A numerical calculation model to simulate the moisture absorption/desorption characteristics of papers is proposed, of which target is to contribute to the accurate prediction for the indoor hygrothermal environment. A field survey concerning quantities and existing status of various papers in office spaces and a library leads to adopt the control volume method for an assumed one-dimensional wall as a fundamental theory. In that method κ, ν and λ' are variably regarded, but also an influence of the latent heat term on the thermal transfer equation is completely treated. Hygroscopic properties of κ, ν and λ' are experimentally determined, just because those functions vs. temperature and absolute humidity within the papers are requisite in the proposed model. Finally, the simulation models on both a bunch of papers on an office desk and books in a shelf are obtained.

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Mean skin temperature and skin wettedness are widely used as parameters in good relation to man's thermal sensation. It is said that mean skin temperature is closely related to the heat stress, and that skin wettedness is to the thermoregulatory strain. In the present research, the authors paid attention to mean skin temperature and skin wettedness when man felt constant thermal sensation and reanalyzed the results of 21 experiments in which 4 young naked male subjects under sitting-reading felt "equal warm sensation". All of these experiments were conducted in a still-air test chamber. From the characteristic change of mean skin temperature, skin wettedness and evaporation heat loss and development of formulae, the following concussions were obtained. 1. The observed and calculated differential coefficient of equal "warm" sensation line on the psychrometric chart shows all minus. The values indicate larger in the higher humidity environment and smaller in the lower humidity environment. 2. The effect of humidity on thermal sensation is larger under the higher humidity environment and it decreases with the shift to the lower humidity environment. 3. Under the environments where man feels an equal warm sensation, mean skin temperature and skin wettedness don't hold constant value but varied with the environmental conditions. The effect of wettedness on thermal sensation is larger under the higher humidity environment and less under the lower humidity environment. As the results, when man feels an equal thermal sensation, the change of mean skin temperature is larger under the conditions with larger skin wettedness i.e. under higher humidity conditions and is smaller under conditions with smaller skin wettedness i.e. under lower humidity conditions 4. In warm or hot environments, the locus of equal thermal sensation lines are close to constant skin wettedness lines under the high humidity environments and are close to constant mean skin temperature lines under low humidity environments. 5. (S)ET^* calculated actually evaluated the effect of humidity excessively.

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The ice/water mixture transportation system is a very effective solution for energy saving of pumping power and cost saving of piping size. In this report, the closed sub-thermal storage tank for chilled water extracting from ice/water piping was proposed and experimentally evaluated. Simultaneously, the measurement of ice proportion in the tank using conductivity ratio was evaluated for the optimal operation. As the results, ice storage performance was practical at the condition of the inlet water velocity less than 2m/sec. The maximum IPF was over 40%. The ice proportion in the tank was measured quite accurately on the ice storage process, however, the large error was observed on the melting process.

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In recent years, the technique of measuring velocity, temperature and pollutant concentration which constitutes indoor air condition has been simplified and quickened by the use of computer. Especially for velocity measurement, PIV technique has been proposed to improve the density of observed data. However the problems of errors included in data derived from measurement systems and artificial factors, and the problems of data omission especially in PIV technique still exit. Therefore it is hard to grasp whole room condition quantitatively with sufficient accuracy. On the other hand, various methods which attempt to reduce errors and supplement data to data omission points by applying governing equations have been proposed. In this paper, we classify and systematize these methods according to the types of observations and equations used. Subsequently, we propose GCFM (Generalized Cost Function Method) which reflects the observation data of velocity, temperature and mass concentration to the mutual estimation of each field by using the cost function defined by the summation of the residuals of governing equations and data corrections. Finally we execute a numerical experiment for 2-dimentional steady non-isothermal flow field which contains pollutant emission sources to verify the effectiveness of GCFM, and we can confirm that our method is effective in the grasping of the flow fields.

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The percentage of sensible heat to the total heat charged in the spherical ice storage capsule exceeds 20% depending on charging and discharging conditions. It is necessary to consider the change of sensible heat of water and ice to predict charging and discharging characteristics of the spherical ice storage capsule with high accuracy. In this paper, measurements of the temperature distributions of the water inside of the spherical capsule were conducted by changing heating and cooling rates. The flow of the water inside of the spherical capsule changes its direction at the water mean temperature around 4℃. Heat transfer continues even though the flow in the spherical capsule stops. The experimental equation concerning the heat transfer rates inside of the spherical capsule was obtained. The simple method to calculate the heat flow rate in an unsteady-state heat conduction of a spherical body was shown to estimate the change of sensible heat of the ice inside of the spherical ice storage capsule. Finally, considering sensible heat of water and ice, the method to calculate charging and discharging characteristics of the spherical ice storage capsule was shown and the calculated results were examined.

