• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.969-970
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• 2012

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.11.1-11.1
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• 2005

• Proceedings of the Korea Society of Design Studies Conference
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• 2005.10a
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• pp.258-259
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• 2005

• Journal of the Korean Home Economics Association
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• v.42 no.1
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• pp.167-180
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• 2004

This study was carried out to investigate quality characteristics of chopped garlic stored at various temperature. Chopped garlic was stored at room temp.($25^{\circ}C$), refrigerator temp.($5^{\circ}C$) and frozen temp. ($-18^{\circ}C$) for 1, 2, 4, 8, 24, 48, 72 hours(room temp.) and 1, 3, 5, 7, 10, 15, 20, 30 days(refrigerator temp. and frozen temp.), respectively. Brown color, Hunter color value, vitamine C contents and flavor patterns by electronic noes of chopped garlic were measured. Fresh chopped garlic was used as control and garlic powder by hot air drying was used for comparisons. Brown color of chopped garlic increased with increasing storage time, and the intensity of that was reduced as following order such as chopped garlic stored at room temp., refrigerator temp. and frozen temp. Brown color of garlic powder was most dark amomg all the samples. The results of Hunter color value was consistent with then of brown color in chopped garlic, whereas those of garlic powder showed relatively low browning. Above results might be caused by the difference of measurement as only surface color was measured in Hunter color value unlike brown color. Vitamine C contents of chopped garlic decreased with increasing storage time, and in particular those stored at room temp. decreased markedly as retention of those stored at room temp. was 60％ of control after 1 day storage. Vitamine C retention of chopped garlic stored at refrigerator temp. was 78％ of control after 10 day storage and that stored at frozen temp. was 86％ of control after 30 day storage. At room temp., flavor pattern by electronic nose showed a difference between chopped garlic stored for 1hour and control, and showed occurrence of off odor after 1 day storage. Flavor pattern of garlic powder by electronic nose showed a mild flavor. Flavor patterns of chopped garlic stored at refrigerator temp. were similiar until 10 day storage, whereas those showed occurrence of volitile components after 15 day storage. Flavor patterns of chopped garlic stored at frozen temp. were similiar after 30 day storage, and especially those after 3 day storage were almost the same as control. Therefore it is desirable to store chopped garlic within 1 day at room temp. and within 10 days at refrigerator temp. And it is most desirable to store chopped garlic at frozen temp. as retention of quality characteristics was superior than other storage temp.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.12
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• pp.1078-1087
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• 2003

Kimchi refrigerator is a household electric appliance developed with the wholly domestic technology for maturing and keeping kimchi. However, the principle of keeping is not yet revealed obviously. This numerical study has been conducted to investigate the flow and heat transfer characteristics in a kimchi refrigerator. The effects of arrangement variation of a evaporation tube are examined. Also, the heat transfer characteristics through the insulation material are discussed in detail. The flow and temperature field was simulated using the commercial code of CFX-5.3. A natural convection flow is formed through about 5/6 region from the bottom within the keeping space and accordingly, the 90% region of kimchi containers satisfies the temperature requirement with 0$\pm$0.5$^{\circ}C$. The stagnant flow exists in the upper 1/6 region of the keeping space and accordingly, the stratified high temperature distributions appear in the upper region of kimchi containers. The upward shift of the start location of a evaporation tube improves the temperature concentration toward $0^{\circ}C$ but the pitch variation is of no effect. The heat fluxes on the insulation surfaces show two-dimensional distributions with being higher toward the center. Through the variation of insulation thickness, 3.5% saving of insulation material is obtained under the same heat transfer rate.

