• 제목/요약/키워드: 선박디젤엔진

검색결과 206건 처리시간 0.028초

비파괴법에 의한 선박용 디젤엔진 배기밸브의 열화도 평가에 관한 기초적 연구 (Fundamental Study on Degradation Evaluation of Marine Diesel Engine Exhaust Valve by Nondestructive Test)

  • 심규현;김현수;남기우
    • 동력기계공학회지
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    • 제3권4호
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    • pp.51-56
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    • 1999
  • The ultrasonic method, which is well known as nondestructive test method, is widely used to evaluate the material damage due to degradation. However, this method is just used for measuring the crack size and the thickness loss of the tube. The purpose of this study is to investigate the applicability of the ultrasonic technique for the evaluation of marine diesel engine exhaust valve and to suggest the correlations between the ultrasonic characteristics and valve degradation. From the evaluation of the results obtained, the technique of using the ultrasonic property was founds to be a efficient method to evaluate the degree of marine diesel engine exhaust valve by nondestructive test.

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선박용 중속디젤엔진 연료분사노즐 해석 연구 (Study on Simulation of Fuel Injection Nozzle for Marine Medium Speed Diesel Engine)

  • 양영준
    • 한국기계가공학회지
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    • 제12권3호
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    • pp.41-47
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    • 2013
  • This study was carried out to improve the design of fuel injection nozzle for marine medium speed diesel engine. For this purpose, fuel injection nozzle was modeled and simulated using CATIA V5R19 and FLUENT & MSC Nastran. Analyses of flow and heat transfer, respectively, were performed to find the optimal design of fuel injection nozzle. As the results, big pressure drop, which may lead to cavitation damage, was occurred at inlet of fuel injection hole with diameter 0.3mm. Furthermore, it was confirmed that the increase of mean temperature of fuel injection nozzle was almost a half in comparison with that of fuel injection nozzle tip.

선박용 4행정 디젤엔진의 과도 비틀림 진동에 관할 연구 (A study on the Transient Torsional Vibrations of Four Stroke Marine Diesel Engines)

  • 이돈출;유정대;전효중
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2002년도 추계학술대회논문집
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    • pp.44-50
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    • 2002
  • Theoretical analysis on the transient torsional vibration was started from early 1960's for high power synchronous motor application. As for marine engineering, simulation and measuring techniques of transient torsional vibration have been steadily studied by manufacturer of flexible coupling and designer of four stroke marine diesel engine. In this paper, the simulation method of transient torsional vibration for four stroke marine diesel engine application using Newmark method is introduced.

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선박용 디젤엔진의 냉각수 유동에 대한 수치해석적 및 이론적 연구 (Numerical and Theoretical Study on the Fluid Flow in the Cooling System of a Marine Diesel Engine)

  • 서용권;허성규;정성식
    • Journal of Advanced Marine Engineering and Technology
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    • 제32권1호
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    • pp.119-130
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    • 2008
  • Diesel engine is one of the most expensive and important components in a ship. Many researchers are interested in increasing the performance of diesel engines. Design of an optimum cooling system should also contribute to the enhancement of the performance as well as the efficiency of engines. In this study, we investigated the flow pattern within the cooling system of a marine diesel engine by using numerical simulation prior to the study of the heat-transfer problem. The engine cooling system is composed of five cooling units each unit containing a water-jacket and a cylinder head. Based on the calculated data, we also conducted theoretical analysis that can predict the flow-rate delivery in each of the five units.

소형 선박 디젤엔진의 질소산화물 저감에 관한 연구 (A Study on NOx Reduction for a Small Marine Diesel Engine)

  • 심한섭
    • 한국기계가공학회지
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    • 제10권5호
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    • pp.79-84
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    • 2011
  • Air pollutants from a small marine diesel engine are increasing and the IMO(International Marine Organization) regulation asked for its reduction. In this study, NOx reduction technologies such as improvement of various cooling systems are applied to the small marine diesel engine. The various cooling systems are a intercooler, a heat exchanger for engine coolant, and an exhaust manifold by water cooling. These systems are tested on an engine dynamometer and a exhaust gas analyzer by a marine diesel engine test regulation. Test results are shows that the small marine engine are satisfied the IMO NOx regulations; Tire II.

선박용 4행정 디젤엔진의 크랭크축 강도해석에 관한 연구 (A Study on the Strength Analysis of Crankshaft for 4 Stroke Marine Diesel Engine)

  • 이돈출;강대선
    • Journal of Advanced Marine Engineering and Technology
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    • 제30권3호
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    • pp.359-368
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    • 2006
  • The trend on marine diesel engine productions and refinements has led to a higher mean effective pressure and thermal efficiency. These resulted in increased maximum combustion pressure within the cylinder and vibratory torque in crankshaft. In view of this. the crankshaft should be able to withstand the dynamic stresses caused by load variations. Different factors including size, material and stress concentration factors should also be considered to ensure the reliability of the shafting system. As such, crankshaft must be designed and compacted within its fatigue strength. In this paper, the strength analysis of crankshaft Is carried out by: simplified method recommended by IACS(International Association Classification Societies) M53 and a detailed method with the crankshaft assumed as a continuous beam and bearing supported in its flexibility. The results of these two methods are then compared.

선박용 4행정 디젤엔진의 크랭크축 강도해석에 관한 연구 (A Study on the Strength Analysis of Crankshaft for 4 Stroke Marine Diesel Engine)

  • 이돈출;박성현;강대선;김태언
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 춘계학술대회논문집
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    • pp.66-72
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    • 2006
  • Marine diesel engine production and refinements sought a continuous increase on mean effective pressure and thermal efficiency. These results in increased maximum combustion pressure within the cylinder and vibratory torque in crankshaft. As such, crankshaft should be designed and compacted within its fatigue strength. In this paper, the 8H25/33P($3,155ps{\times}900rpm$) engine for ship propulsion was selected as a case study, and tile strength analysis of its crankshaft is carried out by. simplified method recommended by IACS M53 and a detailed method with the crankshaft assumed as a continuous beam and bearing supported in its flexibility. The results of these two methods are compared with each other.

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시간-주파수 해석법을 이용한 선박용 디젤엔진 배기밸브의 열화도 평가에 관한 기초적 연구 (II) (Fundamental Study on Degradation Evaluation of Marine Diesel Engine Exhaust Valve by Time-frequency Analysis Method (II))

  • 김현수;심규현;안석환;남기우
    • 한국해양공학회지
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    • 제14권4호
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    • pp.68-72
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    • 2000
  • The ultrasonic method, which is well known as nondestructive test method, is widely used to evaluate the material damage due to degradation. However, this method is just used for measuring the crack size and the thickness loss of the tube. The purpose of this study is to investigate the application of the ultrasonic technique for the evaluation of marine diesel engine exhaust valve and to suggest the correlation between the ultrasonic characteristics and valve degradation. From the evaluation of the results obtained, the technique of using the ultrasonic property was founds to be a efficient method to degree of marine diesel engine exhaust valve by nondestructive test.

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