a panel placed at the downstream of pollutant's inlet are studied through the comparison of concentration distributions.

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Thermally stratified storage tanks have been in use because of their high performance (heat storage efficiency). But in case of the destruction of the thermal stratification caused by the change of the supplying fluid temperature, it has been known that the performance of this type of heat storage tank drops drastically. In this paper, the temperature selective heat storage system is proposed to prevent supplied fluid mixing with stored other temperature layer in the thermally stratified stage. The temperature selective heat storage tank, or TSHST, consists of a main tank and a sub tank having several dampers which are easily opened and closed. The TSHST of 200mm width, 700mm length and 1100mm height was formed as the test model and water was used as the heat storage medium in this study. Experiments were conducted by changing such parameters as supplying method, temperature, flow rate and close sectional area of the sub-tank. The measurement of temperature distribution and the flow visualization by dyeing the supplying fluid were performed to examine the process of thermal storage. The results of these experiments indicate that proposed TSHST is effective to maintain the thermal stratification for a wide range of supplying flow rate even if the supplying fluid temperature changes.

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Including the previous report (Part 1), these studies aim to the suitable planning and operating conditions for small scale household wastewater treatment facilities with denitrifying function. Previous paper mainly took up the mutual relation between denitrifying ability, recirculation and redox potential level in compound wastewater. This paper attempts to discuss on the following items. 1. Comparative observation on denitrifying ability in each compound and existing municipal wastewater. 2. Interaction between water temperature, recirculation ratio and each nitrification, denitrification reaction. The following results were obtained in this experiment. 1. It can be considered in reaction proceeding etc. that there is no significant difference between compound and actual sewage water, if proper composition in compound wastewater is selected. 2. The reaction is affected by temperature considerably. It is desirable to provide about over 15℃ in reaction temperature and adequate recirculation ratio in nitrification, but higher temperature will be required in denitrification process.

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In the first paper, tables for estimating the PAL value, peak and monthly average heating and cooling loads for the office building were proposed. The present paper has prepared the same kind of tables for the shopping and hotel buildings which appears most popularly in those districts with district heating and cooling. An example calculation for two kinds of districts which are different each other from the viewpoint of yearly heating and cooling load pattern. It was clearly shown that a conventional estimation method of district heating and cooling load will lose the chance to select the best systems for energy conservation as well as the district environmental condition. The proposed estimating tables in two parts for three kind of buildings give a lot of informations for an optimal design of DHC systems.

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As the interaction of pressure loss of combined fittings has not been considered in building water supply piping design, the authors chose combined fittings which are frequently used and popular in buildings, and grasped the profile of interaction of pressure loss by the experiment of resistance characteristics for single fitting and combined fittings. The combined fittings for experiment consist of one tee and two elbows, or one tee and one elbow. The experiments are carried out for changing flow course and connective length between each fittings, the characteristics of interaction of pressure loss are shown, and the influence of relative sectional area and flow separation ratio are considered.

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Applications of the 2 degrees of freedom control which has two different stages, the first stage to decide the control aims and the second stage to carry out the actual control, are studied for air conditioning devices. At first a packaged air-conditioner is studied as an example mainly for the first stage where its parameter is automatically adapted to various control conditions in order to keen its operation stable. This method can be used in addition to the conventional PID or other controllers. Next an absorption chiller using a multi-input fuzzy controller based on the 2 degrees of freedom control is proposed in order to comprehensively achieve diverse aims like conserving energy and better reacting to load changes on the first stage. On the second stage, wellknown characteristics about the heat source are mainly used for fuzzy inference. Experimental results confirm that the proposed method surpasses conventional PID control.

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This study has been made on the mechanisms of head loss in turbulent flow, and shows quantitatively that head losses are caused by the flow impact of fluid with fluid or on the wall. Furthermore, the author has introduced theoretical equations which express loss coefficients in pipe and duct symmetrical combining junctions; The theoretical equations contain the coefficients which were determined on the basis of the experimental results of many researchers. These equations well represent the actual phenomenon.

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In order to use SET^* as a thermal index to the prediction of thermal sensation and the evaluation of thermal environment, it is necessary to clarify the correlation between SET^* and thermal sensation. In our previous papers, the regression line between SET^* and the whole body thermal sensation was shown as a result of the winter and summer subjective experiments, and the zone of thermal neutrality with thermal sensation votes ranging from 4: slightly cool to 6: slightly warm was concluded around 22〜26℃ SET^*. However, it has not been experimentally confirmed that the correlation between SET^* and thermal sensation is the same regardless of activity levels. This paper reports the results of a series of walking experiments and compares them with the results of sedentary experiments. In the walking experiments, 4 male and 4 female subjects were exposed to 10 different conditions ranging from about 18 to 31℃ SET^* for about 1hour, and they were made to keep on walking at the same place for 1hour. Metabolic rate of walking subjects was judged at 1.5met. The main results are shown as follows. 1) The significant correlations (R≧0.88) were found between SET^* and whole body thermal sensation votes for any male and female subjects other than one male who voted nearly neutral sensation in the range of 18〜31℃ SET^*. 2) Individual regression lines tended to converge at higher temperature side than neutrality. 3) The regression lines for each individual were very similar in both walking and sedentary experiments. 4) No sexual difference was observed in those regression lines as well as in the sedentary experiments. 5) The regression line resulting from the walking experiments was almost equal to the one from the sedentary experiments. 6) SET^* at thermal neutrality (TSV=5) calculated from the regression line was 24.2℃ at walking and 23.3℃ in a sedentary posture, so that the difference between two was within 1℃. As a result of this study, it has been experimentally proved that the value of SET^* at people feel comfortable is always the same under the condition of various metabolic rates.

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In this paper, in order to investigate the influence due to the difference of air supply direction in the fancoil unit (FCU) for the starting characteristics of the FCU system, a series of unsteady state numerical calculation for a room model was conducted. At first, prior to beginning the general study, the applicability of this numerical calculation method for a model room equivalent to that used in the experiment were examined. The results required in the calculation were compared with those in the experiment in some typical cases. As the results, it was confirmed that the numerical prediction using this numerical calculation method was available for this kind of room models. For the fundamental study, under the same air supply condition, in reducing the heat loss and reaching a set point of average temperature or PMV in occupied zone quickly, the superiority of the method of horizontal air supply at the bottom of fancoil unit (HASB) was confirmed in compared with vertical air supply at the top (VAST). Moreover, when the FCU system of HASB was operated under the condition identical with the transient characteristics of VAST in regard with average temperature or PMV in an occupied zone, it was confirmed that the air supply temperature and heat loss could be decreased in HASB in compared with VAST as well as in the steady state.

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