• Title/Summary/Keyword: Flame temperature

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Comparative study of experimental equations on measurement of fire hight on pool fire (Pool fire에서의 화염의 높이 계산에 관한 실험식의 비교연구)

  • Hwang, Woon-Gi;Kwon, Chang-Hee
    • Journal of the Korea Safety Management & Science
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    • v.19 no.1
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    • pp.9-13
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    • 2017
  • In this study, the height of the flame required to estimate the heat flow path and flame spread in pool fire has been applied by the empirical formula, but it is calculated without applying the pressure and temperature parameters of the fire room. Until now, the height of the flame applied to pool fire was $l_F=0.235Q^{2/5}-1.02D$ in the Heskestad empirical formula, but accurate temperature calculation was not possible due to the temperature and pressure which are not influenced by the flame height. Therefore, applying the temperature and pressure around it can calculate the exact flame height, which can be applied to fire investigation and fire dynamics. The structure of the flame is divided into a continuous flame, an intermittent flame, and a buoyancy flame, but it is assumed that the flame height is calculated from the visual aspect to the intermittent flame region, and the temperature of the buoyancy flame is very low. The effect of heat of vaporization on the height of flame was investigated. The results showed that flame height was different according to the pressure and temperature around the fire room.

Soot Concentration and Temperature Measurements in Laminar Ethylene Jet Double-concentric Diffusion Flames (동축 이중 에틸렌 확산화염의 매연 농도분포 및 온도 측정)

  • Lee, Gyo-U;Jeong, Jong-Su;Hwang, Jeong-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.3
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    • pp.402-409
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    • 2002
  • Experiments were performed with double-concentric diffusion flame(DDF) in order to investigate the characteristics of soot formation and temperature distributions. The flame size and shape of the DDF are similar to those of the well-known normal co-flow diffusion flame(WF), except the formation of a tiny inverse flame near the central tube exit. A laser light extinction technique was used to measure the soot volume fractions. The temperature distributions in the flame were measured by rapid insertion of a R-type thermocouple. Soot concentrations along the flame axis of the DDF were higher than those of the NDF. However, the maximum soot volume fraction of the DDF along the periphery of the flame was lower than that of the NDF. It is mainly due to the effect of nitrogen-dilution from the inner air. Measured temperature distribution explains these trends of soot concentration. The temperature along the flame axis was also higher in DDF than that of the NDF. However, the flame temperatures at the flame front of the two flames were almost same regardless of the inner flame. This phenomenon means that the inverse flame inside the DDF did not affect on the flame structure including the temperature and soot concentration, except the region around the flame axis.

Effect of Oxygen-Enriched Flame Temperature on the Crystalline Structures of the Flame-Synthesized TiO2 Nanoparticles (산소부화를 통한 화염온도 변화에 따른 연소합성된 TiO2 나노입자의 결정구조 변화)

  • Lee Gyo-Woo
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.30 no.7 s.250
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    • pp.692-699
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    • 2006
  • In this work, $TiO_2$ nanoparticles were synthesized using $N_2-diluted$ and Oxygen-enriched co-flow hydrogen diffusion flames. The effect of flame temperature on the crystalline structure of the formed $TiO_2$ nanoparticles was investigated. The measured maximum centerline temperature of the flame ranged from 2,103k for oxygen-enriched flame to 1,339K for $N_2-diluted$ flame. The visible flame length and the height of the main reaction zone were characterized by direct photographs. The crystalline structures of $TiO_2$ nanoparticles were analyzed by XRD. From the XRD analysis, it was evident that the crystalline structures of the formed nanoparticles were divided into two sorts. In the higher temperature region, over the 1,700K, the fraction of formed $TiO_2$ nanoparticles having anatase-phase crystalline structure increased with increasing the flame temperature. On the contrary, in the lower temperature region, below the 1,600K, the fraction of anatase-phase nanoparticles increased with decreasing the flame temperature.

Measurement of Soot and Temperature on Bio Diesel Flame by Two-Color Method (이색법에 의한 바이오 디젤화염의 그을음과 온도 측정)

  • Kim, M.S.;Kang, H.Y.
    • Journal of Power System Engineering
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    • v.16 no.4
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    • pp.5-11
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    • 2012
  • There were some papers for diesel engine performance tests using BDF, but few article deals with the temperature and soot concentration of Bio diesel flame. Since the flame temperature of diesel engines is so high and change rapidly, an optical method for measurement of flame temperature is known as the most effective one. The two-color method regarding the visible wavelength radiation for the soot particles in flame was applied on Bio diesel flame in order to measure flame temperature and soot concentration in a diesel engine. Photo detecting device was newly designed and employed TSL250R, photo-diode, to pick-up the light information emitted from the combustion flame. As a result, real flame temperature T, as a flame brightness temperature, through Ta1, Ta2, were obtained and finally the characteristics of KL value as a soot concentration reveal the difference of combustion information between diesel fuel, blending oil and Bio diesel fuel oil.

Effects of Flame Temperature on the Characteristics of Flame Synthesized $TiO_{2}$ Nanoparticles (화염온도에 따른 $TiO_{2}$ 나노입자의 결정구조 및 입자크기 변화)

  • Lee, Gyo-Woo;Jurng, Jong-Soo;Bae, Gwi-Nam
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.1347-1352
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    • 2004
  • In this work, $TiO_{2}$ nanoparticles were synthesized using a $N_{2}-diluted$ hydrogen coflow diffusion flame. The effect of flame temperature on the crystalline structure and the size of formed nanoparticles was investigated. The maximum centerline temperature of the flame ranged from 1,920K for $H_{2}-only$ flame to 863K for 81% $N_{2}-diluted$ flame. When the temperature was higher than about 1,000K, the particle size was tend to increase due to the agglomeration and sintering among the primary particles. On the other hand, when the temperature was lower than 1,000K, the portion of anatase phase was greater than 80%.

