In the analyses of flow in piping networks, dividing and combining losses at branches are usually ignored as being minor compared to friction losses in pipes. In this report, followed by the previous one in which a basic T-type diving flow has been analysed, a basic T-type combining flow with a combining loss involved is analysed. The results obtained are, 1) The influence of the combining loss on flow distributions is considerably less than that of the dividing loss clarified by the previous report. However, the influence of the combining loss on over-all loss coefficients is as large as that for the dividing loss. 2) When a total pressure at the end of an upstreamside main pipe differs that at the end of its branch pipe, the flow distributions and over-all loss coefficients change depending on the Reynold Number of the piping system. 3) The effect of radii at the branch on the flow distributions is negligibly small, but that on the decrease of the over-all loss coefficients is appreciable.

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In order to estimate thermal environment of an underground space, it is essential to know its surrounding underground temperature. The fact that the underground temperature in an urban area is considerably higher than that in a suburban area has been observed by several workers. This phenomenon is considered as the result of urbanization, but its detail has not been clarified. The purpose of this study is to obtain the information on underground temperature in the urban area. Based on the solutions of the heat conduction equation, effects of several factors caused by urbanization on the underground temperature were discussed in this regards. The equilibrium underground temperature was defined as an index of underground temperature. It means the spatial and annually time averaged underground temperature at a certain place. Effects of several factors caused by urbanization on it were analyzed numerically. The factors considered in this study were as follows: (1) Impervious pavement on the earth surface. (2) Change of the climate in urban area (i.e. urban climate). (3) Change of radiation balance at the bottom of urban canyons. (4) Heat flow from buildings on the ground or under the ground. In this study, the simplified methods of numerical calculation for a change in the equilibrium underground temperature by these factors were suggested. In case of calculating the effect of heat flow from buildings, we need to solve the heat conduction equation at steady state numerically. However, in other cases, we can calculate it directly from the annual means of solar radiation, air temperature and long-wave radiation, and several parameters related to earth surface heat budget without solving the heat conduction equation. As the result of this analysis, it was seen that impervious pavement on the earth surface and heat flow from buildings under the ground increase the equilibrium underground temperature to a considerable degree. Especially, the effects becomes greatly at the place where the amount of solar radiation is large in case of the former, and at the cold places in case of the latter. Impervious pavement on the earth surface increase the equilibrium underground temperature to 3.6℃ in Osaka, but the amount of difference is closely related to the value of convection heat transfer coefficient. Then, more research is necessary about the convection heat transfer coefficient in order to calculate it more exactly.

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In this paper, we report the results of the experimental research for the mechanisms of aerosol deposition on semiconductor wafers in clean rooms. By the laser light visualized method, we observed the motion and deposition of particles near and on the wafers. The deposition velocities were measured using the following experimental parameters: voltage of the wafer surface, particle charge quantity, particle size, relative direction of air flow to the wafer surface. It was concluded that among a number of factors, such as inertia, gravitation and diffusion, electrostatic force had the greatest effect on the depositions of submicron or few micron diameter particles.

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The actual condition of the total building equipment was investigated in 1983. The subject of this survey was the office buildings locating in four cities (Fukuoka, Kumamoto, Kagoshima, Oita) in Kyushu. The outline of this survey and the characteristics of buildings are described in this paper. The contents are as follows. 1) The relation between the floor area and the number of occupants resulted in 0.048 persons per m^2. 2) For the air-conditioning system, many complaints were shown on the poor efficacy in heating and cooling. 3) For the plumbing equipment, the corrosion of fixture and piping was frequently complained. Comparing to other cities, the report of red water generation was remarkable in Fukuoka City.

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It is one of the greatest interest for clean room designers, how the contaminant diffuses in a clean room. Although many intensive trials or studies have been conducted by many researchers or engineers in this field, only the few informations were presented for the contamination control in a clean room. In order to design the effective contamination control, it is important to clarify the flowfield and diffusion processes in the room resulting from turbulent motions, because the movement of dispersed particles from apparatus or human bodies in a clean room may be assumed to be passive contaminant. In this paper, turbulent recirculating flows and contaminant diffusion in many types of conventional flow type clean rooms are numerically simulated three-dimensionally by means of a k-ε two-equation turbulence model. The results obtained from numerical simulation are compared with those given by model experiments concerned with velocity and diffusion field. The correspondence between simulations and experiments is fairly good. Proposed three-dimensional numerical simulation by means of a k-ε two-equation model enables the prediction of turbulent flow distribution and contaminant diffusion in a conventional flow type clean room with sufficient accuracy.

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In designing an effective contamination control in a conventional (turbulent) flow type clean room, an understanding of the flowfield itself and also how to control the resulting diffusion field of contaminant is most important. Therefore it is essential that clean room engineers and designers comprehend the entire flowfield and its diffusion field of contaminant not only qualitatively but also quantitatively. In this paper, turbulent flowfields of velocity and diffusion in several types of conventional flow type clean rooms are precisely analyzed by means of numerical simulation based on the k-ε two-equation turbulence model. And Ventilation Efficiency Scales which can express the characteristics of the diffusion pattern as a quantitative value are also adapted. The detailed analyses of contaminant diffusion by simulation make it possible to comprehend clearly the structures of velocity and diffusion fields in clean rooms. The flowfields in such rooms as analysed here are mainly characterized by the inflow jet and the rising streams around it. The combination of one jet and the rising streams around it forms a "flow unit". The total velocity field and the resulting diffusion field of contaminant in a room are well modeled as serial combinations of these "flow units".

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To extend the authors' previous experimental study on the thermal storage efficiency of the first vessel of a water tank compartmented with submerged weirs and dividers for the case of the step input of cold water, an additional experimental study was conducted on the thermal storage efficiency in the regions as far as the outlets of the second and third vessels, by measuring transient liquid temperature responses for the case in which cold water was discharged into the tank filled with hot water, under various hot-cold water temperature differences, flow rates, and tank configurations. From the experimental results and theoretical consideration, a semi-empirical equation suitable for predicting the thermal storage efficiency in the region as far as the outlet of the n-th vessel, η_<nV>, was deduced as a function of the number of vessels, n, the Archimedes number based on inflow conditions, Ar_0, the Peclet number, Pe, and three geometric parameters, φ_1, φ_2, and τ_<v1>. The applicability and usefulness of the semiempirical equation have been supported and illustrated by comparison with existing experimental results of the thermal storage efficiency obtained with a model water tank of small scale and a full-sized water tank.

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The questionnaire inquiry on building service systems and indoor environment of office buildings was conducted from 1983 through 1984 in four cities, Fukuoka, Kumamoto, Kagoshima and Oita in Kyushu district. This paper describes in particular the air-conditioning systems, equipment capacity and management beside the architectural aspects, classifying the buildings by management into three classes of public, ownership and tennant buildings. Similar surveys have been carried out in the past, but almost of them were limited to metropolises such as Tokyo, Osaka and Nagoya. Many differences are found between cities in the climate, customs, economy, social activity, etc., which give an influence in utilizing air-conditioning systems. Therefore it is of much importance to analyze the chracteristics of local cities by conducting surveys so as to summarize the general aspects over all the country. Main purpose of this paper is to examine the chracteristics of Kyushu district about air-conditioning aspects by comparing the results with those of other surveys ever reported.

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