• Title/Summary/Keyword: Flammability

Search Result 247, Processing Time 0.028 seconds

The Prediction of Lower Flash Points by Optimization Method

  • Ha, Dong-Myeong;Lee, Sung-Jin
    • International Journal of Safety
    • /
    • v.8 no.2
    • /
    • pp.15-19
    • /
    • 2009
  • The flash point is the most widely used flammability property for the evaluation of the flammability hazard of combustible liquid mixtures. In this paper, the reported flash points for the the binary systems, ethylbenzene+n-butanol and ethylbenzene+n-hexanol were correlated by the optimization method. The optimization method based on the van Laar and Wilson equations were compared with the Raoult's law. The calculated values based on the optimization method were found to be better than those based on the Raoult's law.

A Prediction on the Flammability Limits of Biodiesel Fuel in the High Temperature and Pressure Conditions (고온·고압 조건에서 바이오디젤의 가연한계 예측)

  • Lim, Young Chan;Jung, Jun Woo;Suh, Hyun Kyu
    • Journal of ILASS-Korea
    • /
    • v.24 no.4
    • /
    • pp.157-162
    • /
    • 2019
  • This numerical study was analyzed to predict the flammability limits of biodiesel and diesel fuels in the high temperature and pressure conditions. To achieve this, the biodiesel fuel was simulated with the chemical species of n-heptane (n-C7H16), methyl decanoate (C11H22O2), and methyl-9-decenoate (C11H20O2), and the diesel fuel was substituted the chemical species of n-heptane. The closed 0-D homogeneous reactor model which was employed the 1100 K of ambient temperature and 35 atm of ambient pressure was used for the simulation of constant volume combustion, and the equivalence ratio was changed from 0.3 to 2.5 conditions. In addition, a comparative analysis study was conducted with the results of HCCI engine simulation and flammability limits according to the changes of equivalence ratio. The results of combustion temperature, pressure, and ignition delay were increased when the equivalence ratio elevated from 0.3 to 1.3 conditions because the increase in fuel oxidation rate affects the chemical reaction of the overall combustion process. Furthermore, the CO and NOX production under the rich combustion conditions are considered to have a trade off relationship since the OH radicals and O2 chemical species are greatly affected the CO and NOX production and oxidation processes.

Fire test procedures for flammability of bulkhead, ceiling and deck finish materials (선박의 격벽, 천정, 내장재 및 표면바닥재의 화재안정성 평가방법)

  • Kim, S.Y.;Kim, D.S.;Ahn, B.H.;Kwark, J.H.
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
    • /
    • 2008.04a
    • /
    • pp.117-119
    • /
    • 2008
  • It is very important to protect life, property at sea from any fire. Recommendation on improved fire test procedures for surface flammability of bulkhead, ceiling and deck finish materials specifies a procedure for measuring fire characterizing their flammability and thus their suitability for use in marine construction. In this paper, we investigated the positive expected by fire test procedures for flammability of bulkhead, ceiling and deck finish materials. Also, unusual materials were analyzed. Finally, we suggest methods to solve several problems related to unusual materials.

  • PDF

Flammability and Thermal Stabilities of Heat Transfer Oils (열매체유의 인화성과 열안정성)

  • Lee, Keun-Won;Lee, Jung-Suk;Choi, Yi-Rac
    • Journal of the Korean Institute of Gas
    • /
    • v.15 no.2
    • /
    • pp.82-87
    • /
    • 2011
  • Heat transfer oils are used in applications such as heating systems of chemical plant, refinery heat exchange systems, gas plant process, injection molding systems, and pulp and paper processing. These oils are extremely stable and resistance to thermal and oxidative degradation. In the event of a spill or accidental release of heat transfer oils, it can be ignite easily when there is an ignition source. This paper discusses the flammability and thermal stabilities of new and used oils. The flammability of the oils are assessed by measuring changes in flash point and auto ignition temperature. The thermal stability of oils are evaluated by the thermal screening unit ($TS^u$) and the differential scanning calorimeter (DSC). From the experimental results, it is suggested to give fire hazard characteristics to safe precautions for the proper use and treatment of heat transfer oils.

