• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.9
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• pp.2249-2260
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• 1995

An experiment of close contact melting of phase-change medium partially filled in an isothermally heated horizontal cylinder is performed which involves the volume expansion of liquid induced by the solid-liquid density difference. The solid-liquid interface motion and the free surface behavior of liquid were reported photographically. The experimental results show that the curvature of upper solid-liquid interface varied to flat as melting progresses. In addition to the varying interface shape, the melting rate increases with the lower initial height of solid and the free surface height of liquid increases linearly. The experimental results of molten mass fraction were expressed in a function of dimensionless time Fo.Ste$^{3}$4/ and agreed well with the analytical solutions.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.6 no.1
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• pp.17-22
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• 2010

A sliding accident on the road have a high percentage by road freezing, especially, it is often appeared at bridges and tunnel of freezing areas. Thus, the stability of road operations is enhanced by preventing a partial freezing phenomenon. According to the geothermal snow melting system analysis, a pattern of thermal conductivity is found out about pavement materials of concrete and asphalt when it is buried. For the feasibility study on geothermal snow melting system, analysis of the ground melting point when operating system, life evaluation of pavements and safety evaluation of pipes are performed.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.15 no.2
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• pp.196-203
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• 1986

The melting phenomena of horizontal cylindrical ice-bar immersed in water and air concentrically in the cylinder are experimentally investigated for the temperature range from $3.5^{\circ}C\;to\;2.5^{\circ}C$. The shapes of the melting ice-bar are recorded photographically by the shadowgraph method. The shadowgraphs of the melting ice-bar show that water adjacent to the bar flows upward for the temperature range from $3.5^{\circ}C\;to\;5.8^{\circ}C$ while above $5.8^|\circ}C$ the flow is downward direction. The local and average Nusselt numbers are obtoined with the recorded shadowgraphs and comparator. Melting shapes of the ice-bar in the air show the vortex motion in the bottom portion of the bar, whereas no vortex motion appears in the bottom portion when the bar is melted in the water.

• Journal of the Korean Society of Safety
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• v.38 no.2
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• pp.15-22
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• 2023

In this study, the process and the environment of a melting furnace, located in Workplace A in Chungnam Province was inspected, and the insulation resistances of electrical circuits and motors were measured, and their changes over five years (2017-2021) were analyzed. It was found that the exhaust fan, oil pumps #A and #B, and heater were installed in 2010. Their insulation resistances decreased from 2017. Specifically, the insulation resistance of Oil Pump #A decreased from 100 (㏁) in 2018 to 20(㏁) in 2021, an 80% reduction. The fast decrease in insulation resistance was due to the high temperature of the melting furnace affecting surrounding the electrical facilities. A safety management scheme on the electrical facility of the melting furnace was proposed.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.246-251
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• 2001

Solid-liquid phase change (i.e. melting or solidification) occurs in a number of situations of practical interest. Some common examples include the melting of edible oil, metallurgical process such as casting and welding, and materials science applications such as crystal growth. Therefore, due to the practical importance of the subject, there have been a large number of experimental and numerical studies of problems involving phase change during the past few decades. Also, this study presented the effective way to enhance phase change heat transfer.

• Journal of Power System Engineering
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• v.15 no.4
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• pp.42-47
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• 2011

The purpose of this study is to investigate the best melting condition with various winding number of a heating pipe, supplying quantity of engine coolant and coolant temperature at the inlet of the heating pipe. Also, it is to suggest getting method of an appropriate quantity of the agent for the urea-SCR system within 10 minutes. For this matter, this study identifies the temperature distribution of inside of urea-tank while it is frozen at the low temperature condition, and suggests the best melting condition of the frozen urea within 10 minutes. From the results, it was found that 2L of melted urea was obtained by the coolant flow rate of 200L/hr at $70^{\circ}C$ for 10 minutes from the start of engine operating.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.159.2-159.2
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• 2010

Asbestos is the collective name for a group of naturally occurring minerals in their fibrous form and hydrous silicates of magnesium and a mineral fiber that has been used commonly in a variety of building construction materials for insulation and as a fire-retardant. Asbestos has been used for a wide range of manufactured goods, because of its fiber strength and heat resistant properties. Nevertheless harmful of asbestos is quite serious. Exposure to airborne friable asbestos may result in a potential health risk because persons breathing the air may breathe in asbestos fibers. Continued exposure can increase the amount of fibers that remain in the lung. Fibers embedded in lung tissue over time may cause serious lung diseases including asbestosis, lung cancer. In this paper, we carried out as fundamental study for dispose of asbestos cement slate safely and perfectly. Melting Temperature of asbestos need to more than $1,520^{\circ}C$ and specially asbestos cement slate need more energy than that of pure asbestos. We need to decrease melting temperature of asbestos cement slate for economical efficiency. To the purpose, glass and bottom ash were chosen as additives for basicity control. we analyzed about properties of asbestos cements slate, melting characteristics on the additives ratio and temperature. We confirmed about harmlessness of melting slag through analysis of scanning electron microscope(SEM) and x-ray diffractometer(XRD).

• Journal of the Microelectronics and Packaging Society
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• v.7 no.2
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• pp.63-68
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• 2000

This paper introduces the partial melting process for solder application and characterization of its possibility using off-eutectic Pb-Sn alloy. In order to show that the liquid phase in the semi-liquid state maintains the wettability as the single-phase liquid, the wetting balance test are conducted with varying temperatures and compositions. The results are then compared with the surface tension of liquid, both measured and calculated, to examine the correlation. The results from this investigation indicate that the partial melting can yield satisfactory solder joints as long as the liquid phase acquires sufficient chemical activity. At a condition where the partial melting is effective, a direct correlation between the wettability and the surface tension is found to exist. All alloys are found to show a reasonable wettability in semi-liquid state.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.4
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• pp.413-420
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• 2008

In order to utilize cinder melting slag as a filter media to control the quality of early rainwater, its environmental stability was verified by heavy metal elution experiment and improved by pre-treatment. Possibilities of improving its function as an absorbent was considered. Absorption characteristics of melting slag before and after the pre-treatment were analyzed by heavy metal equilibrium and stationary-phase column experiments, which in turn were analyzed by comparison experiment with activated carbon. As a result of heavy metal elution experiment, every metal item existed in a much lower amount than the criteria or was not detected, implying that there is no problem recycling it. Absorption equilibrium experiment showed that the time for pre-treatment melting slag to reach the equilibrium was reduced, while the absorbed amount was greatly increased. Stationary-phase column experiment assures us that the elimination rate was not changed much by influx rate, pH and the change in packing volume rate, indicating that this melting slag can be used not only as a filter media to control the quality of early rainwater but also in many areas of water-processing.

• Journal of the Korean Society of Safety
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• v.31 no.6
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• pp.12-18
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• 2016

This paper describes an optimal design of electric snow melting mat on vulnerable walk zone. In order to design an optimal electric power of snow melting mat and protect pedestrians with a nonslip mat, with considering protection of environmental pollution from abusing of the de-icing salts added calcium chloride. We analyzed nine snow melting mats through verification experiment in the condition of $-5^{\circ}C$, depending on three different kinds of heating material, electric heating cable, carbon heating film and carbon textile film. As a consequence, the $150W/m^2$ carbon textile film mat for snow melting was identified as an optimal power input and functional performance for pedestrians' safety on vulnerable walk zone. It is expected that the $150W/m^2$ carbon textile film mat would be useful to reduce slip down accidents by human error.