In order to estimate heat and moisture characteristics of indoor environment with air flow window system, a series of numerical analyses considering radiant heat exchange was performed. Proposed calculation procedure based on heat and moisture transfer equations within the hygroscopic region to be applicable to standard single glazed window, double glazed window and air flow window was verified with a certain accuracy by field measurement data. To quantify the performance of different window systems, numerical experiments based on design of experiment theory were carried out. In addition, to evaluate radiant environment of perimeter area, PDM (Perimeter Distribution of MRT) was proposed with some calculation examples.

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Recently, wooden dwellings in Hokkaido become more airtight. As concern for indoor air quality has grown, so too has the need to measure interzonal airflows in buildings to asses the distribution of outdoor air. These airflows can be evaluated by using the multiple tracer gas techniques. The balances of tracer gases are expressed by a set of differential equations. In such a case, we have to obtain the suitable time T_s, to calculate the interzonal airflows using the above equations and mass balance equations of airflow rates when the tracer gas concentrations were measured in each rooms. In this paper, we have a set of mathematical solutions for changes of gas concentration for 2 Rooms Model and a set of mathematical solutions for changes of gas concentration for 3 Rooms Model. These solutions are approximated by exponential functions according to the number of rooms. 1) In the case of 2 Rooms Model, the approximated functions for changes of gas concentration have two exponential functions. They have the exponent a and the exponent b(a<b). The time constant T_a and T_b are defined like T_a=1/a and T_b=1/b. The suitable time T_s to calculate the airflows is obtained between the time constant T_a and the time constant T_b. Because the beginning time to calculate them has to be set after the time to acheive adequate mixing in rooms. When the time to calculate them become larger than the time constant T_a, the influence of the function of exponent b become negligible. We have to finish the evalution of airflow rates before that. Seventeen multiple tracer gas tests were conducted by using the above method. 2) In the case of 3 Rooms Model, the approximated functions for changes of gas concentration have three exponential functions. At the first step, airflow rates are calculated from 9 tracer gas concentrations. After that, the tracer gas concentrations are calculated at the one sampling interval late by using the approximated functions. The measured gas concentrations are compared with the calculated values at the same time. If the calculated values and the measured values do not agree within a present criterion, the above procedures have to be repeated at the next one sampling interval. If the values agree within the present one each other, the evalution of airflow rates have done. Fourteen multiple tracer gas tests were conducted by using the above method.

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The authors compared various methods of outdoor design conditions for heating and cooling loads by using Tokyo hourly weather data for 15 seasons from 1972 to 1987, observed by the Tokyo district meteorological observatory. The best method is found on heat load taking account of building and operation schedule and the better method is based on outdoor temperature. TAC method is recognized too safe outdoor condition as compared with other methods. The authors propose a simplified seasonal heating and cooling loads calculation method. At first, accumulated distribution curve of daily total loads prepared by accurate computer simulation loads is divided to several sections and each section has typical outdoor condition. Secondary, by using each outdoor condition, periodic heat load calculation is made and weighting factors are multiplied to each heat load. Then seasonal heating and cooling loads are accomplished. Utilizing this method, heating and cooling capacity load and seasonal load can be calculated easily and this method is proved to be accurate comparatively.

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The results of indoor experiments with model regenerators of open cycle solar absorption dehumidifying and drying system consisting of regenerator, heat exchanger, dryness storage tank and dehumidifier are described. It has been difficult, in the past outdoor experiments, to identify the performance of regenerator because of strong variation in ambient conditions, especially wind speed. The influences by air volume and air velocity with the constant temperature of regenerating surface and controlled flow rate of solution on the regenerating performance were examined by the indoor experiment with the model regenerator of open-end type under the steady state conditions. The results showed that the influence of the air volume on evaporation rate could hardly be observed with different heights of the air space and regeneration rate with higher air velocity turned out greater in the case of a given air space. Furthermore, we proposed a new method to obtain the concentration of LiCl solution used as liquid desiccant continuously and easily without extracting solution during operating hours in reference to the standard concentration curves for LiCl solution prepared beforehand by measuring electric conductivity of LiCl solution. In the actual experiments, concentration value could be obtained by this method and continuously recorded. The relationships among non-dimensional numbers calculated from the results of experiments were slightly different from the general mass transfer equations for the laminar and turbulent flow of forced convection as found in literatures in the air velocity range higher than 0.5m/s, but considerable deviations were found in the lower air velocity range.

