This paper presents a new local space air conditioning system where Coanda Effect of a plane jet is utilized. When the plane jet is discharged from a slot horizontally into a half-confined space opening upward and at the opposite end, the jet is forced to curve and attaches to the floor, forming a cavity space covered by the jet. Applying warm or cool jet, we can use this cavity space for air conditioned working space. When the warm plane jet is discharged, the Coanda Effect does not usually occur due to the influence of buoyancy. In previous paper, we identified the critical conditions, presented as a function of the modified Archimedes number denoted by K, in which this Coanda Effect appears. And we proved that the theoretical analyses regarding critical conditions and the temperature characteristics in the cavity were agreed quite well with model chamber tests. In this paper, we made a series of experiments by using a real size apparatus to test the feasibility of this system. First in heating, the effect of buoyancy on the Coanda Effect was examined and the air temperature in the cavity was measured. Secondly in cooling, when the cool air jet is discharged, the size of the cavity space is decreased by the effect of negative buoyancy of cool air jet. In order to get enough space for working, we identified the value of K for cooling. Thirdly we measured the air velocity in the cavity. It was around 6% of the outlet velocity. Following equation and values are recomended for practical purposes. (Δθ_i)/(Δθ_o)=n((H_s)/h)^<-1/2> Δθ_i: temperature difference between cavity and room air Δθ_o: temperature difference between outlet and room air h: thickness of slot H_s: vertical distance of slot location from floor n: coefficient which depends on heating and cooling conditions. Practical Values of K_c and n [table] ^†standing ^<††>sitting case (A): discharged air is induced from the outside of the cavity space case (B): discharged air is induced from the inside of the cavity space case (C): setting a screen (simulated working table) on the floor in the cavity space for case (A) case (D): setting a screen on the floor for case (B) where K(K_c)=Ar((H_s)/h)^<3/2> Ar: Archimedes Number

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Use of river water for the cooling water of heat pumps in district heating and cooling plants is starting in Japan from the view point of energy conservation. River water after having been used as cooling water is discharged into the river at the higher temperature by about 5℃ than the natural river water. Therefore it is very important to predict the influence of discharged warm water on river environment when we use the river water as the cooling water. The purpose of this study is to predict the influence of discharged warm water on the river environment of the Old Yodo River which flows through Osaka city and is one of the typical urban rivers in Japan. To achieve the purpose, it is essentially important to survey the present conditions of flow pattern and water quality of the Old Yodo River which includes present the Oh River, the Dojima River, the Tosabori River and the Aji River. This report describes the characteristics of flow pattern and water quality of the Old Yodo River based on the data obtained by actual surveys having been carried out in winter and in summer. The following properties became evident through the surveys, 1) The depth of water of the Old Yodo River changes with sea level in the same way over the all water system from the Kema water-gate in the upper stream to Ajigawa great bridge in the lower stream. 2) The stream in Oh River upper than Kawasaki bridge flows always towards the sea but in the region lower than the point where the Oh River and the Neya River join inverse current appears in the period of the rising tide. 3) Salt water wedge reaches the lower stream of Tenjin bridge at high tide. 4) Water temperature and water quality in the Neya River are rather different from those of the Oh River. So it is necessary to know the water temperature, water quality and flow rate of the Neya River to predict the river environment of the water system of the Old Yodo River.

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The purpose of this study is to examine the impact of storage conditions on garbage odor characteristics. Factors of storage conditions are temperature, quantity of water added to garbage and cut state of garbage. Temperatures were established at 10℃, 20℃, and 30℃, quantities of water were established at 0g, 10g, 20g, 30g and 70g, thicknesses of sample were established at 5cm, 1cm and cutting a shredded sample. The authors used a mixture of vegetables, fruit, fish and tea leaves, and measured the quantity and quality of odor emissions for 5 days. The authors put the mixed garbage in airtight glass containers and took 5l of odor gas into sampling bags by introducing outer clean air through a pump at 3l/min into the container. For the sampled odor, the authors measured odor concentration by the triangle bag test, concentration of sulfide compounds by gas chromatography and concentration of each of methylalcohol, acetic acid and ammonia by related detection tubes. In addition, the authors measured the sampled odor using both an odor sensor interlocking a semiconductor and a total hydrocarbon. The authors diluted the sampled odor with clean air to a value of 20 on the odor concentration scale. For the diluted sample, a group of 6 female students assessed the unpleasantness on a scale from 0 to 5. The results were as follows: 1) The quantity of odor emissions increases and the degree of unpleasantness is greater as the storage temperature, and quantity of water increase and the sample thickness decreases. 2) The change in storage temperature has the greatest effect in garbage odor emissions among the various storage conditions. 3) For the sensory evaluation of garbage odor, methyl mercaptan has the greatest effect in the quantity and the quality of odor emissions among odor constituents. 4) The odor sensor value is almost directly proportional to the logarithm of odor concentration for garbage odor, and so it is possible to monitor garbage odor fluctuation by the odor sensor.

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This paper has dealt with heat energy release characteristics of a fluidized bed-type cylindrical heat energy storage vessel packed with shape-stabilized latent heat paraffin pellets. This type of latent heat energy storage material consisted of normal paraffin (pentacosane C_<25>H_<52>, latent heat: 164kJ/kg, melting point of 327.2K) as a latent heat material, and polyethylene as a shape-stabilizing material. The effects of inlet cold air temperature and air flow rate, and the amount of heat energy storage paraffin pallets on the outlet air temperature from the heat energy storage vessel and the completion time of the heat energy release process were investigated. As a result, the non-dimensional correlations for the outlet air temperature from the heat energy storage vessel and the completion time of the heat energy release process were expressed in terms of non-dimensional pumping power, Stefan number and ratio of the height of the paraffin pellets layer to the diameter of the cylindrical heat energy storage vessel.

