• 제목/요약/키워드: Combustion pattern

검색결과 193건 처리시간 0.019초

쑥뜸의 연소 특성에 관한 연구 (A Study on the Characteristics of Moxa Combustion)

  • 양승열;이호재;김진우;박영배;허웅
    • 대한의용생체공학회:학술대회논문집
    • /
    • 대한의용생체공학회 1993년도 추계학술대회
    • /
    • pp.128-131
    • /
    • 1993
  • In order to get the basic data for the study of the heat stimulation of burning moxa, the pattern of combustion temperature, which is one of the important factors of thermal characteristics, was measured by density of cone moxa along the time procedure. The following results have been obtained 1) The pattern of combustion temperature by moxa burning was classified into input period which means the infiltration of heat into the area and output period which means the radiation of heat from the area. The input period consists of preheating and heating periods, while the output period consists of heat retaining and cooling periods. 2) The pattern of combustion temperature showed the same type or curve, which was not influenced by the moxa weight. However, Its pattern gradient are varied by density. It is considered that the pattern of combution temperature is primarily influenced by the rate of combustion temperature, gradient temperature and duration of combustion.

  • PDF

Bed Combustion in a Furnace Enclosure - a Model for the MSW Incinerator

  • Ryu, Chang-Kook;Shin, Dong-Hoon;Choi, Sang-Min
    • 한국연소학회지
    • /
    • 제7권1호
    • /
    • pp.58-64
    • /
    • 2002
  • The bed combustion in an incinerator interacts with the gas flow region through heat and mass transfer. Combined bed combustion and gas flow simulations are performed to investigate this coupled interaction for various operating conditions and furnace configurations. Radiation onto the bed from the furnace is interrelated with the combustion characteristics in the bed, and is also affected by the flow pattern in the gas flow region. Since the contribution of gaseous emission to the total radiation is significant, an adequate flow pattern in a well-designed furnace shape would lead to an increased heat influx on the bed, especially in the early stage of the waste combustion. Advancing the initiation point of the waste combustion can also reduce the size of the lower gas temperature region above the bed, which can be achieved by controlling operating conditions such as the waste feeding rate, the bed height and the primary air flow distribution.

  • PDF

애주(艾炷)의 형태별(形態別) 연소(燃燒) 특성(特性)에 대한 연구(?究) - 연소온도(燃燒溫度)의 유형(類型)을 중심(中心)으로 - (An Experimental Study on the Characteristics of Moxa Combustion in the Moxa Cone size - On the Pattern of Combustion temperature -)

  • 박영배;강성길;김창환;고형균;오환섭;허웅
    • 대한한의학회지
    • /
    • 제16권1호통권29호
    • /
    • pp.370-378
    • /
    • 1995
  • In order to consider the clinical efficacy of moxa combustion, understand the quality and quantity of heat stimulation and get the basic data for the development of electric moxibustion apparatus, the pattern of combustion temperature was measured by size of moxa(small, medium, large and maximum size). The results were as follows. 1. The pattern of combustion temperature by moxa burning was classified into input period, consisting of preheating and heating periods, and output period, consisting of heat retaining and cooling periods, in all experimental groups. But it was difficult to observe the preheating period in small sized moxa. 2. It was inclined that the more moxa size was large, the more the heating and heat retaining periods were long and the maximum temperature was high. The characteristics of moxa combustion is primarily by the rate of combustion temperature, gradient temperature and duration of combustion, and their correlation among these factors and their clinical effects in practice.

  • PDF

상업용 소각로 연소실 성능예측을 위한 수치해석 연구 (Numerical Analysis for the Performance Prediction of Combustion Chamber of Commercial Incinerator)

  • 이진욱;박병수;윤용승;서정대;허일상
    • 한국연소학회지
    • /
    • 제4권1호
    • /
    • pp.141-153
    • /
    • 1999
  • Numerical analysis for the combustion flow in the combustion chamber of incineration system has been carried out in order to acquire the basic design capability of incineration system. Established mathematical model was applied to the performance prediction of the pre-designed combustion chamber of commercial plant. Especially, combustion characteristics and the variation of flow pattern have been deeply discussed in accordance with secondary air injection. Secondary air injection was effective for the turbulent mixing between air and carbon monoxide/volatile matter resulting in considerably reduced CO content at the exit. Secondary air injection was found to be one of the key design parameters because the size of recirculation zone could be changed with the variation of injection characteristics.

