The reduction of intake of outdoor air volume in air conditioned buildings, adopted as the strategy for saving energy, has caused sick building syndrome abroad. Such symptoms of sick building as headache, stimuli of eye and nose and lethargy, appears to result from cigarette smoke, folmaldehyde and volatile organic carbons.
On the other hand, in airtight residences not only carbon monoxide and nitrogen oxides from domestic burning appliances but also allergens of mite, fungi, pollen and house dust, have become a subject of discussion.
Moreover, asbestos and radon of carcinogen now attract a great deal of attention.
Those indoor air pollutants are discussed.

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The following conclusions are obtained, studying properties of spray dried food and drying characteristics.
(a) Dried particles are similar to spray droplets in size distribution (y=2.5), and particle count distribution is arranged as (dn/dx = ae^-bx).
(b) The ratio of the particle diameters before and after drying is calculated with moisture before and after drying, and porosity is given as (ε_p = w_w⁴).
(c) The standard drying method is presented to evaluate accurately drying problems at a certain standard.
(d) Equilibrium moisture at 20 up to 100°C are summarized in terms of adsorption potential.
(e) It makes clear that calulation based on the theory of residence time and drying time represents well complex spray drying characteristics.

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Investigation of heat transfer characteristics in an ice making cold energy storage using a set of horizontal cooling pipes was carried out experimentally. Cooling pipe arrangement, number of pipes used and initial water temperature were varied, and temperature distribution in the tank and the volume of ice formed around the pipe were measured. Natural convection was also observed visually. During the experiment, two kinds of layers were observed. One is the layer where ice forming is interfered by natural convection and its temperature decreases rapidly with an almost uniform temperature distribution, and the other is the layer where ice forms steadily under a stagnant water condition. The former was called that the layer is under a cooling process and the latter that the layer is under an ice forming process. The effect of the experimental parameters, such as the arrangement of the cooling pipes, the number of pipes, the initial water temperature and the flow rate of the cooling medium, on the cooling process and the ice forming process were discussed. Approximate analysis was also carried out and compared with the experimental results. Finally, the relationship between the ice packing factor, which is significant in preventing the blockade, and experimental parameters was discussed.

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This paper deals with thermodynamic analysis of absorption refigerating cycle by T-s diagram. To design absorption refrigerators or heatpumps, Dühring chart and concentration-enthalpy chart are often used. However, for developing a new cycle or for comparing absorption cycle with other cycles, like compression cycle or Carnot cycle, it is necessary to analyse absorption cycle by means of T-s diagram. Moreover, with T-s diagram one may easilly find out how to improve the cycle, where the heat loss exist, or what the cycle looks like.
So, after analysing absorption cycle theoretically, we drew T-s diagrams of single effect and double effect cycle, with the result that absorption cycle is consist of heat engine and refrigerator whose areas in the T-s diagram are equal each other. Also we compared absorption cylce with other cycles and found out that absorption cycle can be "Carnot cycle" or "Lorentz cycle" by adding or improving heat exchangers.

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Gas viscosity of non-azeotropic mixtures of R12 and R22 was measured by an oscillating disk viscometer of the Maxwell type at 298.15~398.15K and pressures up to 6 MPa with an error of 0.2%. An empirical equation was obtained for the viscosity as a function of composition, temperature and density. This equation reproduced the observed viscosity with a maximum deviation of 2%. Normal pressure viscosity was found to be predicted with a maximum deviation of 2.5% by the Sutherland-Thiesen equation, the coefficients of which were approximated by Brokaw's method.

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Today it has become imperative to save energy by operating a refrigerator in a cold storage executed by external insulate reinforced concrete wall intermittently.
The theme of the paper is to get the evaluation method to be capable of calculating, numerically, interval time for stopping the refrigerator, in applying reinforced concrete wall as source of stored heat.
The experiments with the concrete models were performed in order to examine the time variation of internal temperature after refrigerator stopped.
In addition, the simulation method with three dimensional unsteady FEM for personal-computer type was introduced for easily analyzing the internal temperature variation.
Using this method, it is possible to obtain the time variation of internal temperature and to calculate the interval time for stopping the refrigerator.

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Thermal characteristics of heating towers for air-source heat pumps are studied in terms of the overall enthalpy-transfer coefficient. Ka. First. the method of counter-flow calculation is presented taking physical properties of ethylene glycol solutions into account. Next, both cooling-tower and heating-tower experiments are carried out in a small, induced-draft. counterflow tower packed with tubes of a staggerd arrangement. using water and commercial ethylene glycol solutions. The coefficient Ka measured in the heating-tower experiment shows a trend similar to that in the cooling-tower experiment. So. the data on cooling towers will be helpful to the thermal design of heating towers.

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Field tests and numerical calculations are described on the thermal characteristics of the cross flow heating towers using ethylene glycol solutions. continued from Part I for counterflow towers. First, a simple correlation factor method of crossflow calculation is proposed. Next, the data on the overall enthalpy-transfer coefficient. Ka. in a crossflow heating tower are presented and compared with those in a cooling tower of the same type. From the numerical calculations and discussions. diagrams and a simple relation are obtained useful for the design and performance tests of heating towers. The diagrams are expressed in terms of the number of transfer unit. flow ratio. A_L. And A_G as dimensionless parameters. The variation of thermal performace of heating towers may be expressed by the relation that A_L= const.

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The influence of variable viscosity on laminar flow heat transfer in duct with rectangular cross-section with small aspect ratio is investigated theoretically and experimentally to obtain fundamental information about plate heat exchanger for highly viscous liquids. The theoretical approach is a numerical solution of the momentum, continuity, and energy equations for two-dimensional duct flow. The variation of velocity and temperature distributions with flow direction are shown. The experimental approach presents the relation between average heat transfer coefficient and operating conditions. As a result, a correlation of Nusslt numbers is given. Experimental results are also presented for the heat transfer duct equipped with the inlet and outlet whose widths are smaller than that of the duct.

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Mean heat transfer coefficients are experimentally obtained for film condensation on a double swirl tube. Five different swirl tubes are used as a test tube that swirl pitch p is 28, 32, 40, 44 and 48mm respectively. From 113 is used as working fluid. The empirical correlations are proposed for predicting the mean condensation heat transfer coefficient.

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An experimental research has been made on performance of a shell and swirl tube type condenser. The double swirl tube has the following dimensions diameter of tube, 25.4mm; tube length of the heat transfer, 2952mm; swirl pitch, 36.0mm. The number of tubes used in the condenser is 30, and the actual total surface area is 7.42m². From 22 is used as working fluid. Empirical correlation are proposed in order to predicting the average condensation heat transfer coefficient and the water side heat transfer coefficient. The water side friction factor is about 0.09 at a Reynolds number of 3x10⁴.

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An experimental study has been made under the following conditions for convective heat transfer between the wall surface of a cavity of which both width and depth are 25 mm and the external main stream; the range of Reynolds numbers is from 10⁴ to 10⁵, and the ratio of tripping wire diameter to cavity width is 0.08. The oncoming boundary layer to a cavity is turbulent by the tripping wire with the existing study. Convective heat transfer between a cavity wall surface and the external main stream is treated by the following two phenomena; one is the heat transfer which is related to the temperature difference between the wall surface and the fluid in the cavity, and the other the heat transfer which is related to the temperature difference between the fluid in a cavity and the external mainstream. Experimental data obtained for the foregoing conditions is almost coincide with the existing dimensionless correlations of two of the authors.

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