축소 모의된 구획 화재의 흘림 실험에 대한 인화성 액체의 화재 패턴 해석

조희수,최충석 한국화재소방학회 2014 한국화재소방학회논문지 Vol.28 No.3

The purpose of this study is to analyze the flame propagation speed, radiation range, diffusion pattern and combustioncompletion time of a fire by filling a divided space with single combustible substance. It was found that the flame propagationspeed was the fastest (0.2 s) for kerosene and the lowest (82.1 s) for alcohol. In the case of paint thinner, it took19.0 s for the flame to reach its peak at the fastest speed after ignition while in the case of alcohol, it took 138.6 s for theflame to reach its peak at the lowest speed. In the case of the combustion of 200 ml of flammable liquids, the combustioncompletion time was 79.9 s for paint thinner, which is the shortest, 135 s for gasoline, 170 s for kerosene, 231.4 s for dieseland 337.0 s for alcohol. In addition, when flammable liquids are combusted, the lower part of the flame is governed bylaminar flow pattern and the upper part of the flame showed turbulence pattern. In the case of a test performed for beanoil, it could be seen that if the fire source was removed, the flame was automatically extinguished without further combustionand that white smoke was generated due to incomplete combustion. 본 연구는 구획된 공간에 인화성 단일 물질을 채우고 착화된 화염의 전파 속도, 방사 범위, 확산 패턴 및 연소 완료시간 등을 해석하는 데 있다. 화염의 전파 속도는 등유가 0.2 s로 가장 빠르고, 알코올이 82.1 s로 가장 늦었다. 화염이착화된 후 화염이 가장 빠르게 최성기에 도달한 것은 시너이었고 19.0 s가 걸렸다. 그리고 가장 늦은 것은 알코올로138.6 s로 측정되었다. 인화성 액체 200 ml가 연소 완료되는 시간은 시너가 79.9 s로 가장 짧았고, 가솔린 135 s, 등유170 s, 경유 231.4 s, 알코올 337.0 s 등으로 측정되었다. 그리고 인화성 액체가 연소될 때 화염의 하단 부분은 층류 패턴이 지배하였고, 상단 부분은 난류 패턴을 나타냈다. 대두유의 실험에서 착화시킨 화원을 제거하면 화염은 자연 소화되어 연소가 진행되지 않았고, 불완전 연소에 따른 흰색의 연기가 발생하는 것을 알 수 있었다.

니들 플레임에 의한 바닥재의 수직 연소 및 탄화 패턴의 해석에 관한 연구

박민수,최충석 한국화재소방학회 2020 한국화재소방학회논문지 Vol.34 No.4

This study analyzed flame growth characteristics and carbonization patterns when floor materials were burned verticallyusing a needle flame produced for this study. It was found that PVC flooring was fire retardant and the area under directflame contracted inward. Vertical combustion causes solidification in the form of a lump at the bottom and also generatessoot in a pattern that progresses upwards. This study found that laminated flooring exhibited no fire retarding characteristicsand that the laminated layer of its upper surface was destroyed by fire, causing irregular delamination. The carbonizationranges at the left and right sides were determined to be symmetrical. A vertical combustion test of a sample carpet showedthat it exhibited no fire-retarding characteristics. It was observed that if heat accumulated in the carpet, the flame formedan ascending air current, and that when flammable materials were present around the flame, they further accelerated thediffusion of the flame. The carbonization pattern at the carpet surface exposed to direct flame revealed that the carpetsurface had melted and had flown downwards and that many tiny holes formed on it. 자체 제작된 니들 플레임을 이용하여 바닥재를 수직 연소시켰을 때의 화염의 성장 특성 및 탄화 패턴을 해석하였다. PVC 장판은 난연성이 있는 것으로 확인되었고, 직사 화염을 받은 곳은 안쪽으로 수축되는 패턴을 나타냈다. 수직 연소가 진행되면 하부에 망울 형태의 고형화가 발생하며, 그을음은 상부로 성장하는 패턴이 형성된다. 강화마루는 난연성이 없는 것으로 확인되었으며, 상부 표면인 라미네이트층의 소실과 불규칙적인 박리가 형성되는 것을 알수 있다. 좌측면과 우측면의 탄화의 범위는 대칭적 구조를 나타내는 것으로 해석된다. 강화마루와 마찬가지로 카펫은 수직 연소 실험에서 난연성이 없는 것이 확인되었다. 카펫에 축열이 형성되면 화염은 상승기류를 형성하고, 주변에 가연성 물질이 있을 때 화염의 확산은 더욱 촉진하는 것을 알 수 있었다. 직사화염을 받은 카펫 표면의 탄화 패턴은 표면이 용융되어 흘러내렸을 뿐만 아니라 작은 구멍이 다수 발생되는 것을 알 수 있다.