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The mechanism for composing air temperature field in a room is explained with new concepts. Here, all heat factors in an air-conditioned room are treated simply as real or virtual heat sources and sinks. The technique of numerical simulation is used to derive those new concepts. The scales for assessing the contribution of each heat source or sink to air temperature distribution in a room are defined as CRI (Contribution Ratio of Indoor climate) 1, 2, 3 and 4. CRI 1, 2 and 3 quantitatively indicate the capacity of one single heat source in a room for diffusion and how much that heat source will raise the temperature at a point in question. CRI 4 indicates the age of heat, the time scale of heat arrival at a point from one single heat source. The scales are applied to some example as illustrations.

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In most of buildings, there always exists odors caused by tobaccos, human bodies, rotten garbage, toilets, and pets. It is important to ventilate air well enough to improve such indoor air quality. In the past, the ventilation was adequately done in houses or small shops naturally or by a ventilator since there were sufficient spaces for the air flow. There was no need to have a special ventilation system like office buildings had. However, under today's energy-conservation policy on buildings which encourages an airtight and highly insulated environment, the indoor air pollution becomes a new problem. It is impossible to stop generating all the pollutant in houses. To improve the indoor air quality, it is considered to be an effective method to remove such pollutants by using cost-effective ventilation equipment or an air conditioning system. It is also recommended to use air cleaners. In this research, we made performance examination methods for small air cleaners, and evaluated their performance and determined usage. This report is focused on the performance to remove airborne particles. After several examinations of air flow rate, we found out that it is best to measure air flow rate by the orifice flow meter. We connected a duct device to the inlets of air cleaners, and measured air flow rate when the pressure in the chamber of the devices reached to the atmospheric pressure. Also, to examine the performance to remove airborne particles, we tested small air cleaners in the performance experiment room. We could evaluate their overall performance, including air flow rate and attenuation efficiency, from the time of airborne particle concentration decreased to one tenth (1/10) of its original. The results of examinations of commercially available small air cleaners tested with odor, the tobacco smoke and JIS Test Dust (No.8) fine particles in the room were as follows. The air flow rate fell to that between 1.0 and 3.0m^3/min, the collection efficiency of airborne particles showed that between 60 and 90%, and the attenuation efficiency of airborne particles between 15 and 50%. To improve the performance of removing airborne particles, increasing the air flow rate is an important factor. For example, when air flow rate was increased to 10m^3/min, all types of cleaners showed nearly 70% of the attenuation efficiency of airborne particles.

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The purpose of this study is to clarify the uses of cooking appliances and energy consumption at kitchens for business uses such as restaurants. This paper showed the results of measurements for two electrified and two gas used kitchens located in Hiroshima City. These kitchens were different in style of cooking. The measurements were carried out through five or seven days selected in each season; summer in 1995, winter in 1995, autumn in 1996 by fiscal year. The conditions of using the cooking appliances were recorded by one or two video cameras set in the kitchens. The energy consumption was measured by electric clamp meters and a gas meter. From these results, the authors analyzed the daily and hourly frequencies and duration time for uses in each cooking appliance. Working time zone was divided into two parts; preparation of cooking and busy time zone with customers. Under each part, the relationships between the frequency and duration time per hour were analyzed. As the energy consumption for electric power, this paper showed the mean values, the maximum values, the peak ratios, etc. in each appliance and as a whole in the kitchens. The electric consumption as a whole in the kitchens increased at noon and night. The consumption of the stove used as a main cooking appliance was large at the kitchens in ordinary restaurants. The hot water-heater energy consumption accounted for about fifty percent in the whole demands of a day in winter season. The relationships between the duration time and the value of consumption per hour for electric power were analyzed. The electrified kitchen was compared with the gas used kitchen, in terms of the values of primary energy consumption per unit index; the area of kitchens, the number of seats for customers and the number of cooks.

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Heat transfer characteristics from an isothermally heated L-type corner, composed of vertical and horizontal heated plates, which can be seen at a corner in a room or at the end of a heat exchanger, is obtained numerically under an unsteady condition. Initially, a plume begins to grow at the leading edge of the horizontal plate and a small vortex is generated. The vortex moves along the heated plate and is separated from the plate. This vortex affects the local heat transfer; namely, the heat transfer improvement by the sweep of the vortex and the heat transfer depression by increase of thermal boundary thickness due to the vortex separation. Ripples continue to form on the horizontal plate and travel to the vertical plate. Average Nusselt number on the L-type heated plate depends on one third power of Rayleigh number.

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In this paper, some CFD (Computational Fluid Dynamics) calculations with the standard k-ε and low-Reynolds number k-ε model for the airflow and temperature distributions have been done for the experimental atrium. The simulation basis is the simplified experimental data, which is measured without air conditioning nor ventilation, and with air cooling. The numerical results are compared with experiments, and the effects of simplifications of the boundary conditions and the simulation conditions of CFD are discussed. Also discussed are the behavior of predicted heat transfer rates in CFD models of the standard k-ε and low-Reynolds number k-ε model. As a result, the following conclusions are revealed; (1) Effective in the natural convection case is the heat gain by the steel frame which has a large surface area comparing to the total surface area of the floor and wall. (2) On the whole, simplifications of the boundary conditions sometimes give us different properties of the indoor climate from the actual situation, however, small-scale changes of the boundary conditions have little influence on the mean flow pattern and temperature distribution. (3) The use of the low-Reynolds number k-ε model gives us more precise prediction results for the temperature distribution and the convective heat transfer rates.

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