The results of subjective experiments to evaluate the efficiency of portable air cleaners for perceived air pollutants generated from tobacco smoke are described. The efficiency of the five types of air cleaners to remove perceived air pollutants was evaluated by voting of the panel in decipol value, and the efficiency to remove particulate was evaluated from concentrations of particulate. When the air cleaner is used within a room, ventilation rate can be reduced considerably for acceptable air quality and the amount of reduction in ventilation rate can be estimated using the removal efficiency of air cleaners against perceived air pollutants.

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In the previous report, BMO and JMA, the computer files consisting of the monthly weather data at more than 3700 stations in the world, were compiled. In this report, hourly values of the meteorological parameters, such as dry-bulb temperature, solar radiation, humidity ratio, nocturnal radiation, wind speed and wind direction, are estimated based on the monthly data in the two files. Hourly temperatures for a typical day of each month through a year are generated from the following values and equations: 1) monthly mean values of daily maximum temperatures, and of daily minimum temperatures (these values are included in the files), 2) the possible times of the day when the maximum and minimum temperatures occur, 3) the equations representing the curves between the maximum and minimum temperatures. To generate hourly temperatures for an extreme day, daily maximum and daily minimum temperatures corresponding to a given frequency level such as 5%, 10% or 20% of a cooling or a heating month are estimated from the data in the files, then the same method as used for a typical day is applied. Monthly mean daily global solar radiations through a year are included in the files. However, daily global solar radiation for a clear day is necessary for design cooling load calculation. Therefore, the multiple regression equation predicting the transmittance of the atmosphere for a clear day is developed. Using the equation, global solar radiation at solar noon can be calculated at any location in the world. Global solar radiations at the other times during the day are calculated according to the relation between daily and hourly solar radiations developed by Collares, Pereira and Rabl. The values of cloud amount, wind speed and wind direction at 6, 12, 18 and 24 GMT (Greenwich Mean Time) are included in the files. Based on the proposed interpolation methods, the hourly values for each of these meteorological parameters for a typical day of each month are generated. Relative humidities coincident with the maximum and minimum temperatures are included in the files. Hourly relative humidities through a day are generated by the same method as used for dry-bulb temperature mentioned above. Then hourly humidity ratios are calculated using hourly temperatures and relative humidities. Hourly nocturnal radiations are computed from hourly temperatures, humidity ratios and cloud amounts.

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This study intends to find out the design requirements of the shower devices which can take a shower with comfortable conditions and energy conservation, and also to propose the test methods for performance of spray of shower heads according to the experiments on the hydraulics and sensuous evaluation of users. In this paper, we analyzed the results of the hydraulic experiment that was carried out on the shower heads on the market. As the experimental results, first we showed the characteristics of the volume of water discharge from the shower heads of each spray type and the coefficients of fluid resistance of the shower heads. Next, we clarified that the hydraulic characteristics of the shower heads for a performance evaluation can be explained from the distributions of spray water and the coefficients of hydraulic pressure on the received surface.

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An apparatus was made to measure the shading coefficient of blinds. Some experiments were carried out with this apparatus using samples of two kinds of exterior blinds and one kind of interior blind. The relations between shading coefficient and solar altitude, slat angles were made clear. Using the results from the experiments and the air-conditioning load computer program HASP/ACLD/8001, the heat extraction from an office building by air-conditioning equipment in summer was calculated and the energy savings of exterior blinds were analyzed quantitatively.

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In order to select an optimal system for a certain district heating and cooling plant among a lot of candidates at the planning stage, it is necessary to run the simulation program using as precise air conditioning load as possible. Simulation results are gravely influenced by the characteristics of the district, for example, the composition of building use, the geometrical shape and thermal characteristics of each building. Therefore, it is important to estimate the most reasonable district heating and cooling load. In this paper, using design of experiment, a table for estimating the PAL value, estimating tables of the peak load and monthly load with hourly variations were prepared.

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This study deals with an effective use of the ground coupled heat pump system. This paper is Part 1 in the series. Objectives are to develop a computer simulation model for predicting the amount of heat exchange and temperature distributions where freezing and melting take place in the soil during heat extraction and storage, and to make experiments on these behavior for verifying the computer model. An explicit finite difference scheme was used to solve a couple of nonlinear partially differential equations concerning heat and moisture movement during freezing and melting in soil. The values of the temperature and the water content were obtained by applying the correlation between temperature and unfrozen water content in frozen soil. The thermal conductivity of soil which was the most important thermal property in this calculation was calculated by serial-parallel model which was consisted of four kind elements; soil particle, water, air and ice. This numerical model was verified in comparing the experimental results. Experiments were made in a small column with one end cooled below 0℃ at the laboratory. The changes of temperature distributions were measured. At the end of the experiment, this column was cut into ten pieces of 2cm thick and moisture content of each piece was measured. Given the measured initial and boundary conditions, the results of calculation were in accordance with the experimental results. The conclusion is that it is effective to apply this model to predict the temperature and moisture distributions in the soil.

