Various advanced absorption cycles are studied, developed and invented. In this paper, their cycles are classified and arranged using the three categories: effect, stage and loop, then an outline of the cycles are explained on the Duehring diagram. Their cycles include high COP cycles for refrigerations and heat pumps, high temperature lift cycles for heat transformer, absorption-compression hybrid cycles and heat pump transformer cycle. The highest COPi is attained by the seven effect cycle. In addition, the cycles for low temperature are invented and explained. Furthermore the power generation • refrigeration cycles are illustrated.

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In order to design a rectifier in NH₃-H₂O absorption heat pump, the heat and mass transfer model for packed tower-type rectifiers was presented in the previous paper and it was found that the model could predict over-all mass transfer coefficient within 30(%) difference to the experimental data. Though the approximate calculation to design rectifiers is increasing important, the method of this prediction need many reiteration along the vapor and solution flow, which might not be the simplified way to design packed tower-type rectifier
Thus the approximate pr . edicting method was presented in this paper. In this way, over-all mass transfer Coefficient was easily deriveded using the rectification characteristic that was determined by the dimension and geometry of rectification packing. The calculation results showed good agreement with the experimental data, regardless of kinds of rectification packing.

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The absorption heat pump using water-LiBr solution as working fluid has widely been used for air-conditioning system in Japan. However, it is difficult to apply the system for various uses, such as the utilization of low temperature heat sources, refrigeration and air-source type heat pumps because of the properties of the working fluid. 2,2,2- Trifluoroethanol (TFE) /n-Methyl-2- Pyrrolidone(NMP)is expected to be one of the most useful working fluids for the absorption heat pump of such use. While a number of investigations are available for the heat transfer performal1ce of LiBr solution, no work has been carried out to find out the heat transfer coefficient of TFE/NMP mixtures although it is important to know the heat transfer performance of TFE/NMP mixtures to design each element of the heat pump.In this study, nucleate pool boiling heat transfer cofficients are measured for TFE/NMP mixtures in order to evaluate the heat transfer perfonnance in the generator which is one of the element of the heat pump.

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With the view of utilizing a freshwater fish, carp, rainbow trout and silver crucian carp, especially, for fish-paste products, the changes of gel-forming ability of the surimi from these fishes during frozen storage were examined.
The gel-forming ability of the surimi with the general cryoprotective additives decreased gradually during frozen storage, but the gel-forming abiIity of surimi with additives in six months after frozen storage was higher than that of additives-free surimi. Each surimi from the three fish species showed resistance to freezing in the order of carp>rainbow trout>silver crucian carp. The gel-forming ability of the surimi from these fishes is low, but the present freshwater fish surimi have the permissible abiIity used for the practical kamaboko making like sardine surimi. On the other hand, a high correlation between gel-forming ability of surimi and total myofibrilIar Ca-ATPase activity, solubiIity and amount of unfrozen water was found.

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In a reciprocating compressor having close distance between a suction pipe and a suction muffler, great part of refrigerant flowing from the suction pipe is directly sucked into the suction muffler. But a part of refrigerant leaks into the void space in the hermetic shell and contacts with the cylinder, the motor or other high temperature parts. The temperature rise of refrigerant due to this leakage decreases the efficiency of a compressor. Therefore the efficiency of the compressor increases with decrease the amount of leakage.
In this paper, the direct suction ratio (DSR) is defined as the ratio of the flow rate of refrigerant directly sucked to the total flow rate from the suction pipe, and measured with a new technique using digital image processing. The technique developed measures the temporal decrease of visible tracer particles filled initially within the hermetic shell of a compressor visualization model, and calculates the DSR from the rate of concentration decrease. The technique is applied to improve the performance of reciprocating compressor by modifying the shape of the suction pipe which gives higher DSR.
Although refrigerant flow velocity around suction pipe and muffler is required as a fundamental data for further improvement of the performance, there has been no report or paper which measures these data due to the difficulty in insertion of velocity sensor into hermetic shell. In this paper, flow velocity data obtained with a PIV (Particle Imaging Velocimetry) technique applied to compressor visualization model is also presented.

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Experiments were conducted to obtain row-by-row heat transfer data during condensation of downward-flowing zeotropic refrigerant mixture HCFC-123/HFC-134a on a 3x15 (columns x rows) staggered bundle of horizontal low-finned tubes. The vapor temperature and the HFC-134a mass fraction at the tube bundle inlet were maintained at about 50°C and 9%, respectively. The refrigerant mass velocity ranged from 9 to 34kg/m²s, and the condensation temperature difference from 3 to 12 K. The vapor phase mass transfer coefficient was obtained from the heat transfer data by subtracting the thermal resistance of the condensate film. The heat transfer coefficient and the mass transfer coefficient decreased significantly with decreasing mass velocity. These values first increased with the row number up to the third (or second) row, then decreased monotonically with further increasing row number, and then increased again at the last row. The mass transfer coefficient increased with condensation temperature difference, which was due to the effect of suction associated with condensation. On the basis of the analogy between heat and mass transfer, a dimensionless correlation of the mass transfer coefficient for the 4th to 14th rows was developed.

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This report refers to the single/double-effect combination absorption refrigerator, which is driven by waste heat from phosphoric acid fuel cells, and investigates the influence of heat supply conditions, for the purpose of the effectual utilization of the low grade waste heat such as hot water (60~90([°C]). Since waste heat from fuel cells is recovered in two forms of steam and hot water, there is a characteristic of mutual intervention between steam and hot water in absorption refrigeration cycle. For effective use of waste heat, it becomes necessary to clarify this characteristic of mutual intervention.
Accordingly, we inquire the effect of heat supply conditions on above mentioned characteristic by simulation. In addition to this, the cooling performance of the absorption refrigerators with two different ways to use hot water (preheating of solution type and generating refrigerant vapor in the low temperature generator type) is investigated. Through out the research, some knowledges for effective use of low grade waste heat are obtained

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This report refers to the single/double effect combination absorption refrigerator (parallel flow type), which is driven by waste heat from fuel cells, and investigates its characteristics whenthe solution flow rate and the distribution ratio of solution are controlled. Since the waste heat of fuel cells can be recovered in the form of steam and warm water, this absorption refrigerator utilizes them both simultaneously, and can thereby be applied to year-round cooling.
In controlling the solution flow rate and distribution ratio of solution, it becomes necessary to clarify the conditions under which the above factors are controlled. The extent to which these conditions can be satisfied becomes the domain in which the operations can be undertaken. Therefore the domain is clarified, and it is shown that an operating point at which the cooling capacity is greatest does exist. In addition to this, it is stated that this operating point varies according to the operating conditions. As a result, an indicator of the high efficiency operation of the absorption refrigerator due to the control of the solution flow rate, and distribution ratio of solution is obtained.

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This report deals with chemical refrigerating apparatus using silica-gel / inorganic-salt-solution pair. Experiments are conducted by changing concentration of inorganic-salt solution and adsorbent / refrigerant pair. The following results are obtained.
(1) The temperature of refrigerant in evaporator is lowered as decrease of inorganic-salt-solution concentration. (2) The available salt-concentration range as refrigerant are gained by supercooling in restricted temperature range lower than solidification temperature of solution. (3)Difference of minimum temperature among cooled refrigerants are little in low concentration region. (4)In concentration lower than about10wt%, refrigerants supercool and solidify suddenly. Accordingly these salt-solutions are not available in these region as refrigerants.

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