• 대한기계학회논문집B
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• 제27권6호
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• pp.685-692
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• 2003

A numerical simulation of flame propagation in a micro combustor was carried out. Combustor has a sub -millimeter depth cylindrical internal volume and axisymmetric one-dimensional was used to simplify the geometry. Semi-empirical heat transfer model was used to account for the heat loss to the walls during the flame propagation. A detailed chemical kinetics model of $H_2/Air$ with 10 species and 16 reaction steps was used to calculate the combustion. An operator-splitting PISO scheme that is non-iterative, time-dependent, and implicit was used to solve the system of transport equations. The computation was validated for adiabatic flame propagation and showed good agreement with existing results of adiabatic flame propagation. A full simulation including the heat loss model was carried out and results were compared with measurements made at corresponding test conditions. The heat loss that adds its significance at smaller value of combust or height obviously affected the flame propagation speed as final temperature of the burnt gas inside the combustor. Also, the distribution of gas properties such as temperature and species concentration showed wide variation inside the combustor, which affected the evaluation of total work available of the gases.

• 한국염색가공학회지
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• 제33권4호
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• pp.238-249
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• 2021

In this study, the effect on flame retardancy and various physical properties when TiO₂ was added with a citric acid/phosphate complex acid catalyst together with Pyrovatex CP new (N-methylol dimethylphosphonopropionamide), a phosphorus-based flame retardant, was studied on cotton fibers. SEM-EDS analysis was performed to confirm the surface characteristics and surface element analysis of the flame-retardant treated cotton fibers, and a vertical carbonization test was performed to confirm the char formation capability and flame retardancy according to the phosphoric acid ratio. By comparing the LOI index before and after washing 10 times, the washing durability of the flame retardant solution containing the phosphoric acid catalyst and TiO₂ was tested by LOI index after ten washing cycles. In addition, the influence of the flame-retardant processing on the physical properties were compared including thermogravimetric analysis (TGA), tear strength and whiteness.

• Journal of Advanced Marine Engineering and Technology
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• 제38권9호
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• pp.1150-1155
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• 2014

강화플라스틱(FRP) 선박은 화재 시 화염확산을 막기 위하여 관련 구조 기준에 따라 기관실 주위 벽 내부를 난연성 수지로 3회 이상 적층하거나, 이와 동등한 방열재로 둘러싸야한다. 관련 난연성 적층용 수지 및 일부 난연재료(연질폴리우레탄복합체)의 경우 선박용 물건의 형식승인 시험기준에 따라 그 성능을 평가할 수 있으나, 방열재로 빈번하게 사용되고 있는 '겔코트'에 대한 성능기준은 명확하지 않은 실정으로 난연성 수지와 화재안전성능이 비교 평가된 바 없다. 본 연구에서는 FRP 선박을 건조하는 조선소를 대상으로 설문조사를 실시하여 사용 중인 난연성 수지 3종, 겔코트 4종, 방염도료 1종 및 폴리우레탄 복합재 1종에 대해 화염전파시험과 방염성능시험을 적용하여 그 성능을 비교하였다. 화염전파시험 결과 임계열유속(CFE) 기준으로 각 종별 평균값을 비교하면 폴리우레탄 복합재, 난연성 수지, 방염도료, 겔코트 순으로 양호한 것으로 나왔고, 겔코트는 3회 도포한 것이 6회 도포한 것보다 양호한 결과를 보였다. 방염성능시험 결과 탄화면적 기준으로 각 종별 평균값을 비교하면 방염도료가 가장 좋게 나왔고 난연성 수지와 겔코트는 유사한 수준으로 나타났다.

• 한국응용과학기술학회지
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• 제15권3호
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• pp.77-84
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• 1998

Two-component polyurethane flame retardant coatings were prepared by blending phosphate-containing modified polyesters(PMPEs) and TDI-adduct. PMPEs were synthesized by polycondensation of dimethyl phenylphosphonate, a flame retardant component, with 1,4-butanediol, adipic acid, and trimethylolpropane. The content of dimethyl phenylphosphonate was varied 10, 15, and 20wt% for the reaction. Various physical properties of these new flame retardant coatings were comparable to non-flame retardant coatings. Coatings with 20wt% dimethyl phenylphosphonate did not burn during the vertical burning test.

