• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 춘계학술대회 논문집
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• pp.131-132
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• 2007

• Journal of Advanced Marine Engineering and Technology
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• 제15권5호
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• pp.47-54
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• 1991

The lip seals widely used nowadays in stern tube sealing system of ships have radial sealing contact with shafts or liners, on the other hand the face seals of stern tube sealing system have axial sealing contact with seat. Because of axial sealing contact, the face seals have a large number of merits such as durability of life, simplicity of structure, easy fitting and replacement, etc. In this paper, for the purpose of development of face seals, the fundamental properties of axial sealing contact were analyzed and a trial face seal was designed and manufactured using N.B.R. rubber and Thordon which is widely used for bearing materials. The seal proper of trial face seal was made from N.B.R. rubber and the face insert was made from Thordon, thermosetting resins which are three dimensional, cross linked condensation polylmers. The performance test of trial face seal was carried out on the test bench which was specially designed and manufactured. The results were satisfactory enough to be used in practical stern tube sealing system.

• 오토저널
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• 제13권6호
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• pp.82-89
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• 1991

In order to investigate the characteristics of flow around the intake around the intake valve exit, discharge coefficient and the velocity near the valve exit in steady state were measured using X-type hot-wire. Valve and valve seat insert used in experiment were constructed as the same shape of production engine and the flow characteristics at various flow rates and valve lifts were investigated. From the results of discharge coefficient measurements, it is observed that there exists a similarity between the flow characteristics around the production engine valve and the typical poppet valve. Measurement of the velocity at the valve exit shows that the normalized radial velocity between the primary direction of flow and the valve angle is large, but the difference becomes smaller as the flow rate increases.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.33-41
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• 2008

Architectural acoustics design of Namsadang exclusive use theaters should be designed to utilize variously to performance space that can fill flavor and taste of Namsadang performance of the Namsadang six yards. Also, analyze special quality that is sound enemy who follow in sound-absorbing materials fare arrangement of innards that is design material of architectural acoustics laying stress on tradition, use purpose and disappointment size that Namsadang exclusive use theaters seeks on the basis of specific space theme that is experience, disappointment form, seat and passageway Wall and ceiling etc. research and sound and meaning of a character wave motion powerful engineering phenomenon and reduction reverberation loss that is happened from indoor manufacturing thing reduction SCALE model of oval structure research and background of AL composition absorbing material of perforate 25% to heighten acoustic absorptivity of practical use internal organs sound absorption material emir quality sound-absorbing materials insert and layer of air most suitable reverberation time of Namsadang exclusive use theaters that 2.2m volume is $42,218\;m^3$ to become 1.2Sec architectural acoustics design do.

• 한국산학기술학회논문지
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• 제21권2호
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• pp.373-380
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• 2020

고압을 받는 플랜트용 제품 설계 시에 대부분 강건 구조를 지양하다 보면 안전율이 높아지고 중량이 과다 해지는 문제가 있다. 본 논문은 플랜트용 이축 볼밸브 볼의 경량화를 위하여 밸브의 3차원 모델링과 ANSYS를 적용한 유한요소해석으로 응력해석을 수행한 후에, 허용 응력 범위와 설계 변경 제한 조건 내에서 최적화 과정으로 볼의 중량 감소를 달성하였다. 약 22%의 볼 중량이 감소되었고 응력은 증가하였으나 안전계수는 1.25가 되었다. 볼의 일부분에 과도한 응력이 있으나 대부분 재료의 항복응력 허용치 내에 있어 안전한 상태이다. 유동의 흐름을 제어하는 실링 (seal) 역할을 하는 시트 인서트와 시트 링 등 밸브의 3차원 모델에 대한 정적 구조해석으로 응력 값을 확인하여 안전함을 확인하였고, 또한 대칭 구조인 부분에 대해 2차원 단순 모델의 구조해석으로 같은 결과가 도출됨을 확인하였다. 본 연구의 범위는 볼의 중량 감소라 볼의 감소된 치수가 도출되었으며, 주변 부재의 재설계는 (신제품 개발에 해당되어) 본 연구에 고려되지 않는다.