The 'thermal control wall' heat exchanger, functions as a skin wall as well as a means to vary the exterior wall thermal resistance of a building. The 'thermal control wall' consists of an interior panel, structural wall, an exterior panel and a control valve. The 'thermal control wall' can thus save energy for air-conditioning. This paper describes an evaluation of the 'thermal control wall' through simulation and outdoor test results. One type of 'thermal control wall' which has it's exterior panel installed higher than it's interior panel, has higher thermal conductivity than other types. The performance of the 'thermal control wall' is influenced by solar radiation, wind velocity, and temperature differences. This performance can be calculated using the 'thermal control wall' specifications and weather data.

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This paper presents a following day's hot and chilled water load forecasting system by using artificial neural networks. The neural network can realize the nonlinear relationship between the load and the environmental factors. Load forecasting is very important for the economic operations of air-conditioning system. Many statistical methods have been developed and used for such forecasting. It has been difficult to construct a proper functional model or needed huge efforts. We propose the optimum neural-network structure and sufficient training method in concern of learning speed and categorizing ability, under the investigation on the effective factors for the forecasting system. From the simulation experiments, we obtained the successful results comparing with conventional methods.

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The hierarchic frame network has been proposed as a new diagnostic model that can be applied to most of air conditioning systems. In the present study, stepwise diagnosis was used as an evaluation item, and the practicality and usability of the diagnostic model were verified in actual air conditioning systems. In the first diagnostic step, which detects fault symptoms, it was possible to perform fault detection without errors by considering the range of design specifications, safety device settings, and operating conditions with the setting of threshold values. In the second diagnostic step, which classifies the types of fault phenomena, it was possible, by adjusting the threshold which was based on statistical analysis of actual operating data and by setting a condition of high frequency for fault detection, to classify fault phenomena from which noise superimposed on the measurement signal had been removed. In the third diagnostic step, which performs fault localization, it was possible to identify faulty apparatus by inferring the fault phenomenon using knowledge of the frame network and rules. And in the fourth diagnostic step, it was possible to identify the cause of the fault by inferring the fault phenomenon using a fault tree for each apparatus. After confirming these diagnosis results in actual air conditioning systems and repairing the causes of faults, the diagnosis results returned to normal values, thus verifying that the identification of faults had been correctly carried out. The above verification process indicates the practicality and usability of a diagnostic model employing a hierarchic frame network.

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Many building owners having thermal storage HVAC systems are interested in operating cost savings with cheaper electric power rates. However, few owners and operators can evaluate the performance of their systems because of insufficient experiences, even though there are some ways to improve operating cost savings. In order to overcome these problems, evaluation indices which applied to some kind of systems are needed. The indices must be defined by considering the some conditions of the systems, for example, size of thermal storage tank, capacity of heat source, magnitude of load and so on. In this paper, we suggested these indices, and the applicability of them are examined by using measured data of real buildings that were installed water thermal storage tanks. As a result, the indices were shown to be effective to judge whether operating strategies of heat source was good or not for Peak-demand-shifting and Peak-demand-reducing.

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Building energy supply systems should be designed by taking account of not only operational aspects but also factors such as equipment production, maintenance, and renewal. In additon, the best combination of equipment and energy sources should be selected in consideration of total energy demands. The present study proposes a design method of building energy supply systems using an optimization method. Design model and procedure for the method are proposed, and equipment characteristics data are presented. By applying the optimal design method to a hospital, the following results have been obtained: 1) A cost/CO_2-minimum energy supply system can be chosen from several combinations of equipment and energy; 2) Energy supply systems can be compared in terms of cost and CO_2 emition; and 3) Optimal equipment numbers and capacity can be determined by considering total energy demands and whole energy supply systems.

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This paper has dealt with the thermal energy release characteristics of fine latent thermal energy storage particles encapsulated into micro-capsules in a water solution by air bubbles as heat transfer medium by means of direct contact heat exchange. The micro-capsules consisted of n-paraffin as latent heat storage material and melamine resin as capsule material. The temperature effectiveness, the amount of heat released from latent heat storage particles and completion time of latent heat release process were measured over the wide ranges of inlet air temperature, humidity and flow rate, and the amount of latent heat storage particles packed in a heat storage vessel. As a result, nondimensional correlation equations of the temperature effectiveness, enthalpy difference between inlet and outlet air, and completion time of latent heat release process had been derived in terms of some nondimensional experimental parameters.