• 대한기계학회논문집B
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• 제28권4호
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• pp.389-394
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• 2004

An experimental study on the NOx formation of LNG flame in fuel staged combustor has been studied. The design concept of multi fuel/air staged combustor is creation of two separate flame, a primary flame is a act as a pilot flame for the secondary combustion stage combustion zone, where most of fuel bums. Experiments were performed on a semi-industrial scale (thermal input 0.233 MW) in a laboratory furnace and Liquefied Natural Gas(LNG) was used as a primary and secondary fuels. This study included parametric study to identify the optimum operating conditions which are primary/secondary fuel ratio, and primary/secondary air ratio for reducing NOx emission with two types of nozzle. The test demonstrated that NOx emission can be reduced by >70% in accordance with operating conditions.

• 한국정밀공학회지
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• 제23권12호
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• pp.56-63
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• 2006

This paper describes the development of automatic making system of a frame element for flame prevention. The frame element is made by turning a thin plate and a formed plate on the small pipe. The couple plate(two plates) should be pulled with constant farce to manufacture a good frame element. This is because if the gap between one couple plate and other couple plate is different, it will not prevent flame. In this paper, the automatic making system of a frame element for flame prevention was made, and which could automatically manufacture a frame element. The characteristic test of the made frame element by that system was performed, and its result was very good.

• 에너지공학
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• 제2권3호
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• pp.285-292
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• 1993

A cylindrical-shape, horizontal furnace was used to investigate the effect of particle size on the pulverized coal combustion behavior. Three differently-sized fractions (5, 30, and 44 microns in average diameter) of high-volatile bituminous coal, were burned in the test furnace. Ignition characteristics of pulverized coal flame were determined through the amount of methane in the carrier gas for the self-sustaining flame. Easiest ignition occurred with the immediately-sized coal particles. Ignition of coal jet flame appeared to occur through a gas-phase homogeneous process for particles larger than 30 microns. Below this limiting size, heterogeneous process probably dominated ignition of coal flame. Oxygen concentration of combustion air was varied up to 50%, to determine the oxygen-enrichment effect on the coal ignition behavior. Oxygen enrichment of primary air assisted ignition behavior of pulverized coal flame. However, enrichment of secondary air didn't produce any effect on the ignition behavior.

• 한국응용과학기술학회지
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• 제22권1호
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• pp.1-8
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• 2005

Chlorine-containing modified polyester polyols were synthesized by two-step condensation reactions. Intermediate was synthesized by the esterification of monochloroacetic acid with trimethylolpropane in the first step. Polycondensation of the intermediate (MCAOs), 1,4-butanediol, and trimethylolpropane with adipic acid was carried out. Two-component polyurethane (PU) coatings were prepared by blending MCAOs and IPDI-isocyanurate. There new flame-retardant coatings showed various properties comparable to other non-flame-retardant coatings. They were superior to flammable coatings from the experimental results showing rapid and 10 to 13 hours of pot-life. Coatings with 30wt% monochloroacetic acid was not flammable by the vertical flame retardancy test.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.161-166
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• 2001

An Experimental study on the NOx formation of LNG flame in fuel staged combustor has been studied. The design concept of multi fuel/air staged combustor is creation of two separate flame, a primary flame is act as a pilot flame for the secondary combustion stage combustion zone, where most of fuel burns. Experiments were performed on a semi-industrial scale (thermal input 0.233 MW) in a laboratory furnace and Liquefied Natural Gas(LNG) was used as primary and secondary fuels. The study included parametric study to identify the optimum operating conditions which are primary/secondary fuel ratio, and primary/secondary air ratio for reducing NOx emission with two types of nozzle. The test demonstrated that NOx emission can be reduced by >70% in accordance with operating conditions.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2004년도 추계학술대회
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• pp.189-195
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• 2004

It compared quality characteristics for the stone surface treatment system and its products. With the result, the flame burner equipment was mainly used to the surface treatment of granite, but it occurred greatly the high temperature, the rock fragment, the noise and dust. For the other side, the whetstone polishing machine for the polishing was a maintenance for the specific physical properties of stone, and it did not occur the stone fragment and the dust. The durability of the stone products due to the flame burner was investigated with that it falls to $20\sim25\%$ more than the surface treatment by the whetstone polishing. Share's hardness of the polishing products in the durability test showed more greatly index than the flame burner and conventional product. The polishing products of Pochon stone in the case of the abrasion resistance showed great more $15\%$ than the general products, more $9\%$ than the products by the flame burner.