The purpose of this paper is to develope the analytical method for various types of cooling coils and to present useful charts for cooling coil design or analysis. At first, we developed the analytical method for various types of cooling coils, i.e. half, double and triple flow type cooling coils, based on the method for single flow type cooling coils. And we made it possible to calculate water flow rate in coils on the given conditions of inlet and outlet water temperatures, as well as to calculate outlet water temperature on the given condition of water flow rate. In the next stage, we proposed a new design method of cooling coils using MTD-SHF charts which is made through accurate computer simulation, and on the other hand, we showed an example as a graphical analysis of annual thermal characteristics of cooling coils, using the chart prepared for performance analysis.

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This paper presents a result of numerical analysis for laminar natural convective heat transfer in a porous homogeneous medium inside a rectangular cavity with two uniformly heated hot walls vertically and two horizontal surfaces bounded as follows, 1) Model I: the open upper surface is permeable and cooled with constant heat transfer coefficient, while the closed bottom surface is non-permeable and insulated, 2) Model II: the closed upper surface is non-permeable and cooled with constant heat transfer coefficient, while the open bottom surface is permeable and insulated. A set of the partial differential equations (mass continuty equation, momentum equation of Darcy's flow, energy equation and fluid density equation) describing this cavity model in two dimensional laminar constant properties flow field is transformed into a set of non-dimensional equations using the appropriate parameters and then approximated into the two finite difference equations of non-dimensional temperature θ and stream function Ψ by the central finite-difference in the main. These F.D. equations of θ and Ψ are solved using the successive over-relaxation method at first θ and succeed to Ψ on the boundary conditions of the cavity Model I or II in the range of Rayleigh number Ra from 1.0 to 300 and aspect ratio A from 0.25 to 4, respectively. The caluculated results are presented in the terms non-dimensional stream function Ψ, temperature θ, velocity U, velocity V and the Nusselt number for Model I and Model II. Therefore, some characteristics of natural convective heat transfer and flow field inside the porous cavity are revealed and correlations of average heat transfer coefficient depended on Ra and aspect ratio A are obtained as follows, Model I for conductive region, Nu_m=0.415A^<-1.0>(1<Ra<20,0.25≦A≦4,H_L=1) for convective region, Nu_m=0.925×10^<-3>Ra^<1.7>A^<-1.0>(25<Ra<300,1≦A≦4,H_L=1) Model II for conductive region, Nu_m=0.415A^<-1.0>(1<Ra<20,0.25≦A≦4) These results of this study are available to understanding of the local and total heat transfer behavior and flow mechanism inside the porous cavity which is assumed as a heat storage tank for air conditioning use.

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A system simulation program of the solar system which used CPC combined with dual effect absorption refrigerating machine has been developed, the system model of which is actually installed in a hospital. The characteristics of the solar plant and the optimum working condition have been discussed. Thermal capacity of collectors and working fluids were taken into account in order to increase accuracy of system simulation. Two kinds of performance index were defined for optimal control. One is the primary energy consumption of pumps and auxiliary heat source/sink, and the other is the COP of the system based on the primary energy. Using each of them and several constraints given by the design policies as well as capacities of machines, the optimum selection of the solar load and the optimum flow rate of working fluids were decided. As the result of simulations, it is suggested that the primary energy comsumption decreased by 20% in a peak load day (both summer and winter) due to the optimal control. In addition, solar energy utilization pattern was shown through yearly simulations.

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The thermal stratification process in a rectangular thermal storage tank was investigated experimentally for the case in which hot water was discharged through a rectangular duct into the tank filled with cold water. Experimental parameters varied included the width of duct, the length of tank, the temperature difference between hot and cold water and the flow rate of liquid. It was found that the physical condition of flow pattern and temperature stratification are affected predominantly by the Archimedes number based on inflow conditions and the width of duct, but not affected appreciably by the length of tank. From the result of flow visualization, the dimensionless empirical equations suitable for predicting the shape and depth of the interface between hot and cold water, the criterion of the occurrence of shortcut flow, the depth of temperature stratification attainment and equivalent tank height of the amount of mixed cold water into hot water region were deduced.

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Long term ground heat storage tests with vertical pipes buried under a house and heat recovery tests by the natural and mechanical methods were carried out. In the natural heat recovery method without using a heat pump, heat storage was started in August and ended in October 1981, and the house was then left in its natural condition without heating. The indoor temperature remained above 6℃ even in mid February, and the indoor/outdoor temperature differentials amounted to 13℃, which suggested the effect of the heat storage. With the mechanical heat recovery method using a heat pump, the heat is stored starting in September and ending in October 1982. From early December, the heat pump was operated for heating to maintain room temperature at 20℃. The amount of heat extracted from the soil was larger than that of the heat stored, demonstrating the effects of the mechanical heat recovery. However, as a heat restoration from the house to the soil was observed, thourough insulation is inevitably needed for the house with the heat storage system installed under the floor directly.