Effects of the Recess and Propellants Mass Flow on the Flammability Limit and Structure of Methane-Oxygen Diffusion Flame (인젝터 리세스와 추진제 공급유량이 메탄-산소 확산화염의 가연한계와 구조에 미치는 영향)

  • Hong, Joon Yeol;Bae, Seong Hun;Kim, Jeong Soo
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.22 no.1
    • /
    • pp.28-35
    • /
    • 2018
  • In order to analyze the flammability limit and structure of the gaseous methane-gaseous oxygen diffusion flame formed through a shear coaxial injector, combustion experiments were carried out according to the condition of injector recess and propellant mass-flow rate. As a result, it was confirmed that stable anchored flame was observed even at the high oxygen Reynolds number as the propellant momentum flux ratio increased, and that the recess had no significant influence on the flame shape and flammability limit. The anchored flame visualized through a chemiluminescence showed the maximum OH radical emission intensity at a specific position, irrespective of the propellant injection condition, and the radical intensity was greatly reduced by the injector recess.

The Effects of CIF$_3$and F$_2$on the Flammability Limit of H$_2$ (H$_2$의 연소한계에 미치는 F$_2$와 CIF$_3$의 영향)

  • ;H.Ohtani;Y.Uehara
    • Journal of the Korean Society of Safety
    • /
    • v.9 no.3
    • /
    • pp.53-59
    • /
    • 1994
  • Hydrogen(H$_2$) is used in the semiconductor industries, and some oxidizing gases such as fluoride(F$_2$) and chlorine trifluoride(CIF$_3$) are also used. As F$_2$and CIF$_3$are highly oxidizing gases, it were supposed to react vigorously with H$_2$. In this study, the flammability limit of F$_2$/$H_2$/Ar and CIF$_3$/$H_2$/Ar mixtures were investigated experimentally. As a result, it was found that the diluted F$_2$gas could be spontaneously ignited as compared to CIF$_3$mixture gas while being mixed with the diluted H$_2$gas. However, CIF$_3$diluted gas was not able to ignite spontaneously except for an electric spark. And the combustion characteristics and reaction kinetics were shown at the different diluted gases by the flammability diagram analyses between the F$_2$/$H_2$/Ar and CIF$_3$/$H_2$/Ar.

  • PDF

Synthesis and Flame - Retardant Optimization of Polyurethane Coatings Containing Trichloro Aromatic Modified Polyesters (트리클로로 방향족 변성폴리에스테르를 함유한 폴리우레탄 난연도료의 합성과 난연최적화)

  • Hwang, Kyu-Hyun;Kim, Dae-Won;Hahm, Hyun-Sik;Park, Hong-Soo
    • Journal of the Korean Applied Science and Technology
    • /
    • v.17 no.4
    • /
    • pp.240-247
    • /
    • 2000
  • Two-component polyurethane flame-retardant coatings were prepared by blending trichloro aromatic modified polyesters(TCMPs) and polyisocyanate. TCMPs were synthesized by polycondensation of trichlorobenzoic acid(TCBA), a flame-retardant component, with adipic acid, 1,4-butanediol, and trimethylolpropane. The content of TCBA was varied in 10, 20, and 30 wt% for the reaction. These new flame-retardant coatings showed various properties comparable to other non-flame-retardant coatings. Moreover, we carried out the combustion test and the flammability test for our flame-retardant coatings. The results of vertical burning test for the coatings containing more than 20 wt% of TCBA were determined as 'no burn'. The results of flammability test for the coatings with 20 wt% and 30 wt% of TCBA contents indicated the limiting oxygen index(LOI) values of 25% and 28% respectively, which implied relatively good flame retardancy.

