Air velocity distribution in a room is greatly affected by supply jets, that is, affected by the flow rates at supply opennings and possibly by the flow rates at exhaust openings. Air flow and contaminant distribution in several conventional flow type clean room models, in which supply or exhaust flow rates are systematically changed, are studied by means of numerical simulation based on the k-ε two equation turbulence model. The influence of the air flow rates of supply or exhaust openings on flowfields and on contaminant diffusion fields is clarified. Ventilation effectiveness of each case is also evaluated quantitatively using "Scales of Ventilation Efficiency". The flowfields in such room models as analysed here are well modeled as serial combinations of "flow units" one of which consists of one supply jet and the rising streams around it. The air flow rates of the supply outlets have influence on the sizes of flow units. At the supply outlet which has a lager air flow rate, its flow unit becomes larger propotionate to the flow rate. When the supply flow rate decrease comparing with those at the other supplies around it, the flow unit becomes small and it does not reach to the floor. The contaminant distribution is exactly affected by the size of flow units. The apparent boundaries of contaminant diffusion are observed corresponding to the boundaries of respective flow units. The change of the air flow rates of exhaust openings has inflence on the flow and diffusion fields, however, concerning the flowfield, it has rather less influence on each flow unit. However, it has great influence on diffusion field in the whole room.

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In case of activating a fancoil unit under some actual conditions utilizing a two-dimensional model room, we have investigated the fundamental characteristics of influence that air discharge direction brings on energy conservation and indoor thermal environment in both of experiments and numerical calculation. From this research, it was found that the characteristics for distribution of air temperature and movement were influenced considerably by air discharge direction and the reduction of heat loss could be possible in some cases. And also, in numerical calculation, it was confirmed that the influence of thermal radiation was remarkable and application of wall function was available for the prediction of heat loss through wall. The results of numerical calculation were in approximate agreement with those of experiments.

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The purpose of this study was to investigate the effects of acid and neutral gas adsorbents and arrangement of adsorbents in the case of composite gases. An empirical formula was established to calculate equilibrium adsorption content and adsorption band by expressing a required thickness of adsorbent with the sum of saturation and adsorption bands. The formula suggested the optimal design method for adsorber of composite odor generated from sewage treatment facilities. The formula was applied to the existing facility with inflow gas volume of 100m^3/min. to obtain concrete design factors.

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Thermal environment in an automobile cabin is both directly and indirectly effected by the outside environment which changes dynamically. The purpose of this paper is to survey and analyze the actual state of the thermal environment in an automobile cabin and driver's thermal comfort under winter conditions. For this purpose, the authors used a subcompact car with 550cc engine and the automatic transmission and Japanese healthy young subjects wearing light winter season clothing. The measuring items were: in the cabin, dry bulb and wet bulb temperatures, vertical air temperature distribution, radiant temperatures, driver's skin temperatures (Hardy-DuBois' seven points) and driver's thermal and comfort sensations; outside the cabin, air temperature, heat flux and solar energy. The main results obtained from the present study are (1) if there is an outlet of an air-conditioner at driver's feet, the air temperature at his feet is higher than those at his abdomen and head. However, the air temperature distribution becomes higher and higher towards the ceiling in case of no heating. (2) owing to the outlet of an air-conditioner, the skin surface temperature at his feet is highest, but it is lowest in case of no heating. (3) in a steady state there is a good correlation between the average skin temperature and thermal sensation in the cloudy sky or at night, but there is a little correlation between them when the sun shines.

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A series of this study describes on the reliability and maintainability of hospital facilities for a Medical School. We discussed qualitative tendencies and characteristics about the reliability in our first report. And in the second report, we reported the quantitative tendencies of maintenance. So this present report is concerned with the results of subsequent detailed research. Firstly, we clarify qualitative tendencies and The Weibull analysis results for sanitary and other facilities. With these results, we obtain peculiarities for hospital facilities. Secondly, we classify primary failure and secondary failure. Last for conclusion of this study, we refer to the relation between the extent of failure and data events.

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Many materials which consist of substances having different thermal conductivities have been used in various engineering fields. It is necessary to obtain the temperature distribution of these materials in order to study the heat transfer problems concerned with these materials. To obtain the temperature distribution, it is necessary to solve the heat conduction equation under appropriate boundary conditions. For the composite materials, however, there are a little cases acquired the results by analytically. When the solution can not be obtained by analytically, it is got generally by using numerical analyses. The iteration or relaxation method which based upon finite difference has the significant advantage among many numerical methods. It is a well known fact that successive over relaxation method (SOR) can be decreases the calculation number (N_c) that is the number until convergence of temperature distribution of steady state. It is common knowledge also that N_c depend upon relaxation parameter (α). On the α, however, there is little investigation on composite materials. Therefore, it is difficult to predict of α for these ones. On the other hand, to minimize of N_c may be very valuable for effective use of computer. From this standpoint, the α of SOR method for composite materials is investigated on various factor affecting to α, and optimum α(α_<opt>) which minimize the N_c is discussed. Main results obtained in this report are as follows: 1) N_c decreases less than about 1/10 compare with successive relaxation (α=1) by selecting α_<opt>. 2) α_<opt> increases with increasing mesh numbers that are parallel to heat flow. 3) On the composite materials, α_<opt> has qualitatively similar tendency to Yamauchi's value which predict to homogeneous field. But there is the difference about from 0.1 to 0.15. 4) N_<c,opt> has not large change in the range the conductivity ratio of armature to matrix less than 0.1 or greater than 10.0. 5) When α_<opt> can not predict exactly, it is safe to select the value of α from 1.7 to 1.8.

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A new control method has been developed, that allows a cooling air conditioner to operate efficiently when the outdoor air temperatures is low. So it can cool a room all year round. With conventional control methods, the compressor uses the same amount of electric power when the outdoor air temperature is low as when it is high, because the condensing pressure is kept higher than a predetermined pressure by the condensing pressure regulator. The new system uses a larger capacity expansion valve, a compressor with a lower minimum compression ratio of delivery pressure to suction pressure, and a condensing pressure control valve for setting the desired pressure. These improvements incresae the air conditioner's performance in low outdoor air temperature conditions, because it operates in a low condensing pressure state while maintaining evaporating pressure and the refrigerant flow when the expansion valve capacity increases and the allowable minimum compression ratio becomes low. The condensing pressure control valve can set the condensing pressure as low as possible. It can control the degree of superheat even when the expansion valve is fully opened but the refrigerant flow is small and the degree of superheat is high. It is also effective when the ratio of delivery pressure to suction pressure is below the allowable minimum compression ratio. Thus, condensing pressure is set to the minimum necessary pressure. The cooling capacity increases and power consumption decreases at a given compressor operation frequency when the outdoor air temperature is low. Thus, it can operate with a large coefficient of performance (COP) at low outdoor air temperatures. The COP of the new control method at 32Hz is about twice that of the conventional control method when the outdoor air temperature is 15℃ or less. The electric power consumption of an air conditioner controlled by this new method in Tokyo is 12% less over one year.

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