In this paper, the flow chart of design method of wind-forced ventilation is presented, and the basic investigation on the ventilation of the room with a single opening is made through experiment using a model enclosure. In conclusion, the following results are obtained. 1. The concentration of contaminants in a room under ventilation through a single opening is almost uniform except the vicinity of the opening. 2. The intermediate factor should be introduced to predict the air flow rate through opening. 3. The ventilation efficiency is in good correlation with R.M.S. of velocity fluctuation of approaching wind and air velocity in the opening.

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It is known that the cavitation in a contraction pipe occurs in two patterns, cavitation (separation cavitation) on the streamline separating from the down contraction part and cavitation (vortex cavitation) caused by the secondary vortics of the contraction part. Generally, the attention is paid only to the separation cavitation on the streamline, because the influence of the vortex cavitation on the flow is usually smaller than the separation cavitation on the streamline. In this paper, the cavitation performance of the contraction pipe was experimentally concerned. The aspects of the cavitation occurrence were observed and its critical conditions were clarified. The following conclusions are obtained. 1) It is confirmed that separation and vortex cavitations occurred in the contraction pipe. 2) Separation cavitation is easily occurred comparing with vortex cavitation. 3) When the contraction angle and the area ratio are constant, the critical cavitation number shows a constant value regardless of Reynolds number in the region of this experimental condition. 4) As the contraction angle is large or the area ratio is small, the occurrence of the cavitation is easy. 5) In the region of the area ratio S=0.2〜0.8 and the contraction angle α=45〜90°, the critical cavitation number K_d is expressed by the following correlation as a function of the contraction coefficient C_c. K_d=(1.62)/(SC_c)^2-1

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The results of experiments of the regenerators on open cycle solar absorption dehumidifying/drying system using lithium chloride (LiCl) solution as liquid desiccant are described. From the experiments conducted in August 1987, it was found that the fine mesh linen cloth was the most suitable among four different trickling surface materials for preventing channeling. Experiments on the open-end type and closed-end type of regenerator with the same trickling surface material were carried out in the same year and the extra experiments in May 1988. As a result, it was found that the regeneration performance of the closed-end type was inferior to that of the open-end type and the spring season had enough potential for regenerating LiCl solution. The fundamental characteristics of the mass transfer between the LiCl solution and the air on the trickling surface were obtained from the experimental data. The plots of the non-dimensional numbers calculated for the temperature range of LiCl solution, 30℃ to 60℃, and the concentration, 27% (weight percent) to 37%, from the experiments of May 1988, were deviated slightly from the relationships of the general equations for the laminar and turbulent forced convection mass transfer.

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The discharge characteristics of latent heat storage columns are important to design heat storage devices. Strict analysis of melting and crystallization phenomena requires complicated calculations. In this study, a simple numerical method which could be practically used with sufficient accuracy was proposed to calculate the outlet temperature of the heat transfer medium from heat storage columns. On the other hand, a trial latent heat storage column using packed paraffin wax as phase change material was made to perform experiments under various operating conditions, and experimental results were compared with results calculated by this simple numerical method. Consequently, it was recognized the outlet temperature of the heat transfer medium was predicted with this numerical method.

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In case of activating a fancoil unit as an air conditioner utilizing an actual size room, as previously reported, we have investigated the influence that the difference of air discharge direction brings to the indoor environmental factors such as air discharge and return temperature, heat loss through wall and distribution of air temperature and velocity in the experiment. Besides, these factors were compared to evaluate synthetically by means of PMV (Predicted Mean Vote) in both of air discharge directions. It was confirmed that the method of horizontal air discharge at the bottom of fancoil unit (Discharge 1) is superior to that of vertical air discharge at the top of it (Discharge 2) for energy saving and capability of lowering the air discharge temperature. It was found that the draft is avoidable to some extent in the Discharge 1 when the width of air outlet and air discharge temperature are selected appropriately for the rate of air discharge. In general, when Archimedes numbers are high comparatively, the values of temperature factor in the Discharge 1 are smaller than those in the Discharge 2 because of the occurrence of the short circuit phenomenon. However, within the lower range of Archimedes number, the values in the Discharge 1 are larger considerably than those in Discharge 2. It means that the thermal energy in the discharged air is utilized effectively for the air conditioning.

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This report describes the results of the long term investigation of the heat storage effect and the heat recovery rate by using an aquifer. The aquifer is used as the heat source to supply a great deal of hot water to boundary utility every day in winter season for physically handicapped persons. As the resuts of measurements for 7 years, the total quantity of heat extracted from the aquifer in 1989 winter, was 172Gcal and the percentage of extracted heat to injected heat was about 53%. The temperature of water changed from 43.1℃ to 36.7℃, during extraction of water when the average temperature of water injected was 46.1℃. It indicates that the seasonal heat storage in an aquifer is effective.

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One large chamber, and four box chambers were prepared to investigate the effect of the surface air velocity on Surface Emission Rate (SER) of perceived air pollutants, where four materials were tested. SER was calculated from the mean perceived air quality in decipol voted by trained panel. It was found that the greater the ratio of air change rate to loading factor, the smaller the SER of perceived air pollutants, and that the higher the surface air velocity, the greater the mass transfer coefficient and the greater the SER of perceived air pollutants.

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Heat recovery system from waste water in urban areas is considered as one of the main energy systems in sustainable society in the near future. It is important to know the actual state of the properties of waste water, such as temperature, flow-rate, etc. However there were few data with respect to the properties of the waste water discharged from an apartment house. Some field measurements of the properties of the waste water discharged from an apartment house with domestic hot water supply system were conducted. As the results, it became clear that there exists fairly high temperature water which can be used as the heat source for heat pump. Moreover, some evaluation methods of the waste water as a heat source for heat pumps are discussed. As the results, a new evaluation method, which takes temperature level and thermal capacity of the waste water and size of the thermal load into consideration, is proposed.

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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 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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There are various sources of fumes and dusts in a casting plant, and contaminants from such sources make working environment dirty as a matter of industrial hygiene. Local exhaust system or general ventilation is generally installed in the working place for the purpose of reducing contaminant. Local exhaust system is quite effective, however, there is a case when exhaust opening can not be installed closely to the contaminant source. General ventilation system, based on dilution method, is used in such a case, but this system is less effective than the local exhaust system. In this report, we studied the general ventilation of metal melting shop in an actual casting plant by numerical simulation. At first, present ventilating system to reduce concentration of fumes producing from metal smelting furnace and holding furnace was investigated, and ventilating flows were solved by numerically using k-ε turbulence model. As a result, close agreement between measured results and numerical calculations was obtained. Then, we suggested an improvement ventilation plan applied the uniform flow ventilation to reduce the exposure of workers, and estimated ventilation effect of the suggested measure by numerical simulation. As a result of numerical calculation, fume concentration at working limits or breathing limits of workers, where located under hang walls, became very low, and followings were become clear. 1) Ventilation by dilution method is not suitable for the purpose of reducing contaminant with mighty buoyancy. 2) Installing adequate hang walls is very effective to eliminate fumes with buoyancy. 3) Suitable air supply system is necessary to prevent the diffusion of fumes from high temperature sourses.

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