• Journal of Energy Engineering
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• v.24 no.1
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• pp.132-136
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• 2015

The objective of this study is to investigate the effect of biodiesel blending on spray and combustion characteristics. In order to this, blended fuels containing 0, 5, 20, 50, 100% biodiesel in weight fraction was injected via common rail to constant volume combustion chamber. As a result, spray cone angle decreased and the Sauter mean diameter increased because of the higher dynamic viscosity and density of biodiesel, however, it does not seemed that spray penetration was affected by these factors considerably. In the combustion experiment, ignition delay of biodiesel was shorter than that of diesel due to higher cetane number. And the peak value of heat release rate increased and the end of combustion was advanced owing to higher combustion efficiency cause by the characteristic of oxygenated fuel.

• Journal of the Korean Chemical Society
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• v.39 no.7
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• pp.513-523
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• 1995

Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are the most concerned toxic organic pollutants to human. Because of their extremely high toxicity and uncertain genotoxic potential, their determination in environmental and biological samples is of great interest. Municipal solid waste incinerator facilities have been reported as the major contributors of dioxins and furans to the environment, and their formation from combustion is a universal phenomenon, everywhere. In this study dioxins and furans were analyzed from the bottom ash produced during combustion in an municipal waste incinerator located in Seoul. The EPA method was modified for sample pretreatment: the soxhlet method was used for extraction and clean-up procedures were performed by using silica and basic alumina, excluding active-carbon. The extract was then analyzed by HRGC/HRMS. A general trend of increase in the amounts of 6∼7 chlorine-substituted dioxins and furans was observed. Total dioxins, furans and 2,3,7,8-TCDD were determined as 8.05 ng/g, 4.75 ng/g, and 6.93 pg/g, respectively.

• Journal of the Korean Society of Propulsion Engineers
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• v.3 no.4
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• pp.44-50
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• 1999

For the prediction of combustion performance of the Unlike Impinging Quadlet Injector (OOOF type), mixing efficiency, mixing characteristic velocity, and efficiency of mixing characteristic velocity were obtained from the cold test. Water/kerosene were used for simulants, The momentum ratio of oxidizer and fuel were mixing correlating parameter. Orifice discharge coefficient, spray pattern and mass distribution were measured. As a result, invasion-depth had strong effect on mixing efficiency, mixing characteristic velocity, and efficiency of mixing characteristic velocity. Mixing efficiency and efficiency of mixing characteristic velocity showed maximum value for momentum ratio 1.67(TMR = 2.5), and fuel rich state showed larger decreasing ratio than oxidizer rich state.

• Fire Science and Engineering
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• v.25 no.3
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• pp.57-62
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• 2011

The combustion characteristic was evaluated for Pinus densiflora, used as a building material in Hanok, which were treated with two different flame retardant method. The specimen was brushed with flame retardant liquid two or three times and then let the specimen dehydrated during 24 h for spreaded treating. And the other specimen was soaked in the liquid for 72 h. The test methods were inflammability test using meker burner and heat release rate test using cone calorimeter. As a result for the tests, flame retardant treated specimens met the requirements of the inflammability and the spreaded treated method was more efficient than immersed method. The spreaded treated specimen had lower combustive properties than immersed specimen in TTI (time to ignition), PHRR (peak heat release rate), MLR (mass loss rate) and THR (total heat release).

• Applied Chemistry for Engineering
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• v.27 no.1
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• pp.39-44
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• 2016

This study was to investigate the characteristics of combustion toxic gases of pinus rigida specimens treated with chemical additives such as pyrophosphoric acid (PP)/ammonuium ion ($NH_4{^+}$), methylenepiperazinomethyl-bis-phosphonic acid (PIPEABP) and $PIPEABP/NH_4{^+}$. Each pinus rigida plates was painted in three times with 15 wt% of each chemical additives in the aqueous solution. After drying these specimens at room temperature, the production of combustion gases and smoke was examined by the cone calorimeter (ISO 5660-1). As a result, the peak mass loss rate time (PMLR time) treated with chemicals was delayed upto 10.5~47.4% compared to that of using untreated specimen. In addition, the peak production of carbon monoxide ($CO\;_{peak}$) of 32.1~71.4% and total smoke release rate (TSRR) of 15.6~43.6% for test pieces treated with the chemical additive were higher than that of using the virgin plate. In particular, for the specimens treated with the chemical additive, the rate of smoke release (RSR) 29.4~41.5% was obtained higher than that of untreated plate except the specimen treated with $PP/4NH_4{^+}$. It can thus be concluded that the treatment using the chemical additive could partially increase the combustion-retardation properties of the species when compared to those of the virgin plate.