• Journal of the Korean Society of Safety
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• v.30 no.3
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• pp.38-44
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• 2015

For this study, fire tests were performed targeting household items (Sofa, Drawer, Refrigerator, Washing machine) using a large cone calorimeter (Large Scale Cone Calorimeter, LSC). The data were obtained focusing on the fire characteristic of the data when the actual fire occurs. The study results showed the following mean HRR of the household items; drawer 2843 KW, sofa 2939 KW, washing machine 719 KW, refrigerator 2907 KW, and THR is found in sofa 2202 MJ, drawer 1559 MJ, refrigerator 1193 MJ, washing machine 627 MJ. From the result, it could be found that the sofa can cause significant heat generation when the fire occurs, and the flashover tendency was found relatively high in compartment fire. In addition, a weight of the four our household items was reduced sharply in a similar time (20min before and after) degree after ignition. The drawer and sofa which has a high heat release can be considered to speed up the fire spread as their weight decrease rapidly and showed relatively weak to the fire compared to the refrigerator and washing machine.

• Journal of the Korean Vacuum Society
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• v.20 no.4
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• pp.243-251
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• 2011

An apparatus for measuring the refrigeration capacity of cryopump refrigerators including the pulse tube type being developed domestically and the GM type has been designed, manufactured, and tested. The refrigeration capacity of a commercial refrigerator was evaluated for confirming the measurement procedure and the operation performance of the apparatus. The measured 2-D refrigeration capacity chart showed the intrinsic characteristics of the refrigerator model used in the experiment. In this paper, design specifications and test results of the refrigeration capacity measurement system is reported and discussed.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.6 s.237
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• pp.763-771
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• 2005

This paper is an experimental study on the performance according to a capillary tube diameter and length in a domestic small multi refrigerator[kimchi refrigerator]. Pressure drop in a capillary tube is predicted by theoretical analysis and experimental method as the reduction of capillary tube diameter from 0.74 to 0.6 mm. The differences between experimental results and analytical results are mainly caused by friction factor in a capillary tube. Because there are no adequate equations used to calculate pressure drop of capillary tube diameter under 1.0mm. The empirical equations necessary for interpretation of capillary tube were derived from capillary tube test results data using curve fitting method. This study shows that the optimized designs of system, which is capillary tube length and refrigerant charge amount, are 2000mm, 83g at the capillary tube diameter 0.6mm and 3000mm, 73g at the capillary tube diameter 0.74mm. And capillary design tools and system matching techniques necessary for development of the kimchi refrigerator were also developed through this study.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.450-455
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• 1997

Scallop, Patinopecten yessonensis(Jay), cultivated in the cold east coast of Kwangwon region, Korea, is expected to be producted to about 50,000 tones in 2000 year. Freezing is one of the most effective methods applied for soraging seafoods. But, the domestic refrigerator with an automatic defrost system shows the temperature fluctuation during defrosting, thus might result in the deterioration of the frozen foods. In this study, the domestic refrigerator with an automatic defrost system, temperature fluctuation from -18 to -5$\pm$1$^{\circ}C$ and fluctuation intervals from 16 to 20 hr, was used for storing scallop. pH was decreased rapidly after 3 month storage, while the content of amino nitrogen was increased continuously. The TMA content of open state was increased very rapidly on 3 month storage and then increased slowly, whereas that of vinyl package increased slowly. The VBN content was increased almost constantly with no significant differences between storage methods. The TBA content was increased up to 3 month storage with the higher value in open state than vinyl package in the beginning periods of storage, and then decreased very rapidly. The number of total viable cell was increased continuously during storage with higher number in open state than vinyl package. The estimated shelf-lives of frozen scallop with open state and vinyl package stored at -18$^{\circ}C$ in the domestic refrigerator with an automatic defrost system were 3.55 and 3.78 months, respectively.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.4
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• pp.377-385
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• 2005

An analytical model was developed using the lumped mass parameter method to estimate temperature distribution of metal parts and refrigerant of the hermetic reciprocating compressor, All of the lumped mass has been equated with the first law of thermodynamics. In the delivered equation, correlations of heat transfer coefficient in the heat transfer equation were taken from open literature. The equations are solved by Gauss-Jordan method simultaneously. To verify the developed numerical program, an experiment was conducted with a domestic refrigerator. The compressor which had been installed at the bottom of the experimental refrigerator was modified to measure internal temperature. Model verification test was conducted at $30^{\circ}C$ outdoor temperature with variation of compressor cooling conditions. As a result, there is a good consistency between calculated temperature and measured one.