Synthesis and Flame Retardant Improvement of PU Coatings Containing Trichloro Modified Polyester/IPDI-Isocyanurate

  • Kim, Ji-Hyun;Keun, Jang-Hyoun;Jung, Choong-Ho;Kim, Seung-Jin;Kim, Young-Geun;Kim, Seong-Kil;Park, Hong-Soo
    • Journal of the Korean Applied Science and Technology
    • /
    • v.25 no.3
    • /
    • pp.332-340
    • /
    • 2008
  • Two component polyurethane (PU) flame retardant coatings were prepared by blending trichloro modified polyesters (TCMPs) and isophorone diisocyanate isocyanurate. TCMPs were synthesized by polycondensation of trichlorobenzoic acid (TCBA), a flame retardant component, with adipic acid, 1,4 butanediol, and trimethylolpropane. The content of TCBA was varied in 10, 20, and 30 wt% for the reaction. Theses new flame retardant coatings showed various properties comparable to other non flame retardant coatings. Moreover, we carried out the combustion test and the flammability test for our flame retardant coatings. The results of vertical burning test for the coatings containing more than 20 wt% of TCBA were determined as no burn. The results of flammability test for the coatings with 20 wt% and 30 wt% of TCBA contents indicated the limiting oxygen index (LOI) values of 26% and 29% respectively, which implied relatively good flame retardancy.

Stabilization of Inert-Gas-Diluted Co-Flow Diffusion Flame by a Pilot Flame (불활성기체로 희석된 동축류 확산화염의 파일럿화염에 의한 안정화)

  • Ahn, Taekook;Lee, Wonnam;Park, Sunho
    • Journal of the Korean Society of Combustion
    • /
    • v.20 no.4
    • /
    • pp.19-25
    • /
    • 2015
  • An experimental study was conducted to find the effect of a pilot flame on the flammability of inert-gas-diluted methane and propane. The diffusion pilot flame was formed with propane at the innermost nozzle of a concentric triple co-flow burner. The main diffusion flame was formed with nitrogen-diluted methane or propane at the outermost nozzle of the burner. An air flow was located in-between. The results showed that the existence of the pilot flame helped stabilizing the main flame even at the flammability limit concentration of nitrogen-diluted fuel. The co-flow burner generated re-circulation zones and local variation of equivalence ratio depending on the flow rates of the reactants, which are known to help flame stabilization. Hot-wire experiments confirmed that both heating of the reactants and supplying of active chemical species by the pilot flame contributed to stabilization of the main flame. The results of this study would suggest a design concept for an efficient SVRU system that minimizes the emission of unburned hydrocarbon fuel from ship fuel tanks.

A flammability limit model for hydrogen-air-diluent mixtures based on heat transfer characteristics in flame propagation

  • Jeon, Joongoo;Choi, Wonjun;Kim, Sung Joong
    • Nuclear Engineering and Technology
    • /
    • v.51 no.7
    • /
    • pp.1749-1757
    • /
    • 2019
  • Predicting lower flammability limits (LFL) of hydrogen has become an ever-important task for safety of nuclear industry. While numerous experimental studies have been conducted, LFL results applicable for the harsh environment are still lack of information. Our aim is to develop a calculated non-adiabatic flame temperature (CNAFT) model to better predict LFL of hydrogen mixtures in nuclear power plant. The developed model is unique for incorporating radiative heat loss during flame propagation using the CNAFT coefficient derived through previous studies of flame propagation. Our new model is more consistent with the experimental results for various mixtures compared to the previous model, which relied on calculated adiabatic flame temperature (CAFT) to predict the LFL without any consideration of heat loss. Limitation of the previous model could be explained clearly based on the CNAFT coefficient magnitude. The prediction accuracy for hydrogen mixtures at elevated initial temperatures and high helium content was improved substantially. The model reliability was confirmed for $H_2-air$ mixtures up to $300^{\circ}C$ and $H_2-air-He$ mixtures up to 50 vol % helium concentration. Therefore, the CNAFT model developed based on radiation heat loss is expected as the practical method for predicting LFL in hydrogen risk analysis.