Mechanical removing processes of a mushy structure in an aqueous solution are observed. A rotating cutter moves along a horizontal cold flat surface continuously to remove the mushy structure. The mushy structure stacks on the tip of a cutter and floats up periodically in every 2-4 minutes. The amount of energy to remove the mushy structure from the cold surface is measured experimentally. In a rotating cutter method, the amount of required energy per unit produced ice mass is large when the rotating speed is large. The experimental results are compared with those of a reciprocating cutter method. A rotating cutter method is superior to a reciprocating cutter method in terms of area of a cold surface per unit ice production rate. When the cold surface area is larger than 620cm², the rotating method is superior to reciprocating method in terms of energy required to remove the mushy structure from the cold surface. The final diagram shows the relations among ice production demands, designing conditions and operating conditions of an ice production unit, which leads to the optimal designing and operating conditions.

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A new rolling piston type rotary expander was developed. The performance of the rolling piston type rotary expander was investigated experimentally. The following results were obtained.
(1) A rolling piston type rotary mechanism was effective to the small capacity expander. (2) Indicated efficiencies over 0. 88 were obtained at the condition of the relatively low expander rotation. (3) Influence of an expander rotational speed on the rotary expander efficiency was small, and expander efficiencies about 0. 8 were obtained at the rotational speed conditions of 35Hz to 68Hz.

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In this article, a calculation model that enables to predict two-phaseflow distribution in a multipass evaporator is proposed. The model considers the multipass evaporator as the combination of simple elements, i. e. straight pipes and T-junctions, and utilizes the correlations to predict the pressure drop at the elements. For the T-junction, however, we have so little knowledge, especially for the small diameter T-junction, that we make some experiments to evaluate the existing correlations for the junction pressure drop. We also do not have reliable model for predicting the phase separation characteristics, so that we used the empirical equations for liquid division ratio derived in our previous papers. By this model, gas phase flow distribution to each pass is determined as it makes the pressure at the outlet of each pass equal. Calculation results well predict the previously presented experimental data that were obtained under the condition of larger quality at the header inlet. The suitableness of this model suggests that the complexity of the two-phase flow distribution in multipass tube attributes to the phase separation phenomena in dividing two-phase flow at a T-junction

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A system with a water-embedded-trpe ice storage vessel is widely used because of its simple structure and compactness. However, the water-embedded-type ice storage vessel has a disadvantage, that is, the solidification rate is very small. The use of falling water film seems to be one of promising ways for solving this disadvantage. We have found in a previous study that the use of the falling water film is very effective, especially for high initial water temperatures. In the present study, we eexamined the performance of a faling-water-film-type ice thermal energy storage vessel with pratical size, having vertical heat exchanger plates. The ice making performance coefficient, η, increases with time, and it becomes am aximum value of 2.5, after that, it decreases gradually. In order to make ice efficiently, it is necessary to set a flow rate of refrigerant properly and to adjust a difference between the evaporating temperature of refrigerant and the freezing point of water so that the refrigerant evaporates in the heat exchanger plates overall.

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Recently, the new heat transfer medium, which fulfills both functions of heat storage and heat transportation, has been developed in ah eat storage field. Solid-liquid latent heat microcapsule slurry would correspond to the topical medium, so-called functionally thermal fluid. The preset study has clarified the latent heat storage characteristics of microcapsule slurry by making heat transfer enlargement with the help of slurry water pool boiling phenomenon. The paraffin wax at a melting point of 62°C was used as a phase change material which was packed into the microcapsule. The heating surface temperature and concentration of paraffin in the microcapsule slurry was selected as experimental parameters. As a result, the non-dimensional correlation equations of heat storage completion time and heat transfer were derived in terms of non-dimensional parameters.

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In order to make clear the deterioration and its control for the gel-forming ability of lizardfish, formaldehyde (FA) and tyrosine (Tyr) accumulated in the fillets packaged with air, nitrogen (N₂) and oxygen (O₂) were determined during storage at 5°C. Amount of Tyr had no increase, however, th at of FA increased especially in the samples packed with N₂ on the earlier periods of storage.
It was presumed that an enzyme trimethylamine N-oxide demethylase (TMAOase) in the fillets acts sufficiently under oxygen-deficient storage, and the produced FA is rapidly combined with fish protein, causing the deterioration of the gel-forming ability, before protease of fillets act on the fish protein.
These findings suggested that avoidance of oxygen deficiency during storage is eftective to keep gelforming ability of lizardfish.

