The purpose of the present study is to obtain convective and radiative heat transfer coefficients for a clothed man from an engineering angle based on the heat transfer theory. The diameter of an unclothed man-equivalent thermal cylinder model was previously set at 18cm and by applying the dimensionless equations on convective heat transfer to the cylinder, the formula of the convective heat transfer coefficient for an unclothed man was theoretically derived and the formula takes into considerations natural and forced convection at the same time. Clothed condition was stood for by putting clothes on the unclothed man-equivalent thermal cylinder and the diameter of a clothed cylinder was assumed to vary according to the garment thickness corresponding to clo value. Based on the standard temperatures concerned at 1 clo-comfort condition, the convective heat transfer coefficients to each clothing worn were calculated. As the results of calculations, we obtained the loci for a clothed man which have a strong resemblance to the convective heat transfer coefficient for an unclothed man. Convective heat transfer coefficient for an unclothed and a clothed man; h_c=√^3<270V^2+23>(0.1≦V≦3.0m/s)[kcal/m^2・h・℃] Man's linear radiation exchange coefficient derived by developing absorption factor method is expressed by the product of the emissivity of the human surface ε_g, the temperature factor k and Stefan-Boltzmann constant σ, and the expression includes no emissivity of surrounding wall surface. With reference to the temperature regions where the convection coefficients were fixed, the radiation coefficient to clo value was calculated. The radiation coefficient has resulted in the values of 4.8 to 5.0kcal/m^2・h・℃ corresponding to 1.0 to 0.5clo and it is justified to use practically the radiation coefficient h_r=5kcal/m^2・h・℃. Radiation heat transfer coefficient for a clothed man; h_r=ε_gσk=4.8〜5.0(1.0〜0.5clo)[kcal/m^2・h・℃]

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A simulation program was developed for the analysis of the dynamic behavior and the energy consumption of air-conditioning systems. Load models, zone models, plant models and controller models are used in this program to describe an air-conditioning system as a closed loop dynamical system made up of a building, heating and cooling installations and controllers. Formulating the dynamic balance of heat and mass in a living space in the load model, the time evolution of room temperature and humidity is simulated in the zone model. The plant model describes the energy consumption of heating and cooling installations as a function of load, outdoor temperature and humidity, etc. The control signal in air-conditioning systems is computed in the controller model based on the system state, e.g., room temperature, humidity, heat storage tank temperature, etc. The simulation results were compared with measured data to prove that the dynamic behavior and the energy consumption of air-conditioning systems could be calculated with sufficient accuracy. An illustrative example was also shown to demonstrate the application of the simulation program to the determination of installations capacity, the design of controllers and the estimation of energy consumption.

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This paper proposes a reasonable method of planning the adequate number of the sanitary fixtures in office buildings in consideration of the type of business work. This method is based on the two investigations. One investigation was performed to obtain the characteristics of the fixture usage and the time for using fixture. The other was performed to investigate the user's impression about the lavatory using questionnaires sheets. The principal contents are as follows: 1. User's reaction when the fixture is already occupied. 2. The permitable access time of users without displeasure in case that the fixture is occupied by others. The number of the fixtures is estimated as follows. First, the behavior of the users is analysed with GPSS (General Purpose Simulation System), and the number is decided according to the comparison of the calculated access time with the permitable access time obtained from the questionnaires sheets. And the comparison between the calculated numbers and the data of NPC (National Plumbing Code) etc. is discussed.

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The branch pipe is one of the most basic elements in water pipe line systems. Because of engineering importance in the planning or design of piping systems, many studies on the evaluations of energy losses occurred in this pipe have been made for many years. In this branch pipe, when the static pressure becomes lower or the vapor pressure is high, the cavitation occurs in the junction of main and lateral pipes. It causes the detrimental side effects such as noise, vibration, sometimes cavitation damage. Therefore, it is significant to predict the occurrence of cavitation. However, the reports on cavitation in the branch pipe are hardly any. As far as the authors know, all of them are the studies on cavitation only in the T-shaped branch pipe. This paper deals systematically with the cavitation problems on the various types of branch pipes with a single lateral pipe (usual branch pipe) and with two symmetrical lateral pipes (oppsing branch pipe). The main pipe has about 30×30mm cross section. First, for the usual branch pipe, the aspects of cavitation occurrence were observed in detail, and the effects of the location of roundness at the junction part, the branching angle, and the cross sectional area ratio of lateral to main pipe on the cavitation performance were experimentally investigated. Then, for the opposing branch, the effects of the branching angle and the area ratio were clarified and compared with the experimental results of the author's previous paper for the T-shaped opposing one. In conclusion, following matters became clear. 1) The location where cavitation occured was as follows: In opposing branch pipe, it appeared in separating stream from upstream side edge of junction (u-type cavi.), and in secondary vortexes at branch part (v-type cavi.). In usual branch pipe, in addition to above two types, it might occur in separating stream from downstream side edge of junction (d-type cavi.). 2) For usual and opposing branch pipe: Increasing the branching angle and/or decreasing the area ratio, the critical cavitation number became larger. 3) For usual branch pipe: The roundness at upstream side edge of junction was effective to suppress the u-type cavitation, but one at downstream side edge made the occurrence of v-type cavitation easier.