저압 분전반의 화염에 의한 소손패턴 분석

김동욱(Kim, Dong-Ook),이기연(Lee, Ki-Yeon),김동우(Kim, Dong-Woo),길형준(Gil, Hyoung-Jun),김향곤(Kim, Hyang-Kon) 한국화재소방학회 2008 한국화재소방학회 학술대회 논문집 Vol.2008 No.춘계

This paper deals with damage patterns of cabinet panel for low voltage deteriorated by flame. In order to analyze damage patterns, we used Metallurgical Microscope, x-ray system, and Fourier Transform Infrared spectroscopy. Firstly, Metallurgical microscope was used for analysis of electrical causes, such as electric short and overload. Secondly, X-ray system was used for analysis of internal characteristics of circuit breakers. Lastly, Fourier Transform Infrared spectroscopy was used for analysis of damage direction by flame. The following results were obtained.

분전반의 화염에 의한 소손패턴 분석

김동욱,이기연,김향곤,김만건,Kim, Dong-Ook,Lee, Ki-Yeon,Kim, Hyang-Kon,Kim, Man-Geon 한국화재조사학회 2008 한국화재조사학회 논문지 Vol.11 No.1

본 연구는 저압 분전함내에서 발생한 사고사례를 분석하여 사고의 메커니즘과 사고특성 등을 연구하여 사고 패턴을 제시함으로서 전기설비 사고 원인 분석 및 진단을 위한 자료를 확보하고자 하였다. 이를 위해 금속현미경, X-ray, FI-IR 등의 분석을 하였다. This paper deals with damage patterns of cabinet panel for low voltage deteriorated by flame. In order to analyze damage patterns, we used Metallurgical Microscope, x-ray system, and Fourier Transform Infrared spectroscopy. Firstly, Metallurgical microscope was used for analysis of electrical causes, such as electric short and overload Secondly, X-ray system was used for analysis of internal characteristics of circuit breakers. Lastly, Fourier Transform Infrared spectroscopy was used for analysis of damage direction by flame.

화재시 열가소성 필름의 Drop down patterns에 관한 연구

김용운,고재선 한국화재감식학회 2015 한국화재감식학회 학회지 Vol.6 No.4

On the basis of drop down patterns found in the scene of fire, a study on burn pattern was made through simulation with model, test of deformation due to radiant heat, and ignition test regarding an effect produced on the scene of fire. And the results of study led to the following conclusions. First, in the ignition test of thermoplastic film, it was possible to verify that trash bag and greenhouse film has the largest amount of debris and the fallen debris had kept reburning for a long period of time. Among test materials, wrap had a high burning rate, and instantaneously burned. And in case there was a combustible at the end of burning, it was possible to verify that burning could extend. Second, in the radiant heat test on the upper part [temperature 340℃(±5℃)] of heating element in electric stove, it was possible to verify that all of 3 types except wrap ignited and debris flew down. Third, it was possible to verify that radiant heat and convective heat formed the temperature which could ignite a thermoplastic film through FDS and full-scale model. And it was verified that convection current can ignite a thermoplastic film. As a result, it was possible to find that an independent ignition point occurred. In the future, the results of this study are expected to become small reference data in scene investigation. And it is to be hoped that the results of this study will provide an opportunity for fire station to win the public trust outside as a professional fire cause investigation organization, and to contribute to the improvement of credibility by the scientific determination of fire cause.

