Development of fuel cell system for houses constituted from reformer, fuel cell, auxiliary heat source by boiler and heat pump system and etc. is considered. In this paper, operation cost in consideration of the transient response characteristics of the system when giving electric power load to the fuel cell system is estimated. The transient response characteristics of electric power of the fuel cell system are investigated by the difference in the setting parameter values of proportionality-integration control parameter of system controller. Moreover, it investigates also about the transient response characteristics of electric power of the system by the difference in time constant of the fuel cell and the reformer. And in this analysis, simulation of inputting into the system controller of control parameters considered to be suitable, and system operating are carried out. The operation costs of the fuel cell system were estimated using the electric power and the heat demand model in average individual houses in Sapporo and Tokyo as an analysis example. Consequently, it is predicted by the setting value of control parameters that the difference among 10% or more arises to operation cost at least.

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When the distribution properties of the age and the residual lifetime of air are analyzed by CFD (Computational Fluid Dynamic), the analysis of the age and the residual lifetime of air to each supply opening and exhaust opening were impossible in a room with multiple supply opening and exhaust opening. Authors proposed an calculation method of Scale for Ventilation Efficiency (SVE) the 3rd (age of air) and the 6th (residual lifetime of air) based on CFD, the distribution properties of the age and the residual lifetime of air were able to be analyzed by this SVEs. However, this method doesn't make a distinction between the airs from each supply opening or exhaust opening. Therefore, it is impossible to analysis the spatial distribution of the age and residual lifetime of air corresponding to each supply opening and exhaust opening. Recently, the large number of air-conditioning system that multiple supply opening and exhaust opening exist in the room like the task ambient air-conditioning (personal air-conditioning) etc. have been proposed. Such air-conditioning system should be required for examine the distribution properties of the age and residual lifetime of air each supply opening and exhaust opening In this research, we will propose new ventilation efficiency index SVE3^* (age of air) and SVE6^* (residual lifetime of air), introduce the calculation method based on CFD. It has been confirmed that age and residual lifetime of air as obtained with respect to individual supply and exhaust openings still become identical to those generalized for total room, when such individual values are corrected for weighted averages based on the respective contribution ratios. The new methods have made it possible to evaluate easily and in more detail the effects that the supply and exhaust openings in the room.

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In order to improve COP of the air conditioner, the numerical simulation is widely used on the design of the heat exchanger, which assumes 1-dimensional flow of the refrigerant and optimizes the flow pattern of refrigerant considering the heat transfer between air and refrigerant and the total pressure drop of the refrigerant flow. The evaluation of the heat transfer on the fin surface of the heat exchanger is based upon the 1-dimensional fin efficiency model. On this study, we have adopted the 2-dimensional straight fin as a subject, and have constructed the 2-dimensional fin efficiency model by using the numerical experiment data which derived from numerically solving the heat conducting equation of the fin directly. Furthermore, regarding the heat transfer with condensation of moist air, we have proposed the conventional latent heat model which identifies the latent heat added upon the fin surface with an increase of the heat transfer coefficient, and have incorporated the model with the traditional method of calculation, which the bypass-factor of latent heat is equal to that of sensible heat, and have inspected the validity of the model. As a consequence, it was proved that this model gives good approximations in the case that the sensible heat load is low and the number of transfer unit is low. It was also found that the existence of dry area and the 2-dimensional distribution of temperature and saturate absolute humidity on the fin surface are great causes of significant errors of approximation of the mean temperature and mean saturate absolute humidity on the fin surface.

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The decrease of residual chlorine concentration in water is considered in tank receiving water and in water tank standing above. In the case of flowing into the tank, factors of residual chlorine concentration were assumed to be direct flowing in from the pipe, flowing in from the ball trap and falling on the water surface, and in the case of retention, factors were assumed to be the water temperature, the water depth and the presence or absence of the upper lid. This content was examined experimentally. As the result, the loss of residual chlorine and the extent in flowing in, and the loss of residual chlorine and the extent in retention in the water tank were uncovered. Moreover, the dissipation of the residual chlorine in the water tank could be predicted.

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