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In oder to obtain basic design data of water supply systems in apartment houses, the authors have investigated water consumption in the Metropolitan apartment houses. In this report, the authers compare the investigation results in 1988 with the results of examination in 1974, and also describe hourly and daily change of water flow rate, peak flow rate, instantaneous flow rate, etc. The results are summarized as follows; 1) In the household water consumption, the peak flow rate is larger in the evening than in the morning. 2) Especially in the small scale apartment house, this survey has proved that the value suggested by Hunter's simultaneous water flow rate was unnecessarily large. 3) In the case of small scale apartment house, there is a possibility of the insufficient capacity in water supply system designed by commonly used peak rates. 4) Automatic measuring systems introduced here were an extremely useful method for the water consumption survey of individual pipe line and continuous measurement over the long period of time.

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This report describes for the surveying research for the purpose of examinning the measurement system manual for cold and hot water supply in consumption in a single men's dormitory. Continuous automatic measurement was carried out for 4 lines of cold water system (total consumption in the dormitory, laundry, kitchen and bathroom), and 1 line of hot water system (bathroom) in one week for the single men's dormitory which accommodates about 80 persons. The measurements were carried out in winter and summer seasons. By these results were compared and analized, the authors grasped the trend of consumption.

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For the purpose of obtaining fuodamental data required for the designing of Heat Pump System, two hotels and residential houses were surveyed about the quantity and temperature of water for various uses. It was found that the temperature of waste water from the guest rooms was more than 30℃ all the year and the most calorie (70〜90%) spent for heating water remained in the waste water. So it was adequate to the heat source for the Heat Pump. And it was assumed that the mechanical trouble caused by fair amount of hair. On the other hand, the combined drainage of residential houses was of low temperature, low calorie and bad quality. Therefore it was inferior compared to the waste water of the hotel in quality for a heat source of the heat pump.

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In the current authorized method of determining fiber concentration of airborne asbestos in workplace, the numbers of asbestos fibers in filtrated samples are counted by a qualified man with a phase-contrast-microscope. This method needs skill and has poor objectivity and reproducibility. In this paper, we propose a system to count asbestos fibers automatically using the technique of image processing as one of the means of solving these problems. The system consists of a phase-contrast-microscope, a CCD camera, an image processor (512×512 pixels, 256 gray levels), a microcomputer and a hard disk drive unit. The hard disk can store about five hundred images. The time required to store 100 images manually in the hard disk is about 30 minutes and the automatic processing time of a single image is 3〜5 minutes. The identification of asbestos fibers is based on the guideline of the AIA (Asbestos International Association). Fibers that satisfy all the following conditions should be counted as asbestos fibers. They should 1) be longer than five micrometers, 2) be thinner than three micrometers in average diameter, 3) have a length-to-diameter ratio higher than three, and 4) have no sticking particle larger than three micrometers in diameter. A fiber with some branches should be counted as a single fiber. In case fibers aggregate, each elemental fiber should be identified separately. If the aggregate is too complex to be separated, it should not be counted. The counting processes of the system are summarized as follows: 1) Microscopic images to be analyzed are stored in the hard disk manually because the automation of the selection of adequate visual fields and the focusing involves great difficulties. 2) The images stored in the hard disk are analyzed automatically one by one. The analyzing routine includes pre-processing routine and counting routine. The pre-processing routine includes shading correction, thresholding and the restoration of fibers broken through the thresholding. In the counting routine, the shape of fibers are approximated by polygon and the guidelines are applied to the polygon. To check the ability of the system to recognize various shapes, the illustrations of asbestos fibers shown in the guidebook were counted by the system. The result showed that the system could recognize almost all shapes but for some exceptions. To verify the practicality of the system, we compared the values between by the system counting and the visual countings by three qualified men in different visual counting laboratories. The result of the comparison showed that there seemed to be some significant differences in among the counting standards of each laboratory. In the current authorized method, counting results depend significantly on counting men or laboratories. Since the counting standard of the automatic system is always constant in principle, the system should be valid for monitoring long-term fiber concentration of asbestos in either workplace or the atmosphere.

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This paper deals with soil for the heat source of heat pump on cold regions, and the amount of long term heat extraction and storage were estimated through experiments and numerical calculations. The experiments were conducted on long term ground heat extraction and storage using a vertical concentric steel pipe which were 20 meters long and φ60mm in diameter. Seasonal changes in the amount of heat stored and extracted, and the soil temperature were measured using glycole solution kept at a specific temperature of either 0℃ or 30℃. The average heat extraction rates among initial three months were 105kcal/h on continuous heat extraction and 205kcal/h on repetition heat storage and extraction. These values divided by temperature differences between circulating glycole solution and initial soil temperature give heat transfer rates of 17kcal/h℃ and 21kcal/h, respectively. This indicates that thermal storage in summer season enlarged the heat extraction rate by 25〜30per cent. Numerical calculations, using a model of a three-dimentional finite difference equation, were developed and carried out to analyze and compare the results and experiments. Results of calculations show a good agreement with the results of experiments. This indicates that it is possible to estimate the amount of heat storage and extraction by using the sensible heat conduction equation in this case. We also calculated about the effects of thermal recharge in summer season and the influences of characteristics of soils.