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In the 1st report, the authors proposed the mathematical model in order to analyse the oscillating movements of the seal water in the drain traps with the leaks caused by every oscillation. We also verified that the computed values from the model agreed with the measured values applying the impulsive and the arbitrary wave forms of the negative pressure to the water in the S-traps. In this report, in order to investigate qualitively the water behavior in the traps in detail, we performed flow visualizations by applying the impulsive and the step wave forms of the negative pressure to the water in the P- and S-traps. Then, we observed the swing flow which moved toward the right or left channel in the two dimensional U-channel which was set up horizontally. The following conclusions were made as a result of the above mentioned experiments combined with the results on the 1st report. 1) The seal water applied by the negative pressure on the drainage side of traps, leaks with the oscillation into the drainage pipe. 2) The larger the negative pressure is applied to the seal water in the traps, the more it leaks. All water over the weir of the trap does not leak, but a portion of it does (see 2.1 (1) i). However, the amount of the leakage depends not only on the magnitude of the negative pressure, but on the time width of its wave form. 3) After the removal of the negative pressure, the water still remaining in the trap performs a dumped free oscillation. The water surface does not remain smooth and flat, but it has a complicated surface shape that varies with time. 4) In comparison between the S-traps and P-traps, the P-traps display the phenomenon that a portion of the water outflowing along the horizontal pipe flows backward and returns to the trap. On the Other hand, the S-traps have no such phenomenon. Eliminating the above mentioned phenomenon, both types of traps exhibit the same manner when the water in the traps is applied by the negative pressure. But regarding the residual seal water depth, the P-traps are better than the S-traps (see 2.1 (2) i and ii). 5) When the water in the trap is subjected to the extreme magnitude of the negative pressure (e.g. over-20cmAq), a pocket of air passes through the water in the trap and a portion of the water flies about with a splash (see 2.1 (1) ii and (2) ii). Although such an extreme magnitude of the negative pressure applied to the water in the traps is abnormally high, we have performed the additional severe experiments for the sake of our interest in the phenomena. 6) When the single impulsive negative pressure (about -25cmAq) was applied to the water in the traps, the residual seal water depth was -0.1cm in the S-trap (dia. 4 in.) and was 1.0cm in the P-trap (dia. 3 in.). But as stated in chapter 4, 1st Report, it is possible to break the water seal by timming when the successive pulses of the negative pressure are applied to the water in the trap even though the magnitude is minus two or three centimeters of the water column. 7) From the experiment of two dimensional flow visualization, it was clarified that the movement of the seal water shows a very complicated manner with the production and disapearance of the separation, the secondary flow, etc. (see 2.2). Therefore it seems that it is difficult to analyse the movement of the seal water using fluid-dynamics when taking such a micro-structure of the oscillating flow into consideration. Accordingly we proposed the macroscopic mathematical model and clarified its usefulness (see 1st Report). 8) In Japan the following is legally defined the depth of the seal water in the drain traps must be between 5 and 10 centimeters. The construction of the vent pipes must be made such a way that the difference between the pressure in the drain pipes working against the seal water and the atmospheric pressure does not exceed 25mm of the water column. However, as mentioned above, it is

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In the preceding reports we studied the energy savings on coil load and fan energy consumption of VAV systems in perimeter and interior zones. In this report we calculated the energy consumption, and proposed the thermal efficiency and energy saving index of air conditioning systems. The hourly heating and cooling loads for 365 days of year were calculated with the aid of HASP/ACLD 7101 and the standard meteorological data in Tokyo by SHASE. As to VAV systems we studied: one system was that which handled transmission loads with CAV and solar and interior space loads with VAV, and the other was that which handled heating transmission loads with radiators under the windows and other loads with VAV. As the minimum flow of outlet air of VAV systems, two values were set and computed respectively, that is, 50% of the maximum flow rate, and the greater one of 25% of the maximum and the minimum outside ventilation air. The thermal efficiency (TE) and energy saving index (ESI) were defined as follows: TE=(energy consumption of net loads [kW・h/a])/(total energy consumption of air conditioning system [kW・h/a]) ESI=(total energy consumption of each air conditioning system [kW・h/a])/(total energy consumption of the basic air conditioning system [kW・h/a]) The net load is the sum of room sensible heat load, room latent heat load and the minimum outside ventilation air load. As the basic air conditioning energy consumption, we adopted the mean energy consumption of 4-pipe induction unit system which was constantly intaking the minimum outdoor air without air to air heat exchanger during a whole year. As a result, in case of using air to air heat exchanger and adopting free air cooling, VAV system with radiators obtained the most energy saving, when the system was controlled by speed fan control and set by the above-mentioned less value of the minimum flow of outlet air because of the minimum energy consumption through carrier powers.