과열에 의해 발화된 동물성 식품의 화염 및 탄화 패턴에 관한 연구

이정훈,최충석 한국화재소방학회 2019 한국화재소방학회논문지 Vol.33 No.6

Real-scale fire tests were performed on animal-origin foods using a gas stove with no overheating prevention device. When the animal-origin foods were ignited, a large quantity of white smoke and steam was generated from them; however,when they became dry and began to carbonize, a dark smoke was generated. Even after the gas stove was overheated formore than 5400 s, mackerel, pollack, chicken, etc., did not ignite. However, pork, beef, and tuna caught fire after 2643 s,2819 s, and 6492 s of heating, respectively. The flame patterns of animal-origin foods were in the forms of a mixed laminarflow and a turbulent flow, and a halo pattern was produced. A sand glass form of the flame pattern was generated whena kitchen hood was operated, but a triangular flame pattern was produced when the kitchen hood was not operated. Whenthe tuna in the pot was overheated, it spontaneously ignited after 6492 s, with the surface temperature of the kitchen hoodrapidly rising to 464.5 ℃. Moreover, the temperature at the back of the pot, which was 6 cm away from the outer surfaceof the upper part of the pot, was 869 ℃ after 6660 s because of the radiant heat. The flame formed a sand glass patternon the kitchen wall. When the kitchen hood was not operated, or when the flame grew lower than the height of the ceiling,a triangular pattern was formed. 과열방지장치가 없는 가스레인지를 이용하여 동물성 식품의 실물 화재 실험을 실시하였다. 동물성 식품의 연소초기에는 흰색의 연기와 수증기가 다량 발생했으나 물기가 없어지고 동물성 식품의 탄화가 시작되면 검정색 연기가발생하였다. 가스레인지의 과열 시간이 5,400 s가 경과되어도 고등어, 명태 및 닭고기 등은 착화되지 못했다. 그러나돼지고기는 2,643 s, 쇠고기는 2,819 s, 참치는 6,492 s에서 발화되는 것을 확인하였다. 동물성 식품의 화염 패턴은 층류와 난류가 혼합된 형태이며, 달무리 패턴(Halo Pattern)이 발생하는 것을 알 수 있었다. 주방 후드가 작동할 때의화염은 모래시계 패턴을 형성하였고, 주방 후드가 작동하지 않을 때는 삼각형 패턴을 나타냈다. 냄비에 담긴 참치가과열되면 6,492 s에 자연발화 되었고, 주방 후드의 표면 온도는 464.5 ℃로 급격히 상승하였다. 그리고 냄비 상부의바깥 표면으로부터 6 cm 이격된 냄비 후면의 온도는 6,660 s에 복사열로 인해 869℃로 측정되었다. 화염에 의해 소손된 주방 벽면에는 모래시계 패턴이 형성되었으며, 주방 후드가 작동하지 않거나 천장 높이보다 화염이 작게 성장할때는 삼각형 패턴을 나타내는 것이 확인되었다.

조선후기 『산릉도감의궤(山陵都監儀軌)』 백호도(白虎圖) 연구

김종미(Kim, Jong-Mi) 역사문화연구소 2014 역사문화논총 Vol.- No.8

Since Baekho-do in Sanneungdogam-Uigwe drawn at a state funeral in the late Joseon Dynasty had a clear production era and was drawn by the best painters, it is significant data by which the directions of development of the late Joseon Dynasty paintings can be judged. This paper comprehensively looked into Baekho-do in Sanneungdogam-Uigwe in the late Joseon Dynasty to conduct an inquiry into the phase of its changes. Baekho-do in Sanneungdogam-Uigwe in the late Joseon Dynasty can be broadly classified into three types: ‘ Jingnipho’, ‘ Jwaho’ and ‘Chulsanho,’ which show six stages of the process of changes, that is, ‘Jingnipho A-type’, ‘Jwaho-type’, ‘Jingnipho B-type’, ‘Chulsanho A-type’, ‘Chulsanho B-type’ and ‘Chulsanho B′-type.’ The oldest Baekho-do, Wonjongyejang Baekho-do (1627) was drawn as Jingnipho in a diagonal line, which shows flame pattern and plumage. It shows that its tradition expressed as mystical creature and guardian since mural paintings of the Goguryeo ancient tombs had remained in the 17th century. Later, in Baekho-do in Injojangneung (1649), Jwaho-type Baekho-do without flame pattern and plumage was drawn, of which the body proportion is accurate and realistic. The mid-17th century is an important period when even Baekho-do guarding the space of the dead did not express flame pattern and plumage, but pursued realism. However, the 17th century seems to show a process of seeking for a model of Baekhodo: e.g. it turned back into Jingnipho with flame pattern drawn in 1674. Meanwhile, in Queen Inhyeon Baekho-do in the beginning of the 18th century (1701), Baekho-do in the form of Chulsanho drawn at the time in three countries in East Asia appeared for the first time. Queen Inhyeon Baekho-do (1701) shows the posture coming down the mountain, the curved body and shading between the toes, which are a step higher level of paintings; however, flame pattern appears, which shows the tradition of Sasin-do remained until this time. In Queen Jeongseong Baekho-do (1757), Baekho-do without flame pattern appeared. Finally, a model of Baekho-do in Sanneungdogam-Uigwe in the late Joseon Dynasty was established. This is a result of the reflection of ‘a realistic view of things,’ a characteristic of paintings in Jingyeong era. This period is a time with works that form the climax of Baekho-do: e.g. describing a streamlined flow to the end of the tail such as slender waist, strong lower body and swinging tail. Later, the tradition of tiger pictures in Joseon Dynasty declined: e.g. deepened formal expression in Baekho-do. Baekho-do in Sanneungdogam-Uigwe showing a change into Sasu-do in a form of a tiger in Sasin-do that expresses flame pattern and plumage is in the same vein with the change in the view of painting in the late Joseon Dynasty, which shows a constant change.