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An indoor temperature, a soil temperature, a heat storage rate and a heat recovery rate with long term ground storage under a test house were calculated. In case of the natural heat recovery method, the minimum indoor temperature at the test house dropped to 0℃ in the coldest season in Sapporo. The effect of the long term heat storage on the indoor temperature rise was not sufficient. In the mechanical heat recovery method using a heat pump, the amount of heat extracted from the soil was larger than that of the heat stored. This was caused by the heat recirculation between the house and the soil and the direct heat gain which could extract from the soil using the heat pump without the heat storage. The heat recovery rate was about 0.97 when the insulation at the ground surface was installed. It was found that the high level insulation between the house and the soil is necessary.

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Kita Ward Office Building was designed as an energy-efficient model building of Nagoya City. It was decided by the city government to investigate the actual performance from the viewpoint of energy as well as environment in order to feed-back the knowledge to the future design policies. Present paper introduces the building design at first, both architectural and mechanical, as well as energy conservation technologies applied. It also includes facts how the measures and analyses were made applying the additional installation of sensors and data aquisition center. Latter half of it is devoted to develop the analyses of actual performance of principal energy-efficient equipments, that is gas-fired double-effect absorption machine, variable volume pump/fan systems and total heat exchangers between outside air and exhaust air. Results show that the performance of variable volume system saved fan and pump energy by approximately 35% in the winter, and the total heat exchangers had almost the same efficiency as the manufacturer's catalogue data, but the COP of the absorption machine has been a little lower than the predicted value from the factory test.

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Energy Conservation Law in Japan provided a measure to predict the energy consumption performance of an air-conditioning system using the index CEC, coefficient of energy conservation. CEC, however, can not actually be gained through measurement directly in spite of the importance of the comparison between the predicted value and the actual value in order to establish the true energy conservation technologies. Present report, putting the above-mentioned matters in mind, investigates the actual performance of the outside air intake control as one of the most important energy-efficient measures firstly, then calculates the most likely coefficient of energy consumption based on the heating and cooling output of the heat source, that is, a gas-fired machine. State variables and actual air-conditioning load were also visualized in figures beforehand, and total energy consumption for two years was figured out, too, showing that the Kita Ward Office Building of Nagoya City consumed energy sufficiently less compared to ordinal office buildings. The analyses showed that the outside air load reduced to about 8.4% of the estimated case without CO_2 control and total heat exchanger, and that the estimated value of CEC, 1.15, based on the actual value of the coefficient of energy consumption is almost the same as both calculated value by two kinds of system simulation programs and the predicted value before construction.

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Three new scales for ventilation efficiency and their distributions in a room are defined in order to evaluate the distribution of 'Ventilation Efficiency' in a room. They are defined according to the distribution of contaminant in a room. (1) SVE 1 (Scale for Ventilation Efficiency 1): a space averaged value of concentration of contaminant in a room; its value is defined at the point where the contaminant is generated as a point source. (2) SVE 2: an average diffusion radius of contaminant dispersion in a room; it is also defined at the point where the contaminant is generated. (3) SVE 3: a concentration value of each point in a room, where contaminant is uniformally generated in the whole space of the room. The distribution of SVE 1 and SVE 2 are calculated by scaning the source point of contaminant in whole space of the room. SVE 1 directly evaluates the exhausting efficiency of contaminant. SVE 2 evaluates the diffusivity of contaminant in a room. SVE 3 is corresponding to the traveling time of air from the supply outlet to each point. These new scales of ventilation efficiency can be calculated by the contaminant distribution which is measured by experiment, of course. However 3-dimensional simulation for turbulent flow and that of turbulent scalar diffusion by means of k-ε two equation turbulence model makes it possible to predict the contaminant diffusion sufficiently in practical application. Thus in this paper these new scales for ventilation efficiency are calculated from the contaminant distribution obtained by 3-dimensional simulation for scalar diffusion using k-ε two equation turbulence model. In order to estimate the utility of these new scales for ventilation efficiency, the characteristics of ventilation efficiency in the conventional flow type clean room are analyzed using of these new scales. The results are as follows. (1) First and second new scales well represent the difference of ventilation efficiency which is caused by changing the numbers of the exhaust inlets and the supply outlets in the same room. (2) These new scales well represent the influence of posision of the contaminant source on the cleanliness of the room air. (3) The third new scale well represents the traveling time of clean air from the supply outlet. And it is easy to know where is far from and close to the supply outlet in a view point of the air flow route. Thus it is confirmed that these new scales for ventilation efficiency are useful for evaluating the distribution of ventilation efficiency in a room.

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The purpose of this study is to introduce the equations to estimate the water demand in the various buildings. This paper describes on department stores and supermarkets as the third installment of this series. The contents are as follows. We executed the investigations of water uses in department stores and supermarkets being in the major 8 cities of Japan in the same way as the previous papers. On these results, we clarified the properties of building and equipment, the conditions of water demand and the water conservation and the opinions for water uses of persons who take charge of building maintenance. After analysing these factors related to the water demand, we introduced the multidimensional equations to estimate the water demand per unit floor area and per unit employee using the multiple regression analysis.

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