• 한국철도학회논문집
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• 제7권3호
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• pp.180-185
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• 2004

The present study investigates the effect of fire growth model on fire development characteristics in a carriage. The parallel processing version of FDS code is used to simulate the fire driven flow in a carriage and two types of fire growth model which are flame spread model and t$^2$ model are examined for the same geometrical condition. The heat release rates(HRR) of both model are similar each other until 30 s after ignition, but the flame spread model predicts 5 times higher than those of the t$^2$ fire model during the quasi-steady fire period. Maximum heat release rate in the case of flame spread model reaches about to 12 MW at 100 s after fire ignition. Also, various database of fire properties for combustible materials and more elaborate combustion model considering the flame spreading phenomena are required for better predictions of fire development characteristics using numerical simulation.

• 에너지공학
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• 제23권1호
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• pp.75-80
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• 2014

지난 최근 몇 년 동안 내연기관 엔진의 여러 가지 타입의 성능, 효율, 배기가스 특성을 잘 설명해 줄 수 있는 흥미있는 수학적인 모델이 다양하게 제시되고 있다. 이러한 다양한 양상의 엔진 작동의 모의실험에 있어서 주요한 요소가 엔진 연소 과정의 모델이다. 연소모델은 주로 세 가지 분류로 세분화 되어지고 있다. 즉, 제로 차원적, 유사 차원적, 다차원 모델로 나눌 수 있다. 제로 차원모델은 열역학 제1법칙에 근거하여 만들어졌고, 시간은 단지 독립 변수이다. 본 연구는 제로 차원 모델에 의하여 스파크 점화 기관의 연소 특성을 제시하려는 그 목적이 있다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.119-120
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• 2014

In this study, we looked into the method to establish fire growth rate by buildings use for growing fire at the beginning of a fire considering the characteristics of the combustibles in a performance-based design. Actual conditions survey and literature review were carried out for the fire load and exposed surface area of combustibles to establish design fire by domestic building use. As a results, a simplified prediction equation of fire growth rate which depends on fire load and weight of combustibles could be derived by calculating the relation between the fire load and the fire growth rate of an initial fire through investigation of combustibles by domestic building use.Also, as a result of analyzing the placement of combustibles and location of the ignition source, it was found that the influence of the materials of the combustibles and the materials of the combustibles adjacent to the ignition source is big. Though 4 different experiments were carried out for the evaluation, the result of comparing the findings with those of FGR model showed that the fire growth rate was similarly derived.

• 한국추진공학회지
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• 제16권5호
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• pp.47-57
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• 2012

고에너지 물질의 연소 현상을 해석하기 위하여 반드시 필요한 반응속도식과 이를 구성하고 있는 미 정상수를 결정하는 이론적 방법을 제안하였다. 개선된 I&G 모델은 기존의 반응속도식이 갖던 문제점들을 효과적으로 극복하면서 동시에 중요한 물리적 의미를 내포하는 형태로 제안되었다. 이는 공극붕괴(void collapse)로 인한 hotspot의 생성을 의미하는 점화 모델과 폭굉(detonation)으로의 천이를 의미하는 화염 발달 모델의 합으로 구성되어 있다. 또한 함께 소개된 이론적 모델은 고에너지 물질의 수치해석 기법인 Hydrocode를 사용하기 전에 미정상수 $b,\;G,\;x,\;I$를 결정함으로써 특정 고에너지 물질의 연소 특성을 규명하는데 사용된다. 이론적 방법은 기존의 고에너지 물질의 연소 시험을 모사한 수치해석적 방식보다 효율적이고 정확도가 높은 결과를 제공하므로 진일보 된 방법이라고 할 수 있다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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• pp.331-341
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• 2012

