촉매 연소기에서 희박 예혼합기의 연소특성

서용석,강성규,신현동,Seo, Yong Seog,Kang, Sung Kyu,Shin, Hyun Dong 대한기계학회 1998 大韓機械學會論文集B Vol.22 No.12

The aim of this paper is to investigate combustion characteristics of lean premixed mixture stabilized by catalytic surface reaction. The catalytic combustor consisted of a catalyst bed and a thermal combustor. The catalyst bed was made of two stage, Pd catalyst in the first stage and Pt catalyst in the second stage. Auto ignition of lean mixture took place in the thermal combustor. Ignition temperature was about $810{\sim}820^{\circ}C$ at the fuel-air ratio of 1.5~3.0 % and the mixture velocity of 11~18m/sec. The position of flame front in the thermal combustor moved toward back as preheat temperature increased and fuel-air ratio decreased. The f1ame supported by surface reaction was stabilized without any flame stabilizers. NOx emissions from the catalytic combustor were below 2.0 ppm ($O_2$ 15 %) when gas temperature was limited below $1350^{\circ}C$. This result demonstrates that NOx emission from the catalytic combustor is much low comparing with conventional combustors.

엔지니어링 플라스틱과 액정고분자 블렌드내에서 상용화제의 역할

서용석,홍순만,황승상,김광웅 ( Yong Sok Seo,Soon Man Hong,Seung Sang Hwang,Kwang Ung Kim ) 한국화학공학회 1995 화학공학의이론과응용 Vol.1 No.2

LPG-톨루엔 겸용 저온 촉매버너의 연소특성에 관한 실험적 연구

서용석,류인수,강성규,신현동,Seo, Yong Seog,Ryu, Ihn Soo,Kang, Sung Kyu,Shin, Hyun Dong 대한기계학회 1998 大韓機械學會論文集B Vol.22 No.11

The aim of this study is to investigate the characteristics of the catalytic burner to bum LPG and toluene alternately which can be applied to the dryer of an acryl coating process of textile. It was difficult to obtain complete conversion when the catalytic burner was installed to downward direction. The catalytic burner was improved by introducing the forced diffusion combustion air and the premixing air. The optimal operating conditions for the newly improved catalytic burner were obtained. The catalytic burner for toluene mixture was also investigated to incinerate toluene mixture exhausted from drying process. Results showed that the catalytic burner could oxidize toluene mixture completely at the proper operating conditions. Finally, the catalytic burner to bum LPG and toluene alternately was applied to the dryer of acryl coating. By using the catalytic burner, benefits of energy savings and environmental protection were obtained.

병렬순환시 2중효용 흡수식냉온수기의 특성

서용석,Seo, Yong-Seok 한국설비기술협회 1993 설비 : 공조ㆍ냉동ㆍ위생 Vol.10 No.11

비료값 전격 인상 등 농자재값 폭등 문제에 대한 대응 방안

서용석,Seo, Yong-Seok 한국농업경영인중앙연합회 2008 한농연 Vol.66 No.-

저NOx형 하니컴 촉매버너의 개발

서용석,박병식,강성규,Seo,Yong-Seok,Park, Byeong-Sik,Gang, Seong-Gyu 대한기계학회 1997 大韓機械學會論文集B Vol.21 No.6

A catalytic burner was studied which can be used as a heater operated in medium temperature. Noble metal catalysts (Pd/NiO) were used, which were supported on alumina wash coated honeycomb. The maximum heat-resisting temperature of the catalyst is about 900.deg. C. Combustion efficiency of the catalytic burner reached more than 99.5 % at the excess air ratio above 1.25.NOx emissions were lower than 1.0 ppm at all operation conditions. The operation condition for a stable catalytic combustion was obtained. It was dependent on the catalyst thickness. The 30 mm thick catalyst showed the widest stable catalytic combustion region. Stable catalytic combustion region of 30 mm thick catalyst was the operation condition of excess air ratio 1.25 - 1.75 and heat flux 7 - 14 kcal/h center dot cm$^{2}$.

복합지반물질의 탄성계수 산정을 위한 균질화 해석

서용석 ( Yong Seok Seo ),임성빈 ( Sung Bin Yim ),백용 ( Yong Baek ),김지수 ( Ji Soo Kim ) 대한지질공학회 2006 지질공학 Vol.16 No.3

