• Proceedings of KHEA Conference
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• 2006.10a
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• pp.114-114
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• 2006

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.124-128
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• 2011

The heat transfer rate in an oven is very important for the quality of cooking food. For a robust performance design in an electric oven, forced convection has been used rather than natural convection, in bake and convection mode. Forced convection heat trans for in a vented electric oven has been numerically evaluated using the commercial software FLUENT. CFD modeling of the electric oven involves three-dimensional, steady state, MRF fan model and DO radiation model. In this study, the electric oven cavity and fan modules are not simplified. Other research shows that the boundary condition can often lead to non-physical solutions, such as reverse flaw at the top vent. To remove this non-physical solution, control volume has been expanded at the nearby vent. This numerical analysis has been performed with dedicated experimental support. The results show that there is less than a 2.2% difference between the simulation and experimental data for the temperature profile of food. From this research we can use this oven simulation technique to make a better convection system in an electric oven.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.8
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• pp.450-456
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• 2013

The composite electric oven is one of the fixing utensil, various functions are required. Steam generating function, which is one of its functions, and allows various food cooking. The location of the outlet of the steam generator is designed around ease of installation, consideration of internal fluid is not. Distribution of the steam can not be non-uniformly. Accordingly, cooking time becomes longer, the energy consumption increases. As a result of the analysis, it was confirmed stagnation phenomenon of the internal flow through the interpretation of the calculations for the position of the outlet of the steam generator existing. Further, by computing the analysis of various locations of the outlet of the steam generator, we investigated the distribution and characteristics of the internal flow.

• Journal of Hydrogen and New Energy
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• v.30 no.2
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• pp.111-118
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• 2019

Greenhouse gas emissions have a profound effect on global warming. Various environmental regulations have been introduced to reduce the emissions. The largest amount of greenhouse gases, including carbon dioxide, is produced in the steel industry. To decrease carbon dioxide emission, hydrogen-based iron oxide reduction, which can replace carbon-based reduction has received a great attention. Iron production generates various by-product gases, such as cokes oven gas (COG), blast furnace gas (BFG), and Linz-Donawitz gas (LDG). In particular, COG, due to its high concentrations of hydrogen and methane, can be reformed to become a major source of hydrogen for reducing iron oxide. Nevertheless, continuous COG cannot be supplied under actual operation condition of steel industry. To solve this problem, this study proposed to use two alternative COG-based fuel mixtures; one with natural gas and the other with biogas. Reforming study on two types of mixed gas were carried out to evaluate catalyst performance under a variety of operating conditions. In addition, methane conversion and product composition were investigated both theoretically and experimentally.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.681-686
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• 2012

This study conducted autoclave and microwave treatments on dough to determine if there were any changes in quality after the dough was cooked into bread. Wheat dough after secondary fermentation was treated with a microwave (1 min), an autoclave (30 min), and both an autoclave and microwave (30 min/1 min). We then measured the pH, moisture content, color, texture, and sensory evaluation. The results showed that pH was slightly decreased when it was treated in an autoclave (baking and no baking) and autoclave/microwave (baking and no baking). When microwaved and baked, the moisture content most decreased compared to the control. In crust color, there were no considerable differences in lightness, redness, or yellowness compared to the control, except when microwaved (no baking). The lightness of the crumb color decreased, while redness and yellowness increased, when dough was treated with an autoclave (baking and no baking) and autoclave/microwave (baking and no baking). Hardness, gumminess, chewiness and shear force were significantly increased when dough was treated with an autoclave (baking and no baking) and autoclave/microwave (baking and no baking) compared to the control. In the sensory evaluation, there were no considerable differences in color, aroma, taste, or overall preference when microwaved and baked. Color, aroma, shape, and overall preference were the worst when the dough was treated with autoclave/microwave (baking and no baking). These results suggest that autoclaving and microwaving may reduce the quality of bread, and countermeasures to this problem are necessary.

• Food Science of Animal Resources
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• v.29 no.1
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• pp.62-67
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• 2009

This study was undertaken to develope a semi-cooked pork using oven to provide a more convenient recipe for food service systems. Pork sliced 2 or 4 mm thick prepared with a Korean traditional kochujang sauce was broiled in an oven, steam oven or on a pan. 4 mm-thick meat that was broiled in oven for 4 min at $170^{\circ}C$, obtained higher scores in sensory and color evaluations. In labor-concentrated food service kitchens, the inner temperature of the pork at $85^{\circ}C$ provoked the highest satisfaction. The assessments of color L was ordered as steam oven, oven and pan broiling. And a- and b-values of oven broiling were higher than those of the steam oven or pan broiling. The color values of the steam oven-broiled pork sliced 4 mm-thick were significantly higher than those of the pan-broiled (p<0.05). In sensory evaluation, the taste score of steam oven was better than other broiling with significant differences. Furthermore pork broiling in oven was tender with low score in cohesiveness and chewiness. Overall acceptability was ordered as pan, steam oven, and oven broiling. Thus it was expectable that international Korean traditional food can be made using oven for food service system. For the diversity of the menu in food service, however it need to develope the more convenient and simpler recipes with semi-cooked Korean food.