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Simplified heat load calculation method, in which the climate data were compressed, has been often used for evaluating annual energy consumption of heating and cooling plants. The present study discussed on estimation accuracy of five kinds of typical simplified methods; consecutive day method, monthly average method, ten days-average method, multivariate analysis method and standard deviation method, all compared with the non-simplified calculation results. The effects of unsteady calculation and steady calculation were also discussed. Three kinds of typical district heating/cooling plants, all electric system, all gas system and combined system of them, were considered to evaluate the calculation methods taking an urban area as an example, where office buildings, commercial buildings and residential buildings are included. After the heat load was calculated by every simplified method, annual primary energy consumption and the COPs of those systems were estimated using system simulation technique. The Micro HASP was used to calculate instationary heating and cooling load. All the simplified methods had almost the same order of accuracy with about three percent of errors in every consumption, if only the instationary calculation was used. While the steady state calculation using the simplified methods resulted in large errors in the heating loads of the residential building and commercial building, in which the stored heat in the building masses due to intermittent heating were underestimated. It was concluded that the simplified calculation methods are available for evaluating the performance of the heating/cooling plants if only applying unsteady heat load calculation.

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Mixing characteristics in the hot water storage tank caused by supplying cold water were obtained and the method to predict t_0 (the switch over time to the process of extruding hot water) and H_0 (the height of the mixing region) was shown in previous paper. Still it is considered to be necessary to predict temperature distributions and their changes in a hot water tank for the design of a storage water heater. Temperature distribution changes in the rectangular hot water tank caused by supplying cold water has been measured. From the consideration of experimental results, the mixing region structure model has been proposed. The model consists of the idea that the mixing region is divided into two layers (mixing region I and II) and they change over three periods (forming, growing and developing periods). Before t_0, the whole mixing region is considered to be the mixing region II and the mixing region I is slightly formed in the bottom of the tank at t_0. The forming period ends at t_0. The temperature gradient at the mixing region II gets great and the mixing region I grows in the growing period. The growing period ends at the time the temperature gradient reaches maximum. In the developing period, the mixing region II doesn't change and the mixing region I increases it's height at the mean velocity in the horizontal cross section of the hot water tank. The method to predict temperature distribution has been shown. Fairy good agreements have been obtained between experimental and calculated results. It has turned out to be possible to predict temperature distribution in a hot water tank caused by supplying cold water with comparatively high accuracy.

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When a utilities underground conduit is ventilated, the conduit body serves as an air duct, and is directly installed to the air inlet and outlet. Under this condition, it is necessary to provide the conduit with an air volume damper. In this paper, the authors propose a partition type damper as this utilities, and have the theoretical consideration that the pressure loss of this damper installed in the circular duct is caused by the contraction and expansion of air flow. Theoretically, the ratio of the contracted air flow area (A_c/A_o) is computed by applying the coefficient of contraction using two dimensional model analysis to the existing partition section. Therefore, the computed coefficient of pressure loss of this damper can be in good agreement with the experimental value by making a few corrections. Also, the pressure loss of this damper can be expressed in terms of the following equations; dP_d=1.15(A_o/A_c-1)^2P_v where, dP_d: pressure loss of partition type damper [mmH_2O] P_v: kinematic pressure in air duct [mmH_2O] A_c/A_o=0.275C_r^2-1.275C_r+1 C_r: ratio of the length of partition to the diameter in center of air duct The experimental range is; 0.245≦C_r≦0.438 2.21mmH_2O≦ P_v≦26.78mmH_2O 5.9×10^4<Re<20.7×10^4

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In order to use SET^* as a thermal index for 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 paper (Part 1), the regression line between SET^* and the whole body thermal sensation was shown as a result of the winter subjective experiment, and then the sexual difference of the regression line and SET^* at neutral thermal sensation calculated from the regression line were examined. This paper (Part 2) discusses the seasonal difference in a correlation between SET^* and thermal sensation by comparing the results of the above winter subjective experiment and similar summer subjective experiment. The main results in the winter and summer experiments are shown as follows. 1) The seasonal difference was not found in the regression lines between SET^* and the whole body thermal sensation. 2) In both winter and summer seasons, the sexual difference was not found in those regression lines. 3) The zone of thermal neutrality for Japanese in which thermal sensation votes were from 4: slightly cool to 6: slightly warm was around 22〜26℃ SET^* through winter and summer seasons. 4) The seasonal difference in a percentage change of thermally neutral votes from subjects was small, and a SET^* range which gave more than 80% thermally neutral votes coincided with the zone of thermal neutrality, which was around 22〜26℃ SET^* as described above.

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