• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.60-65
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• 2001

Bomb calorimeter was developed for measuring the calorific value of combustible matter such as wastes. The calorimeter consist of bomb, stirred-water type bucket, thermometer and ignition circuit. Operation and performance of the calorimeter have been tested experimentally. In the present study, calorific values of light oil, lamp oil and bunker C oil is measured using the bomb calorimeter. Mass of the sample is fixed at lg, and oxygen pressure in the bomb is used as an experimental parameter. Sample in the oxygen bomb is burned with electrically heated Ni-Cr wire of 100mm in length, and temperature of water in the bucket become increased by $5^{\circ}C$ during about 30min. Calorific value of the sample is calculated with the temperature difference of water. Combustion tests, such as the record of temperature history and the inspection of remnants, are performed at 4, 6, 8 and 10 atm of the oxygen pressure. From the test results, oxygen pressure in the bomb must be over 10atm for complete combustion.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2001년도 제22회 KOSCI SYMPOSIUM 논문집
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• pp.23-30
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• 2001

Bomb calorimeter was developed for measuring the calorific value of combustible matter such as wastes. The calorimeter consist of bomb, stirred-water type bucket, thermometer and ignition circuit. Operation and performance of the calorimeter have been tested experimentally. In the present study, calorific values of light oil, lamp oil, benzoic acid, ethyl alcohol and methyl alcohol is measured using the bomb calorimeter. Mass of the sample is fixed at 19, and oxygen pressure in the bomb is used as an experimental parameter. Sample in the oxygen bomb is burned with electrically heated Ni-Cr wire of 100mm in length, and temperature of water in the bucket become increased by $2{\sim}5^{\circ}C$ during about 30min. Calorific value of the sample is calculated with the temperature difference of water. Combustion tests, such as the record of temperature history and the inspection of remnants, are performed at 6, 8 and 10 atm of the oxygen pressure. From the test results, oxygen pressure in the bomb must be over 10atm for complete combustion.

• Journal of the Korean Wood Science and Technology
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• 제25권3호
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• pp.66-74
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• 1997

Liquid permeabilities of red oak and several softwoods were measured by the pressure bomb method and a modified liquid permeability method in order to investigate their efficacy. The effect of preboiling and prefreezing on wood permeability were also examined for both green and resaturated specimens. Regardless of some disadvantages these two methods were revealed as a handy tool for quick evaluation of the permeability of an unknown species. The permeabilities of the resaturated specimens increased when preboiled. but decreased when prefrozen. For green specimens, however, pre freezing increased permeability. The discrepancy of the pre freezing effect on two specimens partially attributes to their difference of initial permeabilities. For all species except radiata pine heartwood, the radii of the effective capillary pores, derived from the water potential equation, distribute from $0.42{\mu}m$ to $7.2{\mu}m$. Those of radiata pine heartwood are below $0.46{\mu}m$.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제24회 춘계학술대회논문집
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• pp.88-91
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• 2005

본 연구에서는 내부용적이 200cc와 700cc인 closed bomb법 이용하여 $1,000\sim30,000$ psi범위에서 고체 추진제의 연소속도를 측정하여 고체 추진제의 연소 특성을 고찰하였다. $5,000\sim15,000$ psi범위에서 두께 1mm의 디스크 형 시편으로 closed bomb법에 의해 측정한 연소속도가 $1,000\sim5,000psi$ 범위에서 strand burner법에 의해 측정한 연소속도와 잘 일치하였다. 200 cc와 700 co에서 측정된 연소속도는 bomb 부피에 상관없이 잘 일치하였다. HTPB/AP 추진제의 경우는 $5,000\sim7,000$ psi 범위에서 압력 지수가 급격히 증가하였다.

• 한국추진공학회지
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• 제12권4호
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• pp.1-6
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• 2008

본 연구에서는 내부용적이 200 cc와 700 cc인 closed bomb을 이용하여 30,000 psi까지 HTPB/AP 추진제의 연소 특성을 고찰하였다. 장전 밀도에 따라 closed bomb법에 의해 측정한 결과 연소속도는 $1,000{\sim}5,000$ psi 범위에서 strand burner법에 의해 측정한 추진제의 연소속도와 잘 일치하였으며, 측정 압력이 6,000 psi 부근에서 압력 지수가 급격히 증가하는 현상을 보였다. Closed bomb의 내부용적이 각각 200 cc와 700 cc일 때 측정된 연소속도는 내부용적의 크기에 상관없이 잘 일치하였다.

