The practical modeling criteria are developed to simulate the air distribution of the space in which the air motion is turbulent and occupies almost all part of a room. Exact simulation of the whole area of the room air motion requires very difficult conditions from the technical point of view. The reason why the object of the practical modeling criteria is limited within the turbulent zone of a room, is mainly dependent on the above described fact. In the turbulent zone, the eddy kinematic viscosity is proportional to the product of the outlet air velocity and the scale of a room, as will be discussed in the next Part. Based upon this finding, the modeling criteria between the scale model and the prototype may be reduced to the following brief expression. 1) For the ventilated air motion, the similarity condition is the coincidence of the Archimedes number. θ_ML_M/U_<M^2>=θ_NL_N/U_<N^2> where, θ: reference temperature L: reference length U: reference air velocity subscripts M: model N: prototype Then, the similarity condition for the capacity of a heat generator Q_H is, [numerical formula] Also, the similarity condition for the thermal resistance of walls r is, r_M/r_N=U_N/U_M(1/α_Nr_N+1)-1/α_Mr_N where, α: overall heat transfer coefficient 2) For the room thermal convection, the similarity is attained automatically only if the air motion is turbulent both in the model and the prototype. The similarity conditions are, Q_<HM>/Q_<HM>=arbitrary [numerical formula] Then, [numerical formula] [numerical formula] Experiments were carried out in order to verify the practical modeling criteria. Comparisons were also made between the criteria proposed in this report and those of several authors.

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In the preceding report, the practical modeling criteria for the room air motion were introduced on the assumption that the eddy kinematic viscosity was proportional to the product of the outlet air velocity and the scale of a room. In this report, the property of eddy kinematic viscosity is examined experimentally by the measurements of turbulence in five model rooms which differ in size. The major findings are as follows. 1) The linear relation exists between the outlet air velocity and the mean velocity at each measuring station. 2) The average turbulence intensity of a room is independent of the outlet air velocity and the scale of a room. 3) The turbulence at the central area of a room, the turbulent core zone, is thought to be close to isotropic. In this area, the Eulerian correlation coefficient can be expressed in the form, R(t)=1-const. t^<2/3> and the range of F(n)∝n^<-5/3> with respect to turbulence spectrum can be recognized. 4) The average length of the mean eddy of a room is proportional to the scale of a room. 5) The relation ν_t∝UL is derived from both measurements of mean air velocities and the turbulence of a room. where, ν_t: eddy kinematic viscosity U: outlet air velocity L: scale of a room

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Presented in this report is the applications of the practical similarity criteria for the space air distribution in the cokes quenching tower and the assembly hall. In the cokes quenching tower the main purpose of the scale model experiments was to find the desirable configuration of the tower which emit the least amount of particles in the atmosphere. Therefore, an alternative similarity criteria for the particle motion in the heated air was introduced. The model experiments were composed of two parts. One was conducted to verify the usefullness of the practical similarity criteria by means of two similar models in different scale. The other was carried out in order to compare the difference of particle emmittance by five different models in configuration. In the case of an assembly hall, the field measurement and its scale model experiment were carried out. The usefullness of the practical modeling criteria was also concluded by comparison of the field measurement with its scale model experiment related to the space air distribution.

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Mixing process of a stratified-type heat storage water tank was studied with numerical simulation. The turbulent model used in this simulation is a Two-Equation-Model which is extended to non-isotropic turbulent flows due to gravitational influence. In this model Reynolds stress and turbulent heat flux are given with algebraical equations consisting of the term which includes eddy kinematic viscosity or eddy diffusivity given by usual Tow-Equation-Model and the buoyant term which is induced from the transport equations of Reynolds stress and turbulent heat flux. In experimental studies (Part 1), the measurable property of mixing process is usually the temperature distribution in the tank, while the information about the transitional change of velocity and various turbulent property distribution and the aspect of temperature diffusion on first stage etc. can be gotten in detail from numerical simulation. The results of simulation are following. 1) Flow patern in the tank changes from circulating flow covering the whole tank to the piston flow as the formation of temperature stratification. 2) When Archimedean numder is large, the temperature stratification is rapidly formed and the vertical gradient is steep, while the stratification is not formed for very small Archimedean numder. 3) In the condition of the same flow rate and temperature difference, the entrance widened laterally improves the performance of storage tank. 4) The simulation for variable input condition was also carried out. The temperature stratification is not destroyed under the condition of rapid variation and large Archimedean number.

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The global heat loss coefficients and the η_0 intercepts of seven Japanese collectors with novel structures to reduce heat losses were determined by the GIRIN procedures which were reported already elsewhere and were modified from the NBS-ASHRAE procedures, and the results were discussed from the view point of the collector heat transfer. In our procedures, collector efficiency (η) was expanded to both linear and quadratic relations such as η=η_0-AT^* and η=η_0-{A(1)+A(2)T^*}T^*, in which A and [A(1)+A(2)T^*] were physically related to the global heat loss coefficient, and T^* being defined as the dimentionless reduced temperature. The conclusions were as followings. 1) The global heat loss coefficient of each collector reflected the effects of the heat loss reducing devices. 2) The η-T^* relationships constructed under the nearly equal environmental conditions should be used for the rating of collectors, because the conditions affect significantly on the thermal characteristics to be compared. 3) The η-T^* relation constructed from the BSE-like procedures, in which the heat losses measured during nights were used, agreed saticfactorily with that obtained by the NBS-ASHRAE procedures. 4) The obtained value of coefficient A(2) was relatively small for the range of the parameter T^*(0.1<T^*<1.0), so there was no significant discrepancy between the linear fitting (η_0-AT^*) and the quadratic fitting [η_0-A(1)T^*-A(2)T^<*2>] for the confined T^* region. However, the quadratic fitting might be better than the linear fitting, since the global heat loss coefficient determined from the direct measurement of heat losses during nights depended on the temperature difference (T_m-T_a).

