Distribution of velocity, temperature and humidity within a gymnasium were investigated by CFD prediction together with an multizone air-flow model, the COMIS. Based on the results of these analyses, the ventilation method to prevent the condensation in the vicinity of the ceiling was examined. Furthermore, the vapor source that caused condensation was investigeted by the CFD, and the rate of vapor generation was evaluated from the comparison between the CFD analysis and the measurement. Lastly, the mechanism of the high humidity formation in the vicinity of the ceiling confirmed by field measurement was clarified.

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We have carried out LCI (Life Cycle Inventory) analysis to quantify environmental burdens associated with three regional disposal systems of municipal solid waste (MSW) for evaluating the reduction effect of the system. Nine model cities were presented and the following three options were chosen; 1) individual disposal system in each city, 2) one unified disposal system of four cities and 3) that of all cities. The life cycle stages under consideration were waste generation, collection and transport, waste processing, and final disposal. The life cycle energy consumption and emissions of CO_2, NOx and SOx were presented throughout the stages consisting of use and construction (of collection vehicles, facilities, landfill sites, etc.) processes. We found that the MSW disposal system with power generation in a larger designed area reduced the associated energy and environmental burdens per waste, compared with the individual disposal system.

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New type of storage electric water heater has been developing these a few years, which supplies hot water through the heat exchanger located in a vacuumed steam space. On this type of water heater, it is strongly expected to reduce the big noise occurred when the boiler water is low temperature. Therefore, the occurring mechanism of boiling noise was made clear and one efficient method of noise reduction was reported in our last paper. In this paper, a noise reducing method, which is efficient to make the collapsing pressure of bubbles quite small by keeping the vapor bubbles minute, has been employed. The concrete method to make the vapor bubbles minute is to attach a covering piece with semi-closed spiral channel on a heat transfer surface. The design methodology of the above formed heat transfer surface and the validity of proposed noise reducing method were discussed. By many experimental results, it was confirmed that the spatial density and generating rate of vapor bubbles were increased by keeping the small vapor bubbles in the semi-closed channel as the forming nuclear, and that the collapsing pressure was violently decreased as the vapor bubbles were decoupled from the heat transfer surface and condensed with keeping their shape small. Because the impulse pressure occurred at the collapse was made quite small, the validity of the proposed method in this paper was confirmed by the result of noise reduction 20dB.

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An effective heat exchanger in the dropwise condensation is hoped to be developed for the saving of resource. However, the heat transfer characteristic is influenced by many factors, and their relations have not been clarified yet. In this research, the drop diameter, the cleaning frequency of falling drops on an inclined plate and the dropwise condensation heat transfer characteristic under steam pulse jets have been experimentally investigated. As a result, empirical formulas concerning the vapour flow rate, the diameter, the cleaning frequency of falling drops, and the dropwise condensation heat transfer in each jet condition had been obtained for each inclination heating surface. Moreover, relationship between the effect of cleaning frequency and diameter of falling drops on the heat transfer was become clear.

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As a proportion of the fan power input occupied in the total energy consumption is significant, it becomes important to save air conveyance consumption recently in order to conserve air conditioning energy along with a reduction in the building air conditioning load. In the previous reports, some different effects of energy saving between some different kinds of VAV control and fan control systems are introduced. In this report, we measured the air conditioning energy consumption saved with the VAV systems being controlled by adapting air supply volume measurement of each VAV and compared this system with the static pressure control system of air supply duct. As a result of these studies, the following was found; Along with the reduction of air supply volume, the energy saving effect is upgraded when compared to the static pressure control system of air supply duct. For example, as the air supply volume reduces to about 30%, the fan power input being controlled by this system counts for about 45% when compared to the static pressure control system of air supply duct. According to the results of the theoretical calculation of fan rotation and static pressure, the reduction of the fan rotation and static pressure indicates an approximate value equal to the results of actual measurements. Because of the operation performed with low air volume for many hours, this VAV system was proved to be effective.

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How the material flow of municipal waste can be controled was investigated from the waste composition and questionaire (Parts 1 and 2). It is essential to grasp the environmental loads from each key waste treatment process in order to evaluate the effect of whole waste management systems from separate collection to waste treatment, landfill dumping. For the main processes of waste disposal, waste collection, incineration and landfill, the LCI data for several targets were specified, compared with each other, and then analysed from several viewpoints. Such results were obtained, that waste collection efficiency can be increased, that desulfurizing process and power generation play major roles for CO_2 emission from incineration sites, and that liner and soil stabilization are the basic components of landfill site construction. As a result, specific environmental loads for each process were obtained in this paper.

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For the designing data of a hybrid air-conditioning system utilizing natural and mechanical ventilation, the characteristics of the indoor thermal environment are examined with CFD (Computational Fluid Dynamics) simulation under the various conditions of mechanical air-conditioning system, indoor heat generation rates and the width of office room. Also, cooling load of the mechanical air-conditioning system to maintain the task zone at the target temperature (26℃) is analyzed based on the results of these simulations. Floor supply ceiling return air-conditioning system is energy conservative as it cools the task zone effectively. Cooling load of mechanical air-conditioning system is increased as heat generation rates and the office width are increased. By the effective heat exhaust at the outflow window opening, however, its increasing rates is smaller than the conditions under the perfect mixing assumption cases. From the results of case studies, a simple cooling load model implying energy conservation effect of hybrid air-conditioning system was proposed. The point of this cooling load model is that the temperature stratification in a room is considered in building energy simulation (net work. simulation) for long term. With the model, energy simulation for the office building of 25 stories was conducted. The results show that energy conservation rate of 16% is achieved.