• 한국자동차공학회논문집
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• 제2권4호
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• pp.91-99
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• 1994

Tunable KrF Excimer Laser is used here for measuring OH and $O_2$ density distribustion in an open $H_2$/air premixed flame and in a combustion bomb. Laser Rayleigh Scattering(LRS) and Planar Laser Induced Predissociative Fluorescence(PLIPF) methods are used to obtain two-dimensional images of total and specific densities. Laser Excitation wavelengths are calibrated via flame images and combustion bomb images show good qualitative a greement with theoretical calculation. Furthermore images in a combustion bomb can be developed to study real Spark-Ignition engine combustions. Our experimental images show that there are no more collisional quenching problem at high pressure environment(including atmospheric pressure) using predissociative fluorescence technique. Further development to obtain two-dimensional temperature dustribution is ready to use eventhough it is not reported in this paper.

• 한국자동차공학회논문집
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• 제1권1호
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• pp.50-58
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• 1993

The ignition delay of diesel oil and fish oil blended with diesel oils was investigated at various pressure and temperature conditions in a constant volume combustion bomb. The evaporation and combustion duration of diesel oil and fish oil blended with diesel oils were respectively different in high and low temperature. The dependence of ignition delay on the temperature was different in high and low temperature ranges which were divided at the 773K. The dependence of ignition delay on the pressure was almost linear, regardless of the test fuels at the constant temperature(863K). The ignition delay became longer as the blending rate of fish oil increased at the constant temperature and pressure, but it was especially short with 20% fish oil blended with diesel oils.

• 한국항공우주학회지
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• 제39권12호
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• pp.1166-1173
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• 2011

고체 로켓 추진기관에 적용 가능한 전기-기계식 점화안전장치를 설계하고 제작하였다. 본 전기-기계식 점화안전장치는 로터리 솔레노이드를 이용하여 장전되고 내장된 전기식 착화기를 발화하여 점화 에너지를 발생시킨다. 점화안전장치의 점화 성능을 검증하기 위한 방법으로 10-cc 밀폐용기 시험(Closed Bomb Test)을 실시하였고 점화안전장치 작동시 발생되는 고온, 고압의 가스로 인하여 밀폐용기 내부에 형성되는 압력을 계측하였다. 10-cc 밀폐용기 내부에 형성되는 압력과 점화가스 유로가 열리는 시간 등을 이상기체 방정식과 질량 및 에너지 보존 법칙을 적용한 1차원 가스 동력학 모델을 통하여 계산하였다. 모델링 예측과 CBT 시험 데이터를 비교한 결과 점화안전장치에서 발생되는 가스에 의해 밀폐용기에 형성되는 압력은 약 34%의 효율을 갖는 것으로 나타났다.

• 한국추진공학회지
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• 제10권3호
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• pp.60-66
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• 2006

초고압(10000-20000 psia)에서 연소하는 추진제의 연소속도 특성을 연구하였다. closed bomb의 시편 시험을 통하여 약 4000 psia를 분기점으로 연소속도가 급격히 증가되며, 압력지수는 0.4에서 약 0.8로 2배 이상 증가된다. 실제 모터의 연소시험에서 압력 상승률이 일반 압력(2000 psia)에서 작동하는 모터보다 300배 이상이 되며, 연소속도는 압력 상승률에 매우 민감하며 5-50배의 연소속도 증가를 나타낸다. 본 연구에서 제시된 압력 상승률을 감안한 연소속도 모델의 결과는 초고압에서 작동하는 실제의 다양한 조건에서 실시된 시험 데이터와 일치하는 결과를 제시하였다.

• 한국자동차공학회논문집
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• 제12권2호
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• pp.17-23
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• 2004

A cylindrical constant volume combustion bomb is used to investigate the combustion characteristics and to analyze the heat quantity of homogeneous charge methane-air mixture under various initial pressures, excess air ratios and ignition times. As the overall pressure increase, the values of maximum combustion pressure, maximum heat release rate and cumulative heat release have been increased. But it is not very meaningful to compare with some values such as maximum combustion pressure, maximum heat release rate and cumulative heat release for different overall pressure due to the different heat energy of supplied fuel. So the each value is needed to be compared with normalized value, which is divided by the entered fuel energy. To analyze the heat quantity, some definitions including the CHR ratio, the UHC ratio and the HL ratio are needed and are calculated. As the overall pressure increase, the CHR ratios and the UHC ratios have been decreased, while the HL ratios have been increased. The CHR ratio of 300 ms has the higher value than that of 10000ms, and the HL ratios of 300 ms have a lower value.