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This paper reports on the study of a measurement method of offensive odor in wastewater. Since the problem lies technically in the difficulty of a direct analytical measurement (no concentration) of the offensive odor, it was the purpose of this study to determine a method using the Head Space Method under the availability condition that the odor concentration of the offensive odor generated reappears on the liquid surface. The following batch examinations were conducted with, (1) synthetic odorized water [H_2S, CH_3SH, (CH_3)_2S, NH_3, (CH_3)_3N], (2) actual plant wastewater comparing the C_h concentration by the "Head Space Method" and C_g concentration by the "Free Surface Method". C_h= K_1C_L^<m_1>…(1) C_g=K_2C_L^<m_2>…(2) C_h: gas phase concentration by the Head Space Method [μl/l] C_g: gas phase concentration by the Free Surface Method [μl/l] C_L: liquid phase concentration [mg/l] The following equation can be derived from (1) and (2): C_h =K'C_g^<m'>…(3) A correlation is observed between the gas phase concentration in the Free Surface Method by gas generation C_g, and the phase concentration (C_h) in Head Spase Method. The measurement method of Head Space Method (C_h=K'C_g^<m'>) summarized by comparing the examination on synthetic odorized water and actual plant wastewater. It is further concluded that this measurement method can be practiced in the field. When gas-liquid concentration reaches its equilibrium state in head space, this concentration ratio of H_2S, CH_3SH, (CH_3)_2S and NH_3 is applied to Henry's law.

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Air-Conditioning has a grave role in maintaining a comfortable as well as hygienic, healthy condition of room environment, while, in the contrary, it could throw questions of energy problem and public nuisance through its heat and gas dissipation to outside air. This paper, in the first place, declares how the setting of room enviroment conditions and the rationalization of sytem design affects the degree of energy consumption and cost, and then how the optimalization control of the system with the healthy condition as constraints and energy consumption as performance function is appropriate for optimization of air-conditioning itself. Computer control then becomes necessary as measures to accomplish optimization. The system and hierarchy of it are shown and overviewed. Prediction is necessary to practice optimal control, therefore severel practical and useful methods of estimation, which includes smoothing, filtering and predicting, are described with the stress upon those which are applied to Osaka Ohbayashi Building, the actual object of its application.

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The Air-conditioning system and computerized optimalizing system hardware of Osaka Ohbayashi Building are introduced, which are the motive force to drive this research and development. During the explanation, design technique of energy conservation and philosophy for environmental design and maintenance are stressed to be most important premises of optimization. The philosophy of air-conditioning system of the building are cooperative harmony between architecture and building services, minimum public nuisance, minimum energy consumption, effective use of public energy such as electricity and city gas, optimization and flexibility. Economy has the role as constraint. During the system design, muximum efforts were devoted to rationalization of design technique in detail in order to establish minimum energy with the environmental constraints such as temperature, humidity, air cleanliness from the viewpoint of concentration of dust and carbon-dioxides, which necessarily guided to apply optimalizing control to both air-conditoing and heat source system. Total figure of hardware and softwares of computer control is introduced.

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It was shown that the concentration of indoor air pollutants can be expressed by a single equation regardless of ventilation systems when new parameters B and R are used. B is the sum of the factors building up indoor air pollution, while R is the sum of the factors reducing pollution. Since the performance of ventilation systems can be evaluated simply by comparing B and R, simple rules are presented to determine B and R. A convenient way to calculate the change in the concentration of indoor air pollutants with time is also presented. Further, advantages and disadvantages of the pollutant reducing devices are discussed by examining their contribution to B and R.

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Investigated in the present study are the heat transfer characteristics of tubes in which the flow around tubes inclines against the direction of upstream uniform flow. A measured tube bank of in-line arrangement constitutes of five lines and seven rows having c_x/d=c_y/d=1.2 in the Reynolds number from 10^4 to 4×10^4, where c_x and c_y denote the streamwise and crosswise tube spacings respectively. Main results obtained are as follows. Severe asymmetry is produced in the local heat transfer and static pressure behaviors. It is found that the local heat transfer coefficient on the upper half of tubes differs at most 50% from that on the lower side.

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"Uniform Flow Ventilation" in this research means a ventilation used wide and unidirect air flow which has even velocity distribution, and therefore very effective to sweep out contaminated air in the room without diffusion. In this research, paying attention to the stream line of flowing air in the room, it is intended to study characteristics of uniform flow ventilation system, not only in the case that the room is generally ventilating (general ventilation), but also defined space of the room is ventilating (local ventilation). This is the first report of the research, and it is described at first how the stream lines change by simulation way of the air flow passing through the room, next that the equation to calculate diminishing concentration of toxic gas in the room introduced from above mentioned view, and furthermore, experimental result of gas concentration in the model room is compared with calculation value.

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