  • PDF

COMBUSTION CHARACTERISTICS OF INHOMOGENEOUS METHANE-AIR MIXTURE IN A CONSTANT VOLUME COMBUSTION CHAMBER

  • Choi, S.H.;Jeon, C.H.;Chang, Y.J.
    • International Journal of Automotive Technology
    • /
    • 제5권3호
    • /
    • pp.181-188
    • /
    • 2004
  • A cylindrical constant-volume combustion chamber was used to investigate the flow characteristics at the spark electrode gap and the combustion characteristics of an inhomogeneous charge methane-air mixture under several parameters such as stratified pattern, initial charge pressure, ignition time and the excess air ratio of the initial charge mixture. Flow characteristics including mean velocity and turbulence intensity were analyzed by a hot-wire anemometer. The combustion pressure development, measured by a piezo-electric pressure transducer, was used to investigate the effect of initial charge pressure, excess air ratio and ignition times on combustion pressure and combustion duration. It was found that the mean velocity and turbulence intensity had the maximum value around 200-300 ms and then decreased gradually to near-zero value at 3000 ms. For the stratified patterns, the combustion rate under the rich injection (RI) condition was the fastest. Under the initial charge conditions, the second mixture was accompanied by an increase in the combustion rate, and that the higher the mass which is added in the second stage injection, the faster the combustion rate.

일반화염에 의해 소손된 정수기의 연소 확산 패턴 및 화재위험성 평가 (Assessment of the Combustion Diffusion Pattern and Fire Risk of a Water Purifier Damaged by a General Fire)

  • 최충석
    • 한국화재소방학회논문지
    • /
    • 제26권3호
    • /
    • pp.35-39
    • /
    • 2012
  • 본 논문에서는 정수기의 외부 및 내부에서 인위적으로 착화시켰을 때의 연소 확산 패턴을 분석하고, 소손된 정수기의 화재원인 규명을 위한 자료를 제공하는데 있다. 정수기의 연소 확산 속도는 외부에서 착화시켰을 때보다 내부에서 착화시켰을 때 화염의 진행은 빠른 것으로 분석되었다. 외부에서 착화되어 정수기가 반소 이상 되는데 소요되는 시간은 360 sec 정도이었고, 내부에서 착화시켰을 때는 180 sec 정도가 소요되었다. 즉, 내부에서 착화되면 발생된 열이 내부에 축적되었다가 일순간에 방사되기 때문에 연소가 빠른 것으로 판단된다. 외부에서 착화시켜 소손된 것은 균일한 탄화 패턴을 보이며, 바닥면에 탄화물은 순차적으로 퇴적되었다. 내부에서 착화시켜 소손된 것은 탄화면의 경계가 비교적 선명하였으며, 발화점을 기준으로 브이패턴을 형성하였다. 따라서 연소 패턴의 차이를 통해서 어느 쪽에서 화재가 진행되었는지를 판단할 수 있는 객관적 근거가 제시되었다. 정수기가 화염의 공격을 받아 반소될 때까지 내장된 퓨즈의 용단 및 전원 보호 장치의 작동 등은 발생하지 않았다. 또한 일반화염을 공격 받아 소손된 퓨즈는 금속 홀더 부분에서 탄화가 발생하는 것이 확인됨에 따라 사고원인 판정의 근거로 활용할 수 있을 것으로 판단된다.

예연소실식 디젤기관의 운전조건변화에 따른 열발생률 형태변동에 관한 고찰 (A study on the heat release rate pattern variation according to the change of operating conditions in pre-combution chamber type diesel engine)