삼국시대 불상 광배 문양과 일본 비조시대(飛鳥時代) 불상 광배 문양의 관계성 고찰

고승희 ( Koh Seung-hee ) 한국불교미술사학회(한국미술사연구소) 2017 강좌미술사 Vol.48 No.-

본 연구는 우리나라 삼국시대와 일본 아스카시대 불상의 광배 문양을 통해서 삼국시대의 불교문화 양식이 일본에 어떠한 영향력을 미쳤는지에 대해 파악해 보고자하였다. 삼국 가운데 특히 백제의 불교문화는 577 년 건립한 국가적 대가람 왕흥사(王興寺) 목탑지에서도 확인할 수 있듯이 일본 고대문화의 형성에 지대한 영향을 미치게 되어 최초의 사원인 아스카데라(飛鳥寺) 건립에 중추적인 역할을 하고 불교문화 교류도 활발히 이루어졌던 것으로 주목되고 있다. 현재 법륭사에는 7 세기 조성의 금동불상과 목불상들이 전래되어 오고 있는데, 이 불상들은 우리나라 삼국시대, 특히 백제와 밀접한 관계를 갖고 성립되었다는 것은 이미 많은 국내 학자들의 연구를 통해 밝혀졌다. 따라서 아스카시대(飛鳥時代) 불교미술의 대표격이라고 할 수 있는 법륭사의 불교미술을 살펴보는 것은 역으로 우리나라 삼국시대 불교미술 연구에 반드시 필요한 과제가 되리라고 생각한다. 이런 중요성을 감안해서 이 글에서는 삼국시대 가운데 백제의 불상 광배(光背) 문양을 중심으로 전체적으로 살펴보고 일본 법륭사 금당에 봉안된 금동석가삼존불좌상의 광배 문양에 대해 세부적으로 살펴보고자 한다. 연구 결과 법륭사 금당 금동석가삼존불좌상의 광배 문양을 통해 일본서기의 기록대로 백제 불상조각 양식이 절대적인 영향을 끼쳤다는 사실을 입증할 수 있었으며, 또한 광배 뒷면의 명문을 통하여 이 상은 백제 출신인 도리불사(止利佛師)에 의해 조성되었다는 것도 확인되었다. 그리고 중국과 우리나라 고구려, 백제, 신라 등의 주형거신광과 일광삼존불 형식을 통해 법륭사 석가삼존불상과의 영향관계를 알아보고 광배에 시문된 연화문, 당초문, 화염문 등의 경우 백제시대 문양과 친연성이 있음을 볼 수 있었다. 본 연구는 비록 비교 대상이 법륭사 금당 봉안의 금동석가삼존불상으로 제한적이기는 하나 이렇듯 몇 가지 사실을 통해 법륭사가 창건된 시기의 불교미술과 우리나라 백제시대 6 세기 후반기-7 세기 초기 양식과 거의 흡사하다는 점을 밝혀보았으며, 삼국시대의 불상 전파 관계도 확인할 수 있었다는데 의의를 두고자 한다. This study tried to explore the influence of the Buddhist culture style of the Three Kingdoms period on Japan through the Halo patterns of Buddhist statues of the Three Kingdoms period in Korea and the Asuka period in Japan. Among the three kingdoms, Baekje`s Buddhist culture, as seen in the wooden pagoda site of Wangheungsa (王興寺), a great national Buddhist temple built in 577, greatly influenced the formation of Japan`s ancient culture, and played a pivotal role in constructing the first temple, the Asuka temple. And it has been noted that cultural exchanges of Buddhism were actively conducted between Baekje and Japan. At present, gilt bronze Buddhist statues and wooden Buddhist statues created in the 7th century have been brought to Horyuji temple, and the fact that these Buddhist statues were established in close relation with the Three Kingdoms period in Korea, especially Baekje, has already been revealed through the work of many domestic scholars. Therefore, to examine the Buddhist art of Horyuji temple, which could be the representative of Asuka period Buddhist art, will reversely be a necessary task for studying Buddhist art in the Three Kingdoms period in Korea. Taking this importance into consideration, this study attempts to examine the Halo pattern of the Baekje Buddhist statue in the Three Kingdoms period as a whole, and examine the Halo pattern of the seated gilt bronze Sakyamuni triad enclosed in Geumdang of Horyuji temple in Japan. From the results of this study, the Halo pattern of the seated gilt bronze Sakyamuni triad of Geumdang in Horyuji temple proved that the sculptural form of Buddhist statues in Baekje had an absolute effect as recorded in the Japanese NihonShoki, and through the inscriptions on the back of Halo, it was also confirmed that this statue was constructed by Doribulsa (止利佛師) from Baekje. Through vessel shape halos of the Northern Wei Dynasty and Kokuryeo, Baekje and Shilla of our country and single Mandola Buddhist Triad forms, this study investigated the influence relationship with Horyuji temple Sakyamuni triad, and in the case of lotus flower pattern, Arabesque pattern, and flame pattern, etc., which were in Halo, we could see that there was familiarity with patterns in the Baekje period. Although the comparison target of this study is limited to the gilt bronze Sakyamuni triad enshrined in Geumdang of Horyuji temple, through some of these facts, it is found that there is a close similarity between the style of Buddhist art at the time when Horyuji temple was founded and the style of Buddhist art of Baekje from the second half of the 6th century to the early 7th century, and it is also confirmed the Buddhist statue propagation of the Three Kingdoms period, in which this study may leave its significance.