• Journal of Bio-Environment Control
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• v.18 no.1
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• pp.60-66
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• 2009

This study was conducted to investigate into the effective drying method for three greens such as bang-a (Isodon japonicus), aster (Aster yomena) and lettuce greens (Ixeris dentata) Nakai. We have dried three greens using the different drying methods, have made methanol extracts and have also determined the physiological activities in $1,000mg{\cdot}L^{-1}$ extracts. Total phenolic compound contents were most increased by 65.1 and $60.2mg{\cdot}L^{-1}$ in the extracts of bang-a and aster which were frozen dried, however, that in lettuce greens were oven dried by $51.2mg{\cdot}L^{-1}$. Total flavonoid contents were extremely much more in bang-a extracts dried in the oven by $70.6mg{\cdot}L^{-1}$, however, aster and lettuce greens extracts frozen dried by 53.9 and $35.8mg{\cdot}L^{-1}$. DPPH radical scavenging activity in bang-a extracts were greatly increased by 78.8% when bang-a were frozen and dried, however, that in aster were not significant by $89.8{\sim}90.9%$. DPPH radical scavenging activities in lettuce greens extracts were became highest in the order f oven drying (91.9%), natural drying (91.0%) and freeze drying methods (90.9%). Nitrite radical scavenging activities in bang-a and aster extracts were most increased in the natural drying treatment by 73.3 and 78.2%, however, that in lettuce greens extracts were highest in freeze drying treatment by 75.1%.

• Journal of Mushroom
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• v.18 no.1
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• pp.63-71
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• 2020

The present study aimed to investigate the biological activities and nutritional contents of extracts from three types of edible mushrooms (Pleurotus ostreatus, P. eryngii, and Hericium erinaceus) following different roasting treatments. Roasting by a household multi-oven (HR60) decreased the total polyphenol contents, as well as DPPH radical scavenging and nitrite scavenging activities compared with the fresh samples, and no significant difference was observed between the different roasting times. As a result of rotary drum roasting (CR) treatment, we could observe a decrease in the DPPH radical scavenging activity in all roasted mushroom samples compared with the fresh samples, whereas nitrite scavenging activity increased in roasted P. eryngii and H. erinaceus. Additionally, total polyphenol contents increased significantly in roasted H. erinaceus. In each roasted sample dried by HR60 and CR, the amount of palatable-taste amino acids (e.g., glutamic acid) and sweet-taste amino acids, including glycine, serine, alanine, and threonine, increased in P. ostreatus, whereas the amount of bitter amino acids, including leucine, isoleucine, histidine, valine, and methionine, decreased compared with the fresh samples. In P. eryngii and H. erinaceus samples, we also observed an increase in the amount of palatable and sweet-taste amino acids upon the roasting treatments; however, the amount of bitter amino acids increased simultaneously following the roasting treatments. These results suggest that CR treatment is more effective in increasing the biological activities and nutritional contents, such as palatable and sweet-taste amino acids, compared with HR60 treatment.

• 한국연소학회:학술대회논문집
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• 2006.10a
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• pp.36-41
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• 2006

A simplified model of plastic layer and internal gas pressure In a coke oven is presented. We calculate internal gas pressure using presented model. And results are compared with calculated results using experimental data. Results show the difference of internal gas pressure by coal composition. The model is used to show that the permeability at the resolidification end of the plastic layer is a key determinant of the magnitude of the internal gas pressure.

• Proceedings of the KAIS Fall Conference
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• 2002.05a
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• pp.49-51
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• 2002

산업 현장에서 많이 사용되는 정밀주조법은 왁스형 제작 공정이 수작업으로 이루어지기 때문에 시간과 비용이 많이 소요된다. 이를 쾌속조형기를 이용하여 신속하고 정밀하게 왁스형을 제작하는 공정을 개발하였다. 먼저 3D CAD 데이터를 SLS형 쾌속조형기에서 캐스트폼 분말을 사용하여 캐스트폼형을 만든다. 오븐에서 왁스를 용융시키고 여기에 캐스트폼형을 넣어서 왁스가 캐스트폼형의 공극에 함침되도록 한다. 천천히 냉각시킨 후 꺼내면 왁스형이 완성되며 이를 일반적인 정밀주조공점을 거치면 최종 금속 주물이 완성된다. 이 신공정을 이용함으로서 제작시간과 비용이 크게 단축되었으며 제품의 정밀도가 향상되었다.