The planning of living spaces under conditions of non-uniform thermal radiant fields requires a detailed analysis of radiative heat transfer to each part of the human body. However, at the same time, it is necessary to evaluate the characteristics of the thermal radiation environment for the entire space. This evaluation requires the computation of heat transfer to the entire body to provide an accurate distribution. Thus, an analysis method that is not computationally demanding has to be developed. The parallel projected area factor has been used as an analysis method of the angle factor between the whole human body and the surrounding walls. Compared with direct calculations of the angle factor of the differential areas of the body surface, this method significantly reduces computational effort. In this study, this method based on the projected area factor is extended to each part of the body by subdividing the whole body into 17 parts. This extension provides the evaluation of each part of the human body at a reduced computational load. However, this method needs a large number of photographs to develop a database of the projected area factors, and the angle factor may not be sufficiently accurate when the distance between the body and a wall is very small when the angle factor is calculated for the whole human body at once. In the present work, the databases are quickly developed using a 3D model of the human body. Moreover, it is confirmed that this subdividing method can be applied to closely located walls, for e.g., 0.5 m apart.

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In order to treat sewage, it is required to estimate sewage temperature and sewage flow rate near domestic and industrial the buildings. In this study, we measured the sewage temperature and flow rate in a sewer line to characterize the characteristics of sewage. 1) We measured the sewage temperature and flow rate at 17 at locations in t three different sewage-treatment in Osaka City. 2) In catchment areas corresponding to large housing ratios, we observed that the trend of the hourly sewage flow rate and the hourly ratio of house water consumption are similar. 3) We analyzed the correlation of the monthly average sewage temperature and air temperature. As a result, the correlation of 0.9 determined from the study provided a highly accurate regression equation. 4) With respect to the intended purpose of a given building (domestic od industrial), the characteristics of sewage flow rate differ between weekdays and holidays.

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Environmental destruction and increase in fuel costs have recently been escalating rapidly. In this light, the development of a highly efficient heat exchanger is strongly needed. In this study, the falling-film-type heat exchanger that can exchange heat with high efficiency via the use of a falling film was investigated. The heat carrier flowed inside the heat-transfer pipe. In contrast, the falling film flowed outside the heat-transfer pipe, thereby exchanging heat. Subsequently, the basic heat transfer characteristics of the falling-film-type heat exchanger were clarified and design equations were derived.

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In the present study, the prediction accuracy of the license-free code OpenFOAM was evaluated analytically for the determination of the flow field, conventional heat transfer and radiation heat transfer . Although OpenFOAM predicted a larger value of turbulent viscosity than those obtained using commercial codes only in the vicinity of the system's wall, the viscosity values showed good agreement in other areas. As for convective heat transfer, the discrepancy of the predicted value of turbulent viscosity with respect to those obtained by other codes in the vicinity of wall did not appear to dominantly impact the convective heat transfer coefficient. It was found that predicted values of radiant heat transfer depended on the coordinates of the model. That is, only when the model was located at the proper coordinates could the radiant heat transfer be predicted accurately. The results indicated that OpenFOAM could be used for the accurate evaluation of indoor environments.

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