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Since the thermal environment in a vehicle compartment is not uniform, the thermal sensation differs locally. Then for the improvement of air-conditioning property in the vehicle compartment, the evaluation method of local comfort is required, which has not been established yet. The purpose of this research is to develop the "dispersed two-node model" to predict regional skin temperature. The new model is derived based on the two-node model and intended to have following features; 1) Calculates heat balance at each part with two-node model. 2) Core temperature, which is assumed to correspond to arterial blood temperature, is common to each part. 3) The effect of heat entrainment by the circulation of blood is taken into consideration. 4) Skin temperature is distributed locally. 5) The property of the temperature regulation is based on the detailed model. 6) An adequate heat conductance for the regional compartment is identified to predict skin temperature in a practical precision. To reflect above features, the heat balance equation at regional compartment of the body is derived. S_i=M-Q_<res>-W_<ex>-(Q_<ci>+Q_<wi>-Q_<si>+Q_<ei>) This equation is solved by the time marching algorithm with parameters of transient local skin temperature and core temperature. Dry heat loss from the human body to the environment is calculated at the surface of the clothing. In this paper, Q_<ci>, Q_<ri> and Q_<si> are supposed to be given experimentally or theoretically as an input condition. Remainders are calculated by the similar way as that of the two-node model. Using the above equation, transient heat storage rate of S_i is calculated. Steady state is obtained when the sum of S_i becomes zero. In this model, total thermoregulatory values are divided into regional values by distribution factors which are determined by arranging properties of detailed model. To achieve the target precision, the experiments with a few subjects on the typical summer condition in the vehicle where an air-conditioner is working are performed so that adequate heat conductance values are identified. Finally, by applying this method to the prediction of the environment where radiative heat load is uneven, it is proved this method gives practical precision.

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Based on the mixing mechanism in the TSHST (Temperature Selective Heat Storage Tank), which was obtained in previous paper, two ways of refinements on the sub-tank were made in order to improve the performance of the TSHST. The first way of refinements is to decrease the damper resistance by decreasing damper thickness and increasing outflow directions from the sub-tank to the main tank. The second way is to install the FG (Flow Guide), which restricts outflows from the sub-tank in order to control inducing surrounding low temperature waters. Under the conditions of the supplying temperatures constant and variable, experiments were conducted on the conditions corresponding to the initial stage of heat storage processes as previous paper. The heat mixed in the main-tank was calculated from the differences between temperature distributions measured and that of ideal. η was defined as a ratio of the heat mixed to that supplied. The method to evaluate the mixing conditions in the main-tank was shown by means of η. The way of decreasing damper resistance improves the temperature distributions in the sub-tank, but it does not affect η obviously. The potential of the FG for controlling mixing in the main-tank under the constant supplying temperature is considerably high. The FG increase mixing under some conditions of variable supplying temperatures, but it is effective as a whole because of its high potential for controlling mixing in the main-tank at initial stage.

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A mathematical model of the VAV air conditioning system control process is derived, considering the mutual influence of the room air temperature and supply air temperature variation. A simulation program is developed based on the model. By the numerical calculation of the temperature transient response, supposing a room and its VAV air conditioning system as an example, the adequate proportional gains of supply air temperature control and air volume control in case room air temperature set point follow up control, are analyzed, including the difference according to the number of VAV units belong to an air handling unit. The references of the proportional gains for the analysis are given by the simplified simulations of room air temperature transient response supposed as supply air temperature is constant, and supply air temperature transient response supposed as return air temperature is constant.

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This study aims to develop the high-accuracy analysis method of radiative heat transfer that can be used for the coupled simulation of convection and radiation. The method is demonstrated by applying it to the thermal environment around a human body with a realistic shape and size. In this paper, the method to calculate radiative exchange coefficients (configuration factors or direct interchange areas) using the Monte Carlo method was reported for the case with highly complicated geometries. Accurate radiative exchange coefficients are obtained by conducting the symmetrization procedure that forces the radiative exchange coefficients to comply both with summation and reciprocity laws. The method to compress the capacity storing the direct interchange areas was proposed by grouping some solid surface elements into one segment This is crucial when radiative heat transfer calculation should be carried out for the case with very large number of solid surface elements. A naked human body model was created in a standing posture with a realistic shape and size. The method to transfer the radiative exchange factors defined in a black enclosure to those in a gray enclosure was also briefly introduced Evaluation of geometric characteristics of the human body model and the thermal environment around the human body by a coupled analysis of convection and radiation will be reported in Part 2. Evaluation of accuracy of the method will be reported by comparing the experimental results using a thermal manikin in Part 3.

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Optimization for a certain building construction project is to find a solution with good balance between individual functional levels based on the design concept that meets client's needs including limited budget. However, due to complex relationship between individual design parameters, finding a balance point is a very difficult task. In this paper, an optimization technique considering the layered structure of design process is proposed to deal with such complex decision-making process in a rational way. In addition, taking indoor thermal environment in winter as an example, a demonstration of the proposed method is made. In the process of seeking for the optimum solution, the contribution ratio index is utilized to reduce calculation work of CFD analysis for estimation of air temperature distributions.

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