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HFC407C and HFC410A were introduced as the alternative refrigerants for HCFC22 in air conditioner to follow the Motreal protocol. But HFCs were also regulated by the Kyoto protocol and natural refrigerants like hydrocarbon (HC) and CO₂ are researched and introduced in the market. Under these circumstances the compatibility of motor insulation materials for hermetic motor under alternative refrigerants and lubricants become important. In this paper we discuss the compatibility of magnet wires and films of hermetic motor for air conditioner under atmosphere of HFC407C and HFC410A with POE and PVE lubricants and also discuss it under atmosphere of R600a with mineral oil and CO₂ with PAG lubricant in comparison of conventional atmosphere.

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The functional fluid, which consists of oil. water mixture with additive, is changed into an ice slurry by cooling with stirring. This paper describes a new continuous ice slurry formation system. Experiments were carried out under various conditions of the supply time of solution, the stirrer torque, brine temperature and supercooling degree. As a result, the characteristics of ice recovery and ice formation process were clarified. And it was found that the sizes of formed ice particles gradually became uniform and spherical with time, and then, they could grow up to 3.5mm for about 10 hours. Moreover, the factors influencing the sizes of formed ice particles were discussed because the larger ice particles were expected to increase their melting rate. It was found that the sizes of ice particles became larger with decreases of the supercooling degree and cooling rate, and with increase of the stirrer wing diameter.

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As regards the supercooling phenomenon, which is important factor in encapsulated ice system, we studied the supercooling release agent using the microorganism. Though the ice nucleation active bacteria had the high super cooling releasing ability, it was proved that the performance gradually lowered in long terms continuous use, when the live microorganisms were used. In order to improve the sustainability of the super-coolingreleasing ability through the control of the metabolism of the micro-organisms, the effects of typical sterilization methods were compared using live E. ananas of which the releasing ability is the highest of some ice nucleation active bacteria. It was found that ultraviolet and gamma-ray irradiations produced excellent results in the thousands repeated freezing-melting tests of water to which sterilized E. ananas were added.
In addition, some thousands of heat storage capsules with ultraviolet sterilized E. ananas were built a prototype. From the evaluation of the total heat exchange of encapsulated ice system, high supercooling releasing ability was indicated.

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Recently, air quality in the air-conditioned space is one of the most important concerns for end users Mist formation from the heat exchanger in air-conditioners is one of the major problems in this regard. This paper deals with experimental investigation of mist formation from moist air cooled in a rectangular channel. The influence of relative humidity, inlet air temperature, inlet air velocity and channel width on mist formation formed on two parallel copper plates without special treatment in the channel is investigated. Two kinds of copper plates with hydrophobic coating and contaminated with oil-smoke are also tested to clarify the influence of surface conditions in the channel. Experimental results show that the air velocity is the most influential parameter, which is followed by the inlet air temperature for copper plates without special treatment. It is also found that the ΔT (temperature difference between inlet air and copper plates in the channel) required for mist formation is the lowest for the copper plates contaminated with oil smoke and the highest with that of hydrophobic coating.

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Characteristics of the self-evaporation of hot water in a vertical vessel with internal baffles were investigated experimentally by using a visual hot model. The experiment apparatus was designed by modeling Ruths' varying pressure steam accumulator, and consisted of a vertical straight vessel (100mm in diameter and 1500mm in height) and internal baffles such as a straight pipe (60mm in diameter) and tapered tubes which were installed concentric to the vessel. Self-evaporation experiments were executed under vacuum pressure conditions. It was found that a permanent circulation of hot water was naturally induced in the vessel macroscopically, and nucleation took place within the upper part of the internal baffles near the water surface along this water circulation. Self-evaporation could go on steadily and the temperature uniformity in hot water layer could be improved remarkably in comparison with the case with no internal baffles. In this case, large portion of the self-evaporation of hot water resulted from the hydraulic pressure loss during the upward flow motion in the inner pipe.

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