북위 운강석굴(雲岡石窟) 불상 양식과 화염광배문양 고찰

고승희(Koh, Seung-Hee) 동서미술문화학회 2017 미술문화연구 Vol.10 No.10

본 연구는 중국 북위때 조성한 운강석굴의 불상 양식과 광배문양의 연구를 통해 우리나라 삼국시대, 특히 고구려 불상의 광배문양 형성에 어떠한 영향력을 미쳤는지에 대해 파악해 보고자하였다. 중국의 불교사상 변화에 따라 조성되는 석굴사원 가운데 북위(北魏, 386~534) 화평원년(和平元年, 460년)에 사문통 담요(沙門統曇曜)가 조영한 운강석굴(雲岡石窟)은 중국내에서 처음으로 개착한 본격적 석굴사원이고 국가적으로 총력을 기울려 조성되었다는 것과 따라서 규모와 예술성이 돋보인다는 부분에서 매우 중요한 위치를 차지한다. 더욱이 중국 북위의 불상은 삼국시대의 불상 양식과도 연결시킬 수 있어 우리나라 고대 불상연구에도 빼놓을 수 없는 석굴사원 가운데 하나다. 따라 운강석굴의 도상 특징 가운데 구체적인 유형으로 살펴볼 수 있는 광배 무늬를 파악해봄으로써 아직까지 미비하게 연구되어온 우리나라 삼국시대, 특히 고구려 불상의 광배 문양과의 영향관계를 살펴보는 것은 매우 중요하다고 할 수 있다. 이런 중요성을 감안해서 연구한 결과 첫째, 중국의 불교 사상의 흐름에 맞추어 북위시기에는 불교와 황실 간에 국가적인 거대한 프로젝트 사업인 석굴사원을 조성하여 국가에 불교사상을 확고히 정착화 시키기에 이르렀으며, 이는 태무제의 폐불 정책에도 불구하고 오히려 중국불교의 정확한 색채를 다시 확인시켜주는 좋은 계기가 되었다는 사실을 알 수 있었다. 둘째, 운강석굴의 불상 조성은 당시 시대의 불교사상과 정책의 흐름 속에서 불상의 형식과 양식이 어떻게 변화되어 왔는지 보여주었다. 셋째, 북위시기 운강석굴 불상 양식은 우리나라 삼국시대와 일본의 불상 양식에 영향을 주어 한 · 중 · 일 삼국간의 불교미술의 문화적 흐름을 파악할 수 있었다. 특히 광배에 표현된 화염무늬는 인도의 초기불상에서는 찾아 볼 수 없는 문양으로 중국에서 새롭게 탄생한 광배 표현을 삼국시대 고구려 불상 조성 형식으로 받아들이고 다시 변화시켜 고구려만의 양식을 다시 창출하였다. 이러한 영향관계는 불상의 여러 가지 도상 특징 가운데 가장 구체적으로 나타낼 수 있는 양식으로 광배문양을 대표할 수 있음을 알 수 있다. 이와 같이 운강석굴 불교미술은 서로의 유기적인 관계 속에서 계속 발전 · 쇠퇴하면서 끈임없이 새로운 예술문화를 이끌어내는 관계를 갖고 나아가 삼국시대의 불교문화에도 지대한 영향력이 있었음을 살펴볼 수 있다. Through investigating the Buddha image style and halo pattern of Yungang Caves sculpted in Beiwei, China, this study attempted to explore their influence on the halo pattern formation of Buddha images especially in Koguryeo during the Three Kingdoms period. Among the rock cave temples created according to changes of Chinese Buddhist thought, the Yungang Caves (雲岡石窟), built by Samuntong Damyo (沙門統曇曜) at 460 in Hwapyeong (和平元年) in Beiwei (北魏, 386‐534) are the first full‐scale rock cave temples developed in China, and it is very important in that they are made with national strength and therefore their size and artistry stand out. Moreover, the Buddha images in Beiwei, China can be linked to the Buddha image style of the Three Kingdoms, which is one of the rock cave temples indispensable to the study of ancient Buddha images in Korea. Therefore, by identifying the halo pattern that can be seen as a concrete type among the iconographic style characteristics of the Yungang Caves, it is very important to examine the relationship between the halo patterns of Buddha images of especially Koguryeo in the three kingdoms period, which have been studied insufficiently. From the results of the study in consideration of this importance, first, in