Studies on the freeze denaturation of fish muscle proteins were reviewed with emphasis given to changes in their physicochemical and biochemical properties during frozen storage. Denaturation of actomyosin commonly occurs during frozen storage and side-to-side aggregation of myosin molecules apppears to major role in this reaction. The author's group performed freezing studies with isolated preparations of proteins from carp muscle, namely actomyosin, myosin, H-meromyosin, L-meromyosin, and actin. Freeze denaturation occurred with indvidual proteins as well as with their subunits. Not only aggregation but also some conformational changes were observed. Denaturation was inhibited in the presence of added glutamate.

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Experiments were performed to investigate feasibility of using organic materials as a PCM for a latent heat storage unit of a natural circulation cooling/latent heat storage system. This system was designed to cool a shelter accommodating telecommunication equipment located in subtropical deserts or similar regions without using a power source. Taking into account practical considerations and the results of various experiments regarding the thermodynamic properties, thermal degradation, and corrosiveness to metals, lauric acid and iron was selected for the PCM and the latent heat storage unit material, respectively. Cyclic heating and cooling of the latent heat storage unit undergoing solid-liquid phase change was repeated for more than 430 days. The results showed that the heating-cooling curve was almost unchanged between the early stage and the 1,870th cycle. It was concluded that the latent heat storage unit could be used safely for more than ten years as a component of the cooling system.

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Experimental and theoretical studies were made of the heat transfer characteristics of a latent heat storage unit used for a natural circulation cooling /latent heat storage system. Heating and cooling curves of the latent heat storage unit undergoing solid-liquid phase change of a PCM (lauric acid) was obtained by using anatural circulation loop of R22 which consisted of an electrically heated evaporater, a water cooled condenser and the latent heat storage unit. The latent heat storage unit showed a heat transfer performance which was high enough for practical use. An approximate theoretical analysis was conducted to investigate transient behavior of the latent heat storage unit. Predictions of the refrigerant and outer surface temperatures during the melting process were in fair agreement with the experimental data, whereas that of the refrigerant temperature during the solidification process was considerably lower than the measurement.

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Experiments and statistical analysis were carried out to study the effect of cooling rate and surface area on freezing temperature of supercooled water attached to a heat transfer surface. Electrolytically polished copper disk was used and experiments were carried out under three kinds of fixed cooling rates (0.05K/s, 0.2K/s & 0.8K/s). In a case of experiments under high cooling rate, non-uniform temperature distribution existed on the surface, so the analytical method introduced in the former paper could not be applied. Hence another method was introduced here. The heat transfer surface was divided into a few parts so that in each part a temperature distribution on the surface kept uniform. The probability for the whole surface was taken as a combination of the probability for each part. By using this method, the probability of ice appearance within a unit surface area in unit time interval was calculated for each series of cooling rate. The results were compared and was observed that the probability of ice appearance was independent of the cooling rate and the area used for the experiment. Hence the reliability of using the method to predict the most probable freezing temperature of supercooled water introduced in this paper was clarified.

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The evaluation and the improvement on the contact thermal resistance between fin collar and pipe making by mechanical expanding were investigated numerically and experimentally.
The main results obtained in this paper are as follows :
(1) By obtaining the calibration curves of temperature differences vs. thermal resistance (thermal conductance) between fin collar arid pipe surface, it may be possible to evaluate thecontact resistance by the simple experiment.
(2) Futhermore, by measuring the contact length between fin collar and pipe, it is clear that the optimum expansion ratio of pipe exist on the fin type heat exchanger.
(3) It has been confirmed experimentally that the better contact state between fin collar and pipe than the case employing flared collar was obtained by using straight collar removed flare part.

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An experimental study has been performed to investigate characteristics of the freezing heat transfer of layered air-water flow in a circular tube, in which cooled air and water co-flow. The experiments were carried out under a variety of conditions of water discharge, water temperature, tube-wall temperature, air discharge, and water level. Particular attention was focused on photographic visual observations of the developing ice layer along the tube wall. It was in general observed that there were two different regions characterizing the ice formation, one of which was the freeze-off region, and the other was the steady-state region. The onset of freeze-off was found to be predicted by the equation Fo=1.85Re_w^0.142Re_a^-0.03θ_c^-1.01(H/D)^1.31. It was also found that the mean Nusselt number might be described as the following equation : Nu_m=2.26×10^-1Re_w^0.80Re_a^-0.03$theta;_c^-0.788(H/D)^0.331.