암반은 일반적으로 생성환경 및 지질학적 조건에 따라 균질하지 못하며, 특히 기질과 역의 성분차이가 심한 역암 또는 각력암이나 핵석 등은 복합물질로 구성된 암반에 해당된다. 이들 복합 지반물질의 역학적 특성은 역과 기질의 역학특성과 분포특성 등에 따라 달라진다. 사면과 터널 및 지하구조물의 설계를 위한 이들의 역학성 평가는 매우 중요하지만 일반적으로 행해지는 암반분류법에 의한 이들의 평가는 부적절하다. 따라서 본 연구에서는 복합지반물질의 역학성 평가를 위해 균질화법을 적용하였다. 역의 함유량, 크기, 기질의 고결도, 분급, 경사 등의 인자를 고려한 조합에 의해 총49개의 해석모델을 작성하여 탄성해석을 실시하였다. 해석결과는 역암이나 핵석같은 복합지반물질의 역학성 계산에 적용될 수 있다. Bedrock is inhomogeneous for its genetically diverse origins and geological conditions when it forms, and especially, conglomerates and core-stones are one of these typical composite geo-materials composed of weak matrixes and strong pebbles. Mechanical properties of these composite bedrocks, like a conglomerate, generally vary depending on the mechanical properties and distributions of pebbles and the matrix. Therefore, regarding the consequence of understanding mechanical property of bedrocks in the designing slopes, tunnels, and other engineering facilities, empirical rock classification methods generally applied in the mechanical property modeling may not be suitable and rather, we may need some other classification methods, or tests more specific for these inhomogeneous composite bedrocks. This study includes a series of analyses to see elastic behaviors and modulus of composite geo-materials using homogenization theory. Forty nine case models were made for the elastic analysis with considering 5 factors such as gravel content, gravel size, strength of matrix, sorting and dip angle. The results analyzed are applicable to calculate elastic modulus of composite geo-materials as conglomerates and core-stones.

울릉도 북동부 지역의 낙석재해 위험도 평가

서용석 ( Yong Seok Seo ),장형수 ( Hung Su Jang ),김광염 ( Kwang Yeom Kim ) 대한지질공학회 2012 지질공학 Vol.22 No.3

이종지질 분포사면에서의 3차원 사면안정해석

서용석 ( Yong Seok Seo ),이경미 ( Kyoung Mi Lee ),김광염 ( Kwang Yeom Kim ) 대한지질공학회 2011 지질공학 Vol.21 No.1

화강암과 안산암질 암맥이 공존하고 있는 붕괴사면을 대상으로 지질에 의한 전단강도의 차이를 반영한 3차원 사면안정해석을 수행하였다. 지질이 서로 다른 두 종류의 파괴면에 대한 전단강도를 파악하기 위하여 흙-암 경계면 직접전단시험을 수행하였고, 또한 상부 풍화토층에 대한 실내토질시험을 실시하였다. 시험결과 풍화토층에 비하여 흙-암 경계면의 전단강도가 낮게 나타났다. 사면내 지질분포의 차이가 안정성해석 결과에 영향을 주는 것을 알아보기 위하여 한계평형법을 이용한 2차원사면안정성 해석을 대표단면에서 실시하였으며, 사면내 분포지질에 따라 입력치를 다르게 할 수 있는 3차원사면안정성해석을 실시하여 2차원안정성해석과 그 결과를 비교하였다. 해석결과에 의하면 안전율이 건기시 0.92와 포화시 0.32로 모두 불안정하게 나타난 2차원해석결과와는 달리 3차원해석결과에서는 건기시에 안전율이 1.26, 포화시에 0.55로 나타났다. 이러한 결과는 사면내 지질분포를 고려할 경우 안정성 해석의 결과가 달라질 수 있음을 보여주고 있으며, 우기 직후 붕괴가 일어났던 점을 고려하면 3차원해석결과가 보다 현실적인 것으로 판단된다. Three-dimensional slope stability analysis was applied to a failed dual-lithology slope containing both granite and an andesitic dyke, taking account of the differences in shear strength of the different lithologies. A direct shear test of the soil-rock boundary was performed to examine the shear strength of two different types of failure surfaces within different lithologies, and a laboratory test was performed on an upper, weathered soil layer. The test results indicate that shear strength was lower at the soil-rock boundary than within the weathered soil layer. A representative geological section was subjected to two-dimensional slope stability analysis using a limit equilibrium method to assess whether the distribution of lithologies upon the slope influences the results of stability analysis. The results were then compared with those of three-dimensional slope stability analysis, for which input parameters can be varied according to the distribution of lithologies upon the slope. The three-dimensional analysis yielded safety factors of 1.26 under dry conditions and 0.55 under wet conditions, whereas the two-dimensional analysis yielded unstable safety factors of 0.92 and 0.32, respectively. These findings show that the results of stability analysis are affected by the distribution of different lithologies upon the slope. Given that the studied slope collapsed immediately after rainfall, it is likely that the results of the three-dimensional analysis are more reliable.

중력상쇄 및 미세중력(Microgravity) 모델에서 인간의 생리적 반응

서용석(Yong-Seok Seo),이대택(Dae-Taek Lee),이승범(Seung-Bum Lee) 한국생활환경학회 2006 한국생활환경학회지 Vol.13 No.2

Since the gravitational force is eliminated in space, human is exposed to an unfamiliar environment, to which man has not been experienced at the surface of the earth, and encounter various physical phenomenons. And man can not perform usual physical activity as he has done on the earth. This study examined various physiological mechanisms observed in human body in microgravity and simulated environments and provided physical and physiological responses exposed those environments. In addition, whether exercise would delay or exaggerate various physiological stresses delivered by microgravity was discussed. It is assumed that these information will serve in understanding space physiology.