accordance with the flow of Buddhism in China, in the Beiwei period, the country came to the state to firmly fix Buddhist thought by establishing rock cave temples, a huge national project between Buddhism and the imperial family, and it was a good opportunity to reaffirm the accurate color of Chinese Buddhism in spite of the Buddhism abolishment policy. Second, the composition of the Buddha images of Yungang Caves showed how the form and style of the Buddha images changed in the flow of Buddhist thought and policy of the time. Third, the style of the Buddha images of Yungang Caves during the Beiwei period influenced the Buddha image style of the Three Kingdoms period in Korea and Japan, which demonstrates the cultural flow of Buddhist art between three countries including Korea, China and Japan at the time. In particular, the flame pattern expressed in the halo is a pattern that cannot be found in the early Buddha images in India, and the halo expression newly born in China was accepted as a form of Buddha images of Goguryeo in the Three Kingdoms period. Goguryeo changed the style again, and the style of Goguryeo was re‐created. It can be seen that this influence relationship can be represented by the style of the pattern represented most specifically among the various features of Buddha images. Thus, as the Buddhist art of Yungang Caves continued to develop and decline in the organic relationship of each other, and had a relationship that lead to a new art culture. Furthermore, it can be seen that it influenced the Buddhist culture of the Three Kingdoms period.

스월-안정화 연소기에서 화염구조와 연소불안정에 대한 연구

황동현,박수진,안규복 한국연소학회 2020 한국연소학회지 Vol.25 No.2

Flame structure and combustion instability characteristics in a swirl-stabilized combustor were investigated by changing fuel, inlet mean velocity, equivalence ratio, and swirler geometry. Two different premixed gases consisting of air and hydrocarbon fuels (C2H4, CH4) were supplied to a combustion chamber through an inlet section and an axial swirler. Dynamic pressure transducer and ICCD camera with a bandpass filter were used to measure pressure fluctuations and flame structures, respectively. The experimental results showed that the pressure fluctuations significantly increased, accompanied by the flame structure transition under certain conditions. Hollow cone flames were mainly formed under stable combustion, but heat release was distributed near the central axis of the combustion chamber under the combustion instability.