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Experiments were performed to study the flow characteristics and heat transfer during condensation of non-azeotropic refrigerant blends (NARBs) of R114 and R113 in the annulus of a horizontal double tube. The inner tube was a 19.1mm o.d. corrugated tube with soldered wire fins on the outer surface. The outer tube was a 29.9mm i.d. smooth tube. Experiments were performed at two vapor mass fractions of R114 at the test section inlet of 0.23 and 0.36. The mass velocity of the test fluids ranged from 50 to 200kg/m²·s. The frictional pressure gradient data were correlated fairly well by an empirical equation for condensation of pure R11 and R113 reported in a previous paper. The double tube showed a significant heat transfer enhancement over a smooth tube value. The heat transfer coefficient for NARBs was considerably smaller than that for pure R113. The decrease was more significant for a low mass velocity. A dimensionless correlation for the vapor phase mass transfer coefficient was derived, where the dimensionless parameters for forced convection condensation from a vapor-gas mixture flowing normal to a cylinder was extended to the case of NARBs.

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To explore the quantitative effect of the lubrication oil on the thermal and hydraulic evaporator performance, the detailed structure of two-phase refrigerant (R11) and lubrication oil (Suniso 5GS) flow has been investigated.
Experiment has been performed using a transparent tube 20mm in inner diameter and 2600mm in total length as main test section, which was heated by surrounding hot water bath. This water bath also functioned as the visual observation section of the transition of two-phase flow pattern. Oil mass concentration was controlled initially, and circulated into the system. The void fraction at the main test section was measured by direct volume measurement using so-called "Quick Closing Valve" method.
Since the effect of oil on the transition of two-phase flow pattern is emphasized at the low flow rate, operation was made at relatively low mass velocity, 50 and 100 kg/m²·s, five different oil concentrations were taken. Throughout the experiment, the evaporation pressure was kept at 105 kPa.
In general, when contamination of the lubrication oil happened, the void fraction was decreasing due to the change of viscosity and surface tension and the occurence of the foaming. To correlate the void fraction as function of quality, Zivi's expression was modified to include the effect of oil concentration. The agreement between the data and this proposed correlation was favorable.
Finally, to take into account the effect of lubrication oil, the new flow pattern diagram was proposed.

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Compact heat exchager of serpentine type is mainly made of many straight and curved pipe, namely180°U-bend. In spite of the fact that almost half of heat transfer area is occupied by the curved section, up to now thermal and hydraulic characteritics of this section have been predicted assuming a straight tube. The existance of violent secondary flow and vortex, the flow direction circulating downward or upward, might be an important factor to determine the evaporator performance.
In consideration to the above, in order to make clear the fundamental thermal and hydrauric characteristic, a study on two-phase refrigerant (R12) including lubrication oil (Suniso 5GS) effect on these in return bend (U-bend) have been made.
The experiment was performed using a copper U-bend tube having an inner diameter of 8.7mm, thickness of 2mm and radius of curveture of 35.0mm. The total length of test section was 1965mm consisting of 655mm in upstream and downstream straight sections and 655mm in curved section.
To confirm the uniform heat flux and uniform change of quality (0.1) at each heating section, seat-hed and flexible heater was wrapped around the outside of the test section. To observe the two phase flow regime, the transparent U-bend glass tube was used, instead of copper tube.
The experment comporised systematic variation of mass velocity (100-250 kg/m²·s), mass concentration of lubrication oil (0-9%) and thermal equilibrium vapor quality (0.1-1.2). During the experiment, temperature of outside wall and pressure drop were measured and flow pattern was observed. As the results, the flow disturbance at the downstream of U-bend was violent at the wavy and stratified flow regime and the strong effect of lubrication oil was observed. The local pressure drop at the bend was five times lager than at straight tube. This factor was increased with increasing oil concentration. Finally, the emprical correlation to predict the pressure drop was developed.

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The authors had already clarified that the heat transfer behaviors between internal and external insulated reinforced concrete wall of cold storage are different each others when inside and outside temperature of wall is flactuating. From that conclusion, we must consider the application method of wall insulation of cold storages in actual design.
The theme of the paper is to get the analyzing method and unsteady heat transfer characteristics of concrete walls of cold storage during daily variation of outside temperature of walls, and to give the basis for efficient design and cost optimization of insulate wall of cold storage.
The difference of unsteady heat transfer characteristics between internal and external insulate wall, when outside temperature of the wall follewed daily varation, was clarified in experiment and in situ measurement of practical cold storage. The analyzing method with two dimentional unsteady FEM was introduced. Using this method, it is possible to obtain the time variation of heat flux, which is important basic factor for practical design of cold storage, through the wall.

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