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The correlations of monthly average values of various weather elements in Fukuoka have been examined in the previous paper. This paper presents a study of the relations between solar radiation, which has not been referred to in the previous paper, and other weather elements (i.e. duration of sunshine and the number of days with snow cover). In the former part of this paper, the approximations on sine of solar declination (sin δ), square of solar distance (r^2), and equation of time (E_t), of Japan (24〜46°N) from 1960 to 2000, are made up via harmonic analysis. The approximations on daily & monthly possible duration of sunshine and on daily or monthly solar radiation providing there is no atmosphere, are also made up. In the latter part, monthly solar radiation Q^^-' is approximated by the following formula. Q^^-'/Q^^-=k^^-(0.1929+0.5036S^^-'/S^^-)(1+0.1245G_<10>) where Q^^-': measured monthly solar radiation Q^^-: monthly solar radiation providing there is no atmosphere S^^-': measured monthly duration of sunshine S^^-: monthly possible duration of sunshine G_<10>: ratio of monthly appearance of days with over 10cm snow cover k^^-: coefficient which implies the locality of meteorological stations The term "1+0.1245G_<10>" shows that when ground surface is completely covered with snow for a month, multiple reflection of ray may increase between ground surface and sky, and solar radiation may increase by 12.45% in comparison with the condition without snow cover. When the same radiometer is used in measuring, k^^- is a coefficient which shows the conditions surrounding meteorological stations. However, k^^- actually shows a correcting factor for the sensitivity of radiometers, as the stations have a different radiometer respectively. According to this paper, monthly solar radiation at some meteorological stations can be approximated by the above formula where solar radiation is not measured.

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Iron and steel and ferroalloy industries emit large quantities of waste gas containing magnetic particles. Our theoretical analyses and laboratory-scale experimental results have shown that high gradient magnetic filter (HGMF) is an effective method of removing small magnetic particles from those sources. In the lab-scale experiments, air-borne magnetic particles are collected by HGMF at a room temperature, however, actual steel and ferroalloy furnaces exhaust waste gases at high temperatures. Collection efficiency changes of HGMF with operating temperatures should be investigated to verify the potential use of HGMF as a dry-type gas cleaning system for the purpose of waste heat recovery and of reduction of water treatment cost. The objective of this paper is to survey the effect of gas temperature on collection efficiency of HGMF both theoretically and experimentally. The results of this investigation indicate that increasing the operating temperature reduces the particle collection efficiency due to the increase of gas viscosity and due to the decrease of magnetization of particles and wire netting. Experimental values of the collection efficiency per unit thickness of parallel stream type of magnetic filter at various temperatures between 20℃ and 300℃ have shown good agreement with the equation semiexperimentally obtained at a room temperature.

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To estimate the concentration of cigarette smoke perticles in indoor spaces, it seems to be very important to know the weight of smoke particles generated from one cigarette. However, reported values scatter considerably, depending on methods of measurement. To clarify this point, weight of cigarette smoke particles from a cigarette was measured in two ways; before and after diffusion into a room. The former was about 2〜3 times higher than the latter. It was confirmed that the difference was due to the evaporation of volatile materials in smoke particles through an aeration of the trapped smoke particles with room air and the light scattering measurement. It was shown that the values measured after diffusion into a room should be used for the estimation of the concentration in indoor spaces.

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This paper dealed with an analysis and a prevention of water hammer in water supply piping system of building. In the part 1 of this paper the authors analysed the classify of water hammer and the characteristic of closed gate as boundary condition of water supply piping, and applied the basic equation to experimental values. In the part 2 of this paper studies were made about a practical supply piping with coupling or water hammer arrester and the maximum pressure rising rates were analysed. And then, it was found to substitute the experimental values into the calculated values. So the authors could be ready to calculate the basic equations of water hammer in water piping system in biulding. As a result of these, the authors could dealed with the prevention system of water hammer in water supply piping design of building.

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