  • 이진우;최재성;전효중
    • Journal of Advanced Marine Engineering and Technology
    • /
    • 제11권3호
    • /
    • pp.31-44
    • /
    • 1987
  • Nowadays, the problems of energy and environmental pollution become serious day by day and the diesel engine, which has been proved to be superior to gasoline engine with respect to fuel consumption and ecological problems of exhaust gas, has been adopted widely for various purposes from the marine diesel engine and the dynamo engine to all kinds of engine on land. Therefore, extensive parametric studies on combustion of diesel engine should be done for its desing and improvement. To predict the behavior of diesel engien according to variable operating conditions by means of cycle simulation, the reasonable pattern of heat release rate has to be asumed. But it is necessary to know the actual variation of heat release rate in order to assume the reasonable pattern of heat release rate according to the actual operating conditions. In this paper, on a high speed small bore diesel engine with pre-combustion chamber, experimental investigations were carried out to determine the relationship between the heat release pattern and parameters such as engine load and speed. And also, the theoretical investigations about the performance variations of the above diesel engine according to the predicted pattern of heat release rate variation were performed. From the above observations, it may be said that the Fanboro indicator, which was used to get the cylinder pressure, can be used to estimate a reasonable pattern of heat release rate and it is confirmed that the pattern of heat release rate for the pre-combustion type engine is different from that of the direct injection type engine.

  • PDF

Model and Field Testing of a Heavy-Duty Gas Turbine Combustor

  • Ahn, Kook-Young;Kim, Han-Seok;Antonovsky, Vjacheslav-Ivanovich
    • Journal of Mechanical Science and Technology
    • /
    • 제15권9호
    • /
    • pp.1319-1327
    • /
    • 2001
  • The results of stand and field testing of a combustion chamber for a heavy-duty 150 MW gas turbine are discussed. The model represented one of 14 identical segments of a tubular multican combustor constructed 1:1 scale. The model experiments were executed at a lower pressure than that in a real gas turbine. Combustion efficiency, pressure loss factor, pattern factor, liner wall temperature, flame radiation, fluctuating pressure and NOx emission were measured at partial and full loads for both model and on-site testing. The comparison of these items in the stand and field test results led to has the development of a method of calculation and the improvement of gas turbine combustors.

  • PDF

엔진 내 냉각수 유동형태가 연소실 벽면온도에 미치는 영향에 관한 연구 (Effect of Coolant Flow Pattern on Metal Temperature of Combustion Chamber)

  • 민병순;최재권
    • 한국자동차공학회논문집
    • /
    • 제1권1호
    • /
    • pp.14-21
    • /
    • 1993
  • The effect of coolant flow pattern on the metal temperature of the combustion chamber was studied in 1.5L and 1.8L gasoline engines. One of the main important points in the design of the water jacket is the increase of the coolant flow velocity. In this paper, the water jackets of the cylinder head and the cylinder block were visualized for the purpose of improving the coolant flow pattern. By the use of this technique, the optimal design of the size and th location of the water transfer fole was possible. And, to lower the metal temperatures of the thermally critical parts, the drilled water passages were employed. To investigate of effect of the improved flow pattern and the drilled water passages, the metal temperatures of the combustion chamber were measured. As a result of the temperature measurement, it was found out that both the change of flow pattern and the drilled water passages have significant effect on the reduction of the peak metal temperature.

  • PDF

뜸의 대중화 및 유용성 방안에 대한 연구 (The study of standardization plan and usefulness of Moxa Combustion)

  • 이건목;이길숭;이승훈;장종덕;서은미;최정선;김양중
    • Journal of Acupuncture Research
    • /
    • 제20권6호
    • /
    • pp.63-79
    • /
    • 2003
  • Objective: It makes a through study on the popularization and usefulness paln of Moxa Combustion, therefore popularizing practical use of that. Methods: It was based on the established treatises and books, in order to studying about the literature of Moxa Combustion Results & Conclusions: It makes a through study on the whole of Moxa Combustion, the results as follows. 1. We explained(illustrated) the origin, history, classification and mechanism(effect) of Moxa Combustion 2. The study of standardization plan of Moxa Combustion for popularization - The thermal stimulation of Moxa Combustion was decided the characteristic pattern of combustion temperature by moxa burning and that makes a measure to grasp the effective action of Moxa Combustion upon human body. Thereupon it is necessary to continue further studies by analysing the characteristic pattern of combustion temperature by moxa burning and there clinical effects in practice. 3. The usefulness of Moxa Combustion - The therapeutic effect of Moxa Combustion are hematopoiesis(increase the blood), analgesic function, increase the immunity, antioxidant activity, diuretic action, control of hormone(endocrine gland), supression of carcinogenesis, increase the self involution(natural healing), decrease of GOT/GPT, Glucose, Cholesterol level.

  • PDF