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The liquid structure of water can be changed and is generated a single molecule water by adding 1,4-dioxane into water. In order to clarify a possibility of increasing the water-solubility of LiBr, the effect of controlling a liquid structure of water on dehydration energy of LiBr・2H_2O were examined using the differential calorie analysis in the work. Measurements were carried out over the range of 18.8〜27.9mol/kg (62〜70wt%) in LiBr-concentration and 0.92〜0.95 in mole fraction taking water as the first component. The following results were obtained: 1) Adding 1,4-dioxane into LiBr saturated aqueous solution is effective for increasing the water-solubility of LiBr. 2) Dehydration energy of LiBr・2H_2O can be decreased to 16kJ/H2O-mol, which is about less half than without adding 1,4-dioxane. 3) The information about the liquid structure of water in the solution by 1,4-dioxane adding method was reconfirmed through its application to LiBr saturated aqueous solution.

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In this paper, the characteristics of direct heat and mass transfer between the slush ice and the air has been investigated. The slush ice made by ice making machinery was stored in the ice storage tank. A vertical hole through the slush ice pile was opened for the airflow. The air was contacted directly with the ice surface to be cooled by the ice. Both effects of the cooling and dehumidification were examined by the measurement of temperature and humidity at the entrance and exit of this heat storage cooling system. Experimental results showed that the cooling effect was the higher during the operational initial stage, but it became lower with progress of time and approached to stable value until the ice was disappeared, and there was the good correlation between cooling effect and that of dehumidification. The heat transfer coefficients were calculated by dividing into horizontal direction and vertical hole plane of the slush ice pile. It appeared that the airflow rate, diameter of the hole, temperature of inlet air and initial height of the slush ice pile affected on these heat transfer coefficients. Consequently, a good correlation between the Nusselt number and the Reynolds number in the hole of slush ice pile was obtained.

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Recent improvements in the hardware performance of telecommunication machines have allowed higher air temperature atmosphere. However, workers for maintenance must feel thermal discomfort under such a moderate heat stress. To alleviate it, new two types of cooling vests, "Cotton" and "Mesh", were designed and proposed in this paper. Subjective experiments were conducted to evaluate the effect of proposed cooling vests. Four college-age male subjects and four middle-age male subjects were participated in the wear trial test. The chamber was conditioned at operative temperature of 30.2℃, relative humidity of 39%RH, and still air. By wearing new developed cooling vests, comfort sensations were closer to the neutral conditions. From comfort sensation votes it was estimated to be equal to about 1.5℃ decrement of operative temperature. Among college-age-subjects there were no significant difference in thermal sensations, but among middle-age-subjects there were the cooling effects of about 2℃ decrement of operative temperature for forty minutes. By wearing our cooling vests, the relative humidity under clothing was decreased and the sweating sensation value with the cooling vest was smaller than Control condition. The evaporative heat loss from skin with our cooling vests was about 53.5W/m^2. This value was smaller than Control condition of 68.3W/m^2.

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This paper has dealt with direct contact heat and mass transfer characteristics of air bubbles in a hot water layer. The experiments were carried out by bubbling air in the hot water layer under some experimental conditions of air flow rate, inlet air temperature and humidity as a dispersion fluid, and hot water temperature and hot water layer depth as a continuous fluid. Heat transfer and evaporation of water vapor from hot water to air bubbles occurred during air bubbles ascending into the hot water. Air bubble flow patterns were classified into three regions of independent air bubble flow, transition and air bubble combination growth. Non-dimensional Correlation equations of direct contact heat and mass transfer between air bubbles and hot water were derived by some non-dimensional parameters for three regions of bubble flow pattern.

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In a tower-style thermal storage tank, when warm water is stored in the upper section and ice with a high thermal density is simultaneously stored in the lower section, a loss of thermal storage efficiency attributable to a density inversion triggered by water of 4℃ must be restrained because such density inversion disturbs the thermal stratification. As a solution, a density stabilizing unit, called the "Duo Stable", which has a trap shape, has been newly created and installed in the middle of the storage tank in order to stabilize water at 4℃. Extensive investigation has been carried out through experimental results and numerical analyses so as to identify how shapes of the Duo Stable effect thermal stratification. In the experiment, the changes in temperatures within the tank have been measured over the passage of time with different shapes of the Duo Stable in order to identify the optimum shape. The numerical analysis was compared with the experimental result by measuring the in-tank temperatures in the steady state. As a result, it was proven that a mixture of warm water and iced water due to an inversion density could be minimized by optimizing the shape of the Duo Stable.

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It is known that water mist occasionally forms near ice surface in an ice-skate arena depending on the indoor environmental conditions. The mist can causes problems such as decreased visibility during skating competitions. The objective of the present paper is to clarify the relationship between indoor air conditions and water mist formation and to provide a useful design method for preventing mist formation in an ice-skate arena. In the former section, studies concerning the indoor air conditions for preventing water mist formation near the ice surface are described. The boundary layer theory is used to determine the criteria of mist formation. The criteria can be expressed by a psychrometeric chart. In the later of this paper, the results of measurements made in both an existing ice-skate arena and Nagan Winter Olympic Memorial Arena are described. According to visual observation, water mists were formed when outdoor humidity were high. Consequently, indoor relative humidity had become high. The measured air temperatures and relative humidities prove that the proposed criteria for mist formation are usefull for designing HVAC systems in ice-skate arenas.

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