고에너지 물질의 연소 현상을 해석하기 위하여 반드시 필요한 반응속도식과 이를 구성하고 있는 미정상수를 결정하는 이론적 방법을 제안하였다. 개선된 I&G 모델은 기존의 반응속도식이 갖던 문제점들을 효과적으로 극복하면서 동시에 중요한 물리적 의미를 내포하는 형태로 제안되었다. 이는 공극붕괴(void collapse)로 인한 hotspot의 생성을 의미하는 점화 모델과 폭굉(detonation)으로의 천이를 의미하는 화염 발달 모델의 합으로 구성되어 있다. 또한 함께 소개된 이론적 모델은 고에너지 물질의 수치해석 기법인 Hydrocode를 사용하기 전에 미정상수 b, G, x, I를 결정함으로써 특정 고에너지 물질의 연소 특성을 규명하는데 사용된다. 이론적 방법은 기존의 고에너지 물질의 연소 시험을 모사한 수치해석적 방식보다 효율적이고 정확도가 높은 결과를 제공하므로 진일보 된 방법이라고 할 수 있다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제45회 KOSCO SYMPOSIUM 초록집
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• pp.97-99
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• 2012

A pressure-based BOIK model considering Shock to Detonation Transition(SDT) and damage due to external fragment or bullet stimuli impact on energetic materials and analytical approach for determination of free parameters are proposed. The rate of product mass fraction(${\lambda}$) consists of ignition term that represents the initiation due to shock compression and growth term that describes propagation of detonation wave and strain term representing the morphological deformation induced by external impact.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.193-200
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• 1997

Flame spread and heat release properties and incident heat flux of interior materials subject to an igniter heat flux in a compartment are investigated and compared by using computer model. A comer fire ignition source is maintained for 10 minutes at 100 kw and subsequently increased to 300kw. In executing the model, base-line material properties are selected and one is changed for each run. Also 4 different igniter heat flux conditions and examined. Results are compared for the 12 different materials tested by the ISO Room Comer Test (9705). The time for total energy release rate to reach 1MW is examined. The parameters considered include flame heat flux and thermal inertia, lateral flame spread parameter, heat of combustion and effective heat of gasfication. The model can show the importance of each property in causing fire growth on interior Hnish materials in a compartment. The effect of ignitor heat flux and material property effects were demonstrated by using dimensionless parameters a, b and Tb. Results show that for b greater than about zero, flashover time in the ISO Room-Corner test is principally proportional to ignition time and nothing more.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2149-2153
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• 2008

A large-scale fire test was done for interior materials from a vehicle installed within a fire test room. The interior materials are satisfied with the Korean guide for the safety of rail vehicle. The guide has taken effect since December 2004 in Korea. Ignition source (gas burner) was increased in several controlled steps. The objectives of this test are to assess the fire performance in terms of ignition and flame spread on interior lining materials and to provide data on an enclosure fires involving train interior materials that grow to flashover. This data will be used to develop and calibrate an Fire Dynamics Simulator (FDS) model for fire growth on the interior vehicle.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.590-595
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• 2008

A large-scale fire test was done for interior materials from a vehicle installed within a fire test room. The interior materials are the old style before interior replacement by the Korean guideline for the safety of rail vehicle. Ignition source (gas burner) was increased in several controlled steps. The objectives of this test are to assess the fire performance in terms of ignition and flame spread on interior lining materials and to provide data on an enclosure fires involving train interior materials that grow to flashover. This data will be used to develop and calibrate an Fire Dynamics Simulator (FDS) model for fire growth on the interior vehicle.

• 한국자동차공학회논문집
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• 제7권8호
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• pp.24-33
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• 1999

This paper investigate the effects of the variations of engine operation condition in the flame kernel formation and developmnet . A model for calculating the initial kernel development in spark ignition engines is formualted. It considered input of electrical energy, combustion energy release and heat transfer to the spark plyg, cylinder head, and unburned mixture. The model also takes into accounts strain rate of initial kernel and residual gas fraction. The breakdown process and the subsequent electrical power input initially control the kernel growth while intermediate growth is mainly dominated by diffusion or conduction. Then, the flame propagates by the chemical energy and turbulent flame expansion. Flame kernel development also influenced by engine operating conditions, for example, EGR rate, air-fuel ration and intake manifold pressure.