• Proceedings of the Korean Society of Marine Engineers Conference
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• 2012.06a
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• pp.252-252
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• 2012

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.11a
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• pp.147-147
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• 2012

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.11a
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• pp.148-148
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• 2012

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.11a
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• pp.150-150
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• 2012

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.05a
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• pp.261-261
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• 2012

• Proceedings of the Korean Society For Composite Materials Conference
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• 1999.11a
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• pp.227-233
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• 1999

This study is mainly concerned with phenomenon of cavitation-erosion on the several materials and corrosive liquids which were applied with vibrator (suggested by ASTM G-32, 20KHZ, 24{$mu}m$).The main results obtained are summarized as follows ; (1) The maximum erosion rate by cavitation erosion in both of fresh-water and sea-water appeared to be proportioned to their hardness and tensile strength. (2) Cavitation weight loss and rate of cast iron in sea-water condition were greater (approximately 3 times) than that in distilled-water condition, however in case of stainless and brass the cavitation weight loss and their rates were not so different in both of their conditions. (3) Cavitation weight loss of composite materials were shown as below on this test, DuraTough DL : Weight loss in sea-water condition were greater (approximately 2.3 times) than it's fresh-water condition. (4) As the result of observation with digital camea of specimens, the main tendency of cavitation erosion for metals, was that small damaged holes causing by cavitation e개sion was appeared with radial pattern, and composites materials was that small damaged holes were appeared randomly.

• Proceedings of KOSOMES biannual meeting
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• 2003.11a
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• pp.157-162
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• 2003

The sludge oils were produced necessarily in the ships operation, so that it will be the best way to manage the sludge oils inside ship itself from a viewpoint of the prevention of marine oil pollution from ship. The ultrasonic breaking systems which recycle the sludge oil from ship into usable oil to be brunt is recognized as a most possible recycling device. In this regards, the purpose of this study is to examine erosion damage on the SS400 specimen by cavitation and the effect of impact pressure generated from the demolition of the cavity of ultrasonic vibration in the marine sludge oil environment .. The erosion damage of specimen was investigated mainly on weight loss, weight loss rate and maximum erosion rate with variation of the oil temperature as well as the change of space between transducer horn and specimen. The experimental results showed that as the space between ultrasonic vibrator horn and specimen disk increased, the weight loss and weight loss rate decreased and the values were larger in SFO than in SLO. The experimental results can be useful to the development of sludge oil disposing systems and to consider a countermeasure for the prevention of erosion damages by cavitation.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.32 no.3
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• pp.302-309
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• 1996

Cavitation erosion-corrosion implies damage to materials due to the shock pressure or shock wave that results when bubbles form and collapse at a metal surface within a liquid. If the liquids corrosive to the material, a condition typically encountered in industry, the component materials may suffer serious damage by a combination of mechanical and electrochemical attack. To suppress cavitation erosion as well as cavitation erosion-corrosion to hydraulic equipments, innovations such as the improvement in the geometric design of the equipment or the selection of suitably resistant construction materials are necessary. This study was tested by using the piezoelectric vibrator with 20kHz, 24${\mu}$m for cavitation generation. And also, the vibratory cavitation erosion-corrosion tests on commercial mild steel SS41were carried out. We carefully observed the erosion pattern and surface photography. The geometrical mechanism of pit growth, which is to be likely these processing; shallow typelongrightarrowundercut typelongrightarrowwide shallow type.

• Journal of the Korean Society of Safety
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• v.24 no.2
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• pp.1-6
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• 2009

A flow analysis for the erosion-corrosion damaged automotive water pump which causes vehicle fire is numerically performed using the CFX program, computational fluid dynamics (CFD) code. The blade bending deformation and the blade clearance enlargement are considered in the analysis of performance reduction. For the cavitation analysis, the homogeneous multi phase model is adopted using the Ralyleigh-Plesset model for the rate equation controlling vapor generation and condensation.

• Journal of Korea Ship Safrty Technology Authority
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• v.7
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• pp.27-37
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• 2001

소형 어선의 조업 환경을 개선하고자 하는 선주와 어민 입장에서 연안에서 번번히 발생하는 그물 걸림이나 충돌시 손상이 적은 추진장치를 저렴하게 공급받기를 원한다. 어선의 고속화 및 낚시전용선 개발 추제에 부응하여 어선용 소형 물제트 추진장치의 특성을 파악하고, 시스템의 개념 설계, 시제품 제작과 시운전 시험을 통하여 실용화 가능성을 검토하였다. 어선의 저항 감소, 캐비테이션 억제 등과 관련된 한계 기술을 개발하는 후속 연구가 진행되고 있다.