This paper reports on the findings of studies on the factors which affect odor emission from offensive odor materials in water. The physical factors, such as suspended solids, viscosity and temperature of the solution, chemical factors, such as pH value, and external factors such as movement of the water are determined. The findings are as follows: 1) The offensive odor concentration versus time can be expressed by emission transfer coefficient. K_L・a'=2.3031/tlogC_<Lt_1>/C_<Lt_2>…(1) K_L・a': emission transfer coefficient [1/h] t: retention time [h] C_<Lt_1>: concentration at time t_1 [mg/l] C_<Lt_2>: concentration at time t_2 [mg/l] 2) The emission effect of suspended solids, viscosity and temperature can be expressed as equation (2). log_eK_L・a'=log_eB+A・X…(2) B: constant A: coefficient of various effecting factors X: effecting factors[suspend solids (SS), viscosity (V_<is>) and temp. (T)] 3) The forms of the emission effecting factors for ammonia, trimethylamine, hydrogen sulfide, methyl melcaptan and dimethyl sulfide are found. 4) The movement of the water can be expressed as the overall oxyged transfer coefficient, and since it is related to the emission effect of offensive odors, it can be further expressed as on emission transfer coefficient from which equation (3) can be derived. Based on this equation, the movement of water can be divided as follows: K_L・a'=L・K_L・a^n…(3) K_L・a': emission transfer coefficient [1/h] K_L・a: overall oxygen transfer coefficient [1/h] L: proportional coefficient of dissolved oxygen in water and generating offensive odor material from water n: constant 1) Free surface/In case of air current on the water surface/In case of loose flow stream/In case of water falling 2) Agitation due to air being blown into the water 3) Agitation with an impeller

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The seal water movements in a trap caused by the negative pressure in a drainage pipe have already been simulated by using the mathematical model proposed in the previous paper. Transparent traps with a square cross-section were used in the paper. This paper uses a circular cross-section trap to observe the seal water movements, and to perform simulations to investigate the difference of the phenomena between the circular and the square traps and to determine the applicability of the previous mathematical model. The effect of the input pressure of these two types of traps on the three parameters (C, R and D) is clarified. Moreover, negative pressures with triangular and square waveforms are applied to these traps, the final water levels are computed, and the results are compared with the experiments. Conclusions are as follows; 1) Observing the seal water movements of the circular cross-section trap (P-type 3 in.) in the impulse-response experiments clarified that the movement behavior is almost the same as that of the square cross-section trap (Chap. 3). 2) The mathematical model and simulation techmiques presented in the previous paper are also applicable to the circular cross-section traps (Chap. 4). 3) The values of the parameters for both types of P-traps are slightly different. But, when the I_p-value (time integral of the input waveform) is increased, the patterns in each parameter (Fig. 4) do not depend on the shape of the trap cross-section. The parameters are almost constant from 0 to -2cmAq・s of the I_p-value. 4) Grasping the above effects and applying triangular and squarewave negative pressures to both types of traps, the final water levels are computed, experiments under similar conditions are performed, and the following results are obtained; a) When the time-width of the triangular and square waveform negative pressures remains constant and the magnitude is changed, the computed and measured final water levels show good agreement, and the final water levels descend monotonously as the magnitude of the pressure increases. When a square waveform negative pressure is applied to the traps, the water in the traps leaks more than when a triangular waveform negative pressure is applied (Fig. 5 and 6). b) When the magnitude of the square waveform negative pressure is made constant and the time-width is varied, the computed and measured final water levels show good agreement. As the time-width of the pressure increases, the final water levels drop to a constant value acording to the magnitude of the pressure, i.e. the increase of the I_p-values in the pressure waveforms does not always break the trap seal (Fig. 7 and 8). The values of the parameters (C, R and D) adopted in these computations are the constant values mentioned above. Because of the good agreement between the computed and measured final water levels, it can be said that these parameter values are suitable for practical purposes and the utility of this simulation technique on seal water movement is confirmed.

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The miter bend is one of the most elemental pipeline components. The flow in a miter bend has an extremely complex flow pattern consisting of vortices in the outer and inner separation zones and secondary vortices downstream. The results of the other investigations on such flow problems are used extensively in pipeline design, but are restricted, for practical purposes, to energy loss measurements in miter bends having a circular or rectangular cross section. For example, when a miter bend is installed in a suction pipeline where the static pressure is insufficient, or in a hot water supply line where the vapour pressure is high, cavitation may occur, causing noise, vibration, and further damage. Therefore, in pipeline design, not only the energy losses, but also the cavitation performances should be considered. This paper, clarifies cavitation and its critical condition in the most simple miter bend, i.e., a right angle bend with a square cross section, experimentally, then compares the cavitation performances of miter bends of different shapes. The results of the cavitation performance experiments are divided into three parts: the effect on cavitation performance of the angle of a miter bend with a square or circular cross section, the effects of the roundness of the corner edges of a right angle miter bend with square cross section, and the effect of the aspect ratio of a right angle miter bend with rectangular cross section. The cavitation mechanism in miter bends is studied qualitatively from the results of observation of the flow pattern and pressure distribution along the inner and outer walls.