• Fire Science and Engineering
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• v.27 no.6
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• pp.57-63
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• 2013

This study was performed to test the combustive properties of Pinus rigida specimens treated with piperazinomethyl-bis-phosphonic acid (PIPEABP), methylpiperazinomethyl-bis-phosphonic acid (MPIPEABP), and N,N-dimethylethylene-diaminomethyl-bis-phosphonic acid (MDEDAP). Pinus rigida Plates were painted in three times with 15 wt% alkylenedi-aminoalkyl-bis-phosphonic acid solutions at the room temperature. After drying specimen treated with chemicals, combustive properties were examined by the cone calorimeter (ISO 5660-1). It was indicated that the specimens treated with chemicals showed the later time to peak mass loss rate ($TMLR_{peak}$) = (315~420) s than that of virgin plate by reduc-ing the burning rate except for $TPMR_{peak}$ (280 s) treated with DMDAP. In adition, the specimens treated with chemicals showed both the higher total smoke release rate (TSRR) (407.3~902.0) $m^2/m^2$ and $CO_{mean}$ production (407.3~902.0) $m^2/m^2$ than those of virgin plate. Especially, for the specimens treated with PIPEABP, 1st-smoke production rate (1st-SPR) (0.1250~0.1297) g/s was lower than that of virgin plate, while the 2nd-SPR (0.183 g/s) was higher. Thus, It is supposed that the combustion-retardation properties were improved by the partial due to the treated alkylenediaminoalkyl-bis-phos-phonic acids in the virgin Pinus rigida.

• Fire Science and Engineering
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• v.27 no.4
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• pp.21-26
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• 2013

This study was performed to test the combustive properties of Pinus rigida plates treated with bis-(dimethylaminomethyl) phosphinic acid (DMDAP), bis-(diethylaminomethyl) phosphinic acid (DEDAP), and bis-(dibuthylaminomethyl) phosphinic acid (DBDAP). Pinus rigida specimens were painted in three times with 15 wt% bis-(dialkylaminoalkyl) phosphinic acid solutions at the room temperature. After drying specimen treated with chemicals, combustive properties were examined by the cone calorimeter (ISO 5660-1). It is supposed that the combustion-retardation properties were improved by the partial due to the treated bis-(dialkylaminoalkyl) phosphinic acids in the virgin Pinus rigida. Especially, the specimens treated with chemicals showed both the lower total smoke release rate (TSRR) ($16.94{\sim}18.92m^2/m^2$) and lower $CO_{2mean}$ production (1.98~2.09 kg/kg) than those of virgin plate. However the specimens treated with chemicals showed both the higher peak mass loss rate (PMLR) (0.1250~0.1297 g/s) and higher 1st-smoke production rate (SPR) (0.0153~0.0167 g/s) than those of virgin plate. Compared with virgin Pinus rigida plate, the specimens treated with the bis-dialkylamimoalkyl phosphinic acids showed partially low combustive properties.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.701-704
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• 2008

Actuality, amount of electric power is rising together with business expansion. But the most power plant is consisted a thermal power. People have been burning fuel like a coal, and it bring the cinder concrete. Fly-ash is use to the high-degree in construction material, but in case of bottom-ash had been disused the whole quantity. Intermittently, the academic world laid his studies for bottom-ash. Thus, this study contents are a characteristic of be not harden concrete incorporating fine aggregate, a strength of harden concrete, elastic modulus and a unit mass. And there do for the sake to examine utility value of bottom-ash and improve of light weight concrete.

• Journal of the Korean Society of Propulsion Engineers
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• v.6 no.2
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• pp.37-44
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• 2002

A theoretical study of spray and combustion characteristics due to coaxial twin-fluid injection is conducted to investigate the effects of liquid jet property, droplet size, contact length and liquid jet velocity. Model is properly validated with measurements and shows good agreement. Prediction of jet contact length, droplet size, liquid jet velocity reflects genuine features of coaxial injection in physical and practical aspects. Both the jet contact length and tile droplet size are reduced in a linear manner with an increase of injector diameter. Cross sectional area of liquid intact core is reduced with augmented jet splitting rate, thus the jet is accelerated to maintain the mass continuity and with an assistant of momentum diffusion by burnt gas.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2009.04a
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• pp.557-563
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• 2009

FMVSS 302 수평 연소 시험법을 통과한 자동차 내장재의 열적 특성을 평가하기 위해서 콘칼로미터를 이용하여 시험을 수행하였다. 화재 위험과 관련된 착화시간(time to ignition), 열방출률(heat release rate), 질량감소율(specific mass loss rate), 감쇠계수(extinction coefficient) 그리고 연기요소(smoke factor)와 같은 여러 가지 요소들을 분석하였다. 최대 열방출률값은 시험편에 따라 232${\sim}$635kW/$m^2$으로 큰 편차를 보였으며, 연기요소 또한 99${\sim}$551MW/$m^2$로 큰 편차를 보였다. 보조매트의 최대 열방출률은 다른 시험편에 비해서 상대적으로 낮은 값을 보였지만, 총연기 발생이 다른 시험편에 비해서 상당히 높았다. 따라서 최대 열방출률과 총 연기발생을 함께 고려한 연기요소값은 상대적으로 다른 시험편에 비해서 높게 나타났다.