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In case of a fancoil unit which supplies conditioned air in parallel to the floor near the bottom of the fancoil unit, the occupied zone is apt to be influenced by the draft usually. When the supply air velocity is decreased in order to avoid this, in some cases, a short circuit phenomenon occurs where the warm supplied air returns to the air inlet directly not coming into to the occupied zone. Here, with the method of three-dimensional numerical calculation similar to that introduced in the previous report, the study of the fundamental characteristics for this phenomenon and the influence of relating factors was carried out. As a result, it was shown that the short circuit phenomenon occurred at some Archimedes number frequently, and factors such as the supply air temperature, the supply air velocity, the width of air outlet of fancoil unit and the thermal characteristics of wall were deeply concerned. When the distribution of air velocity and temperature is nearly two-dimensional, a sort of hysteresis phenomena were sometme found when the short circuit is generated or not in the occupied zone under the different initial values of calculation even with the same calculating conditions.

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Highly efficient cooling systems for telecommunication and information processing equipment are becoming increasingly necessary as the equipment may be packaged in high density. Following air flow distribution systems are compared by cooling efficiency in a high heat density room. (a) Underfloor air supply and overhead return (b) Underfloor air supply and horizontal return (c) Overhead air supply and underfloor return (d) Overhead air supply and horizontal return The air flow systems are constructed for a real scale experimental room, which is 19.2m in length, 7.4m in width and 2.4m in height. The room air temperature distributions are measured on the condition of the high heat density from 300W/m^2 to 1000W/m^2 and several supply air flow rates. The distribution of inlet air temperature to the equipment is measured through the experiments. The relation between the supply air flow conditions and the inlet air temperature distribution is investigated. Experimental results are follows; (1) Under the same heat density, the same supply air flow rate, and the same supply air temperature, the underfloor supply and overhead return system (a) caused the smallest temperature distribution (standard deviation) of inlet air and the lowest average temperature of all the systems. (2) The overhead supply and underfloor returen system (c) and the overhead supply and horizontal return system (d) shows small temperature distribution. But they require the lowest supply temperature of all. The system (c) and (d) are not economical, because the lowest supply temperature needs larger cooling units or low efficiency of them. (3) The underfloor supply and horizontal return system (b) causes the largest temperature distribution. The system (d) requires lower supply temperature than (b). As a result, the underfloor supply and overhead return system (a) is best, because under the same heat density and the same supply air temperature, it requires the lowest supply air flow rate to realize the same average temperature and temperature distribution conditions. A ventilation ratio model for the system is proposed to describe non-dimensional average inlet air temperature to the equipment, named average temperature difference ratio, and standard deviation of temperature difference ratio. Average temperature diference ratio and its standard deviation are described by the ratio of supply flow rate to equipment intake flow rate and the ratio of equipment returned flow rate to equipment exhaust flow rate. Experimental results are attached to this simple mathematical model.

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Operating conditions and static characteristics of heat storage and release processes were investigated theoretically and experimentally for a previously proposed heat storage system, in which the heat storage medium is concentrated by using the latent heat generated during both condensation and evaporation processes of the compression type heat pump. Good agreement was obtained between experiental data in the full scale apparatus (cooling capacity: 70kW) and theoretical values. These results suggest that designs with optimum heat storage capacity to decrease the energy consumption of compression type heat pumps are possible.

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Reduction of heat loss from hot water drain pipe is important to establish a heat recovery system using waste hot water in residential buildings. Experimental study on the heat loss from horizontal hot water drain pipe, through which some amount of hot water is drained, is conducted in a laboratory. Effects of the material and gradient of pipe-and total volume and flow rate of drained water on the heat loss are investigated. An analytical model, which can evaluate the effects of many factors and does not consume much calculation cost, are developed. A set of numerical experiments using the analytical model is conducted according to the design experiment. Some significant factors which influence the heat loss are clarified and quantitative effects of each factor are expressed in the form of simple regression equations. These equations are useful to evaluate the energy saving design of drain pipe systems.

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