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In practical water or hot water supply pipelines, two or more miter bends are often used in series. The fluid flow at the bend is complex, and it appears that if cavitation shoud occur at these bends, its performance should differ from that of a single miter bend, because of the mutual interference of the flows. Although many studies have been made on the energy losses and flow patterns of these bends, none have been conducted on their cavitation performance. This paper describes the cavitation performance obtained experimentally on the most elemental two-fold miter bends, i.e. two right angle bends with a square cross section in series in the horizontal plane, and U-type and S-type bends. It clarifies how cavitation in the first and second bends of each two-fold miter bend depends on the distance between the two bends, as compared to the results for a single miter bend. Then the cavitation mechanism is discussed qualitatively with the pressure distribution along the inner and outer walls, and the flow pattern in the vicinity of the bends is observed.

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The concentration of cigarette smoke particles was measured at various ventilation and smoke generation rates in three rooms. When a suitable mixing factor is used, the results can be expressed satisfactorily by a mass balance equation. The mixing factor is determined experimentally in two ways, and its dependence upon the ventilation rate and location is examined. The mass balance equation is then applied to estimate the average smoke concentration in a room where occupants are smoking. A method based on this estimation is proposed to keep the ambient concentration of respirable dust below the allowable limit.

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Many Materials which consist of substances having different thermal conductivities have been used in various engineering fields. It is necessary to obtain the thermal property of these materials in order to study the heat transfer problems concerned with these materials. The effective thermal conductivity of dispersed materials such as suspensions and emulsions, which are considered as homogeneous and isotropic in macroscopic view have been investigated theoretically and experimentally by Maxwell, Fricke, Hamilton et al., and predicting formulae have been proposed. However, there are other materials containing armature (steel frame, etc.) in matrix (concrete, insulation materials, etc.), and they are used in many fields such as architecture. The composite materials described above which are heterogeneous in macroscopic view are also dipersed materials in wider difinition. But, on the thermal conductivity of the composite materials, a few examples are written as the values of over-all coefficient of heat transmission, and there are little investigations. From this standpoint, in this paper, the thermal conductivity of composite materials are studied by numerical method, and the factors which affect thermal conductivity are analyzed, and the predicting formula containing several factors is proposed. Main results obtained are as follows: 1) The effect of armature on the temperature field is not proportional to its width but is arithmetically. 2) The over-all coefficients of heat transmission increase with increasing Biot modulus, but increasing rate becomes gradually small and the coefficients reach each values asymptoticaly. 3) The predicting formula of composite materials proposed in the present paper is λ_e^*=(λ_d^*+K-Kφ(1-λ_d^*))/(λ_d^*+K+φ(1-λ_d^*)) where, K=2.0D_d^<*n_1>L_d^<*n_2> This equation is able to estimate the thermal conductivity of composite materials to within ±3% in the range of the thermal conductivity ratio λ_d^*≦10^3, of L_d^*≦0.2, of D_d^*≦1.0 and of L_o^*≦5.0, and has wider range applicability than previous equations.

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The purpose of this paper is to develop a method to measure quantitatively the rate of evaporative heat loss from the skin surface for the evaluation of thermal conditions in hyperbaric helium environment. The characteristics of a measuring device proposed, Vapor Flow Meter, are tested, and the rate of local skin evaporation of two sedentary subjects are measured by using the proposed device in 4 ATA environment. Based on observed data, the relationship between thermal sensation votes, skin wettedness and mean skin temperature is discussed.

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In order to systematically investigate the dividing flow mechanisms in pipe junctions, the dynamic characteristics of the flow were determined computationally for the two-dimensional laminar flow fields of pipe junctions with different branching angles and areal ratios. The flow mechanisms were considered on the basis of the computed results.

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In the preceding paper, we have examined the determination of cooling and heating period in Fukuoka through our investigation on actual operation of office buildings. In this paper, based on the investigation data, we make a statistic research on the duration of cooling and heating and the structure of a building. And the periods are classified through the standard weather data of Tokyo, Osaka and Sapporo. According to the Multiple Regression analysis, a large building with a large amount of interior generated heat is to have longer cooling period while, on the other hand, it is to have shoter heating period. Multiple correlation of regrression equation is 0.708 concerning cooling period, and 0.758 concerning heating period. In classifying the periods through the standard weather data of Tokyo and Osaka, we can appropriate, by using Discriminant Function, the population parameter of Fukuoka instead of that of Tokyo and Osaka, which have actual investigated operation data. As for Sapporo, we have come to the conclusion that we are incapable of classifying the season by using the Discriminant Function with day average temperature, day average humidity ratio and integrated day total solar radiation.

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So far, the water supply and drainage systems of building plumbing systems have been designed independently. However, the water flows consistently from water supply to drainage at the plumbing fixtures and equipments in the system while its quantity, quality and temperature change, therefore building plumbing systems must be handled systematically. The authors feel that it is necessary to clarify quantity, quality and temperature transformation mechanism at the plumbing fixtures and equipments, and to establish a system design method reflecting it. This report first describes the transform mechanism concept and approach. The authors then examined a building generally and the fixtures, equipments and pipings partially, and define the transform coefficient so the transform mechanism can be handled quantitatively. Basic transform quantity data on the discharge characteristics of individual sanitary appliances have been collected and analyzed. The result of this analysis indicated that more experiments on the collection of data are needed. Therefore, the authors performed experiments on the transform mechanism of the circumference of a wash basin as a typical sanitary fixture, and examined the influences of the discharge characteristics by changing the piping and simultanuous discharge from sanitary fixtures.

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