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A Study on the Flame Temperature Measurement of the Transiently Propagating Flame by using Platinum-Hot-Wire-Resistance-Thermometry (열선백금저항선을 이용한 과도적 전파화염의 화염온도측정에 관한 연구)

  • 정인석;조경국;황상순
    • Journal of the korean Society of Automotive Engineers
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    • v.7 no.3
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    • pp.94-101
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    • 1985
  • The flame temperature of LPG-air premixture flame was measured by extrapolation of limiting case corresponding to the infinitely thin diameter of Platinum-resistance-hot-wire. LPG-air premixture flame, initially under atmospheric pressure and room temperature, propagates downward from top of the model combustion chamber maintained at constant pressure through the whole combustion process. Analytical calculation technique was also applied to determine full temperature history or spatial temperature distribution from flame reaction zone to burnt gas region.

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Effect of Flame Temperature on the Characteristics of the Combustion Synthesized $TiO_2$ Nanoparticles (연소합성된 $TiO_2$ 나노입자의 입자특성에 대한 화염온도 변화의 영향)

  • Lee, Gyo-Woo
    • Journal of the Korean Society of Combustion
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    • v.11 no.1
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    • pp.11-18
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    • 2006
  • In this work, $TiO_2$ nanoparticles were synthesized using $N_2-diluted$ and Oxygen-enriched coflow hydrogen diffusion flames. The effect of flame temperature on the characteristics of the formed $TiO_2$ nanoparticles was investigated. The measured maximum centerline temperature of the flame ranged from 2,103 K for oxygen-enriched flame to 1,339 K for $N_2-diluted$ flame. The visible flame length and the height of the main reaction zone were characterized by direct photographs. The characteristics of synthesized $TiO_2$ nanoparticles were analyzed by SEM and TEM images. From these images, it was evident that the formed nanoparticles were divided into two sorts. In the higher temperature region, over the 1,700 K, $TiO_2$ nanoparticles having spherical shapes with diameters about 60 nm were synthesized. In the lower temperature region, below the 1,600 K, the diameters of formed nanoparticles having unclear boundaries were ranged from 35 - 50 nm.

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A Study on In-Cylinder Measurement of Flame Temperature and Soot Distribution in D.I. Diesel Engine Using Tow-Color Method (이색법을 이용한 직접 분사식 디젤엔진 실린더내의 화염 분도 및 Soot 분포 측정에 관한 연구)

  • 박정규;정수훈;원영호
    • Transactions of the Korean Society of Automotive Engineers
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    • v.7 no.7
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    • pp.42-53
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    • 1999
  • Two dimensional flame temperature and KL value distribution from the luminous flame containing soot in a DI diesel engine were measured by the tow-color method using tow different wavelengths of the flame image. The combustion chamber of a DI diesel engine was visualized by elongating the piston and cylinder and the flame in the combustion chamber was photographed on a nega-color film using a high speed camera. In this study, color CCD camera was used to digitize the three color density of the film exposed to the flame and standard lamp . The accuracy of the measuring method depends on the calibration line of film made from a high temperature standard tungsten lamp. The formation and oxidization of soot in the diesel engine were studied by observing measured time history of KL factor and flame temperature . Also , effects of various shapes of combustion chamber and fuel injection on flame temperature. Also, effects of various shapes of combustion chamber and fuel injection on flame temperature and KL value distribution were examined.

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Studies on the Flame Temperature Measurement of the Propagating Flame (전파화염에서의 화염온도측정에 관한 연구)

  • ;;Jeung, In Seuck
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.1 no.4
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    • pp.182-189
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    • 1977
  • The propagating flame temperature of the Propane-Air premixture by using 30.$\mu$ and 50.$\mu$ diameter platinum sensing wires, that is, Two Wires Correction Method, Through the constant volume burining inside the 150mm diameter, 30mm height combustion chamber under the circumstances of the atomospheric pressure, and the room temperature was determined. Also the temperature distribution across High Temperature Region, i.e. Flame Front, and the temperature profile behind the flame the front have been obtained.

Experimental Study on the Effect of a Metal Storage Cask and Openings on Flame Temperature in a Compartment Fire

  • Bang, Kyoung-Sik
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.18 no.3
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    • pp.395-405
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    • 2020
  • Compartment fire tests were performed using kerosene and Jet A-1 as fire sources to evaluate the relationship between flame temperature and opening size. The tests were performed for a fire caused by the release of kerosene owing to vehicle impact, and for a fire caused by the release of Jet-A-1 owing to airplane collision. The compartment fire tests were performed using a 1/3-scale model of a metal storage cask when the flame temperature was deemed to be the highest. We found the combustion time of Jet-A-1 to be shorter than that of kerosene, and consequently, the flame temperature of Jet-A-1 was measured to be higher than that of kerosene. When the opening was installed on the compartment roof, even though the area of the opening was small, the ventilation factor was large, resulting in a high flame temperature and long combustion. Therefore, the position of the opening is a crucial factor that affects the flame temperature. When the metal storage cask was stored in the compartment, the flame temperature decreased proportionally with the energy that the metal storage cask received from the flame.