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In the part 1, as the foundamental matter of study, we studied the appearance, growth condition, inhibition and biological activity of slime. In this study, we fixed our eyes upon piping which supplied recycling water. In the case when microbes attach in the piping, it is said that the following hazard may be caused; choking of plumbing fixture, obstacles of flow, blockade of pipeline, generation of odors and acceleration of corrosion, etc. Under the circumstance, we specially investigated the followings. That is, (1) deposit of the slime in such piping materials as carbon steel pipes for ordinary piping, unplasticized polyvinyl chloride pipes, stainless steel pipes and acrylic pipes, (2) deposit of the slime caused by both flow velocity and fineness or coarseness of surfaces of pipes, (3) mutual relation of both water quality and formation of the slime, and nature of the slime. The results of the research can be summarized as follows: 1) Compared with raw water (BOD concentration is about 10mg/l), in the case of advenced treatment, deposit of the slime becomes extremely little. 2) In inhibiting effects of the slime in both coagulating sedimentation water and sand filtrate water, differences are shown because of both material of piping and sorts of the flow velocity. The formation of the slime becomes bigger according to the following order. That is, the acrylic pipes<stainless steel pipes<the unplasticized polyvinyl chloride pipes<the carbon steel pipes for ordinary piping. 3) It was recognized that the fineness or coarseness of the surfaces of pipes gives influences except the sand filtrate water. 4) The composition of the slime was shown with molecular formula of C_9H_<15>NO_4.

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This paper is to discuss the relationship between the jet characteristic and turbulent diffusion coefficient which is a factor of Reynolds stress giving rise to vibration and noise that take place in diffuser and orifice through the theoretical analysis for the flow mechanism by means of momentum and energy theory and experiments of these pipeline components. Therefore, it has been made clear that the turbulent diffusion coefficient can be used to make a quantitative analysis on the level of these datum of pressure loss factor for the diffuser and orifice.

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In this paper, a new method is presented to access heating and cooling loads with a condition of the same thermal condition. The traditional assumption of 'perfect mixing air temperature in the room' can not be applied to analyze the heating and cooling loads of different types of systems for a room. Different types of AC (Air-conditioning) systems induce different thermal conditions such as vertical temperature distributions, radiative fields, etc. These conditions can give effects on the heating and cooling loads. The CFD technique, coupled with a radiative heat transfer simulation and AC regulation, can provide information about more realistic heating and cooling loads. In the simulation, AC outputs (e.g., inflow air temperature, inflow air volume, etc) are changed by a feedback system of AC regulation. These changes are based on the simulations with various boundary conditions to keep operative temperature of a human model at the target temperature. To demonstrate the new method, thermal environment of a semi-closed space, which is opened to an atrium, is analyzed. The heat exchange can be occurred within these two spaces by air circulation and radiation. It is clear that both convective and radiative heat exchanges give an influence on the cooling load of the semi-closed space. To predict the cooling load precisely, the amount of these exchanges have to be estimated with a certain accuracy. In this paper, two types of AC systems are compared; one is radiation panel system and the other is all-air cooling system. With the new method, the required cooling loads for the condition of the same thermal sensation are quantitatively estimated. The effects of air curtain are also studied. In this study, the best energy saving AC system for the same thermal condition is able to be chosen; the radiation panel system with air curtain is decided as the least energy use method to cool the semi-closed space.

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The purpose of this study is to understand the co-efficient of performance (COP) on the partial load of energy source equipments by the result of measurements of a middle scale office building with thermal storage tank. The result of air-conditioning load measurements indicates that the operating time at the partical load is very long. In order to reduce the energy consumption and running cost of the air-conditioning energy source systems, their systems should be selected with the hi-performance equipment not only on the peak load, but also on the partial load. This paper reports the measurement data of the COP of air source heat pump chiller-heater and gas fired absorption chiller-heater, and analyzed the relation with COP and effecting factors. This paper shows the formula of COP for the simulation, and confirms the correctness of this formula. And also this paper reports the heat loss ratio of thermal storage tank in a year.

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This study concerns about emergency ventilating operation during fire accidents in road tunnels with large cross section (115m^2) on the Second Tomei-Meishin Expressway in Japan. The movement of fire plume and smoke induced by fire accidents is simulated using three-dimensional CFD. The result shows that under high longitudinal velocity (10m/s), the evacuate environment in a large cross section tunnel (3-lane road tunnel) is safer than in the conventional 2-lane road tunnel. Result also shows that under low longitudinal velocity (2m/s), both the temperature and the concentration of smoke of thermal fume in a large cross section tunnel are lower than that in the conventional 2-lane tunnel, meaning that a better evacuate environment can be expected near the ground of a 3-lane road tunnel with large cross section.

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In the previous works, we proposed 10 indices as representative indicator for evaluating performance of district heating and cooling (DHC) system and values of each indicator were calculated for seven types of district heating and cooling system under a certain condition. Firstly in this paper, questionnaire for weighting these 10 indices are set out on professionals of DHC system. 'Economy' and 'Consumption of energy resources' are selected as most important indicators and weights for 'Efficiency of space use' and 'Impact on landscape' are small. However, there is a significant difference of weights between sectors which the replier belongs to. Using these weights and impact matrix which indicate the performances of the seven DHC systems, multicriteria analysis is examined. Concordance analysis method which Nejikamp had developed was used in this study. As a result of the analysis, in spite of high cost, ecological DHC systems which utilize waste heat from garbage incinerator, cogeneration system or heat pump with sea or river water dominate over conventional DHC systems and individual heat source system. However, preference among ecological DHC systems changes according to circumstances.

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