• 한국자동차공학회논문집
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• 제8권6호
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• pp.79-86
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• 2000

The effects of recirculated exhaust gas on the wears of piston and piston rings were investigated by the experiment with a two-cylinder, four cycle, indirect injection diesel engine operating at an engine load of 75% and an engine speed of 1600 rpm. For the purpose of comparison between the wear rates of two cylinders with and without EGR, the recirculated exhaust gas was sucked into one of two cylinders after the soot contenets in exhaust emissions were removed by an intentionally designed cylinder-type scrubber equipped with 6 water injectors(A water injector has 144 nozzles of 1.0 mm diameter), while only the fresh air was inhaled into the other cylinder. These experiments were carried out on the fuel injection timing fixed at 15.3$^{\circ}$ BTDC. It was found that the wear rate of piston skirt with EGR increased a little bit, but the piston head diameter increased, rather than decreased, owing to soot adhesion and erosion wear, and especially larger with EGR, and that the wear rates of the top and second piston ring(compression ring)thickness with EGR were more than twice the wear rate of top ring in case of no EGR, but the wear rate of oil rings thickness without EGR increased greater than that with EGR.

• Journal of Mechanical Science and Technology
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• 제15권11호
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• pp.1524-1532
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• 2001

The effects of recirculated exhaust gas on the wear of cylinder liner and piston were experimentally investigated by a two-cylinder, four cycle, indirect injection diesel engine operating at 75% lo ad and 1600 rpm. For the purpose of comparison between the wear rates of the two cylinders with and without EGR, the recirculated exhaust gas was sucked into one of two cylinders after the soot in exhaust emissions was removed by an intentionally designed cylinder-type scrubber equipped with 6 water injectors(A water injector has 144 nozzles of 1.0 mm diameter), while only the fresh air was inhaled into the other cylinder. These experiments were carried out with the fuel injection timing fixed at 15.3$^{\circ}$ BTDC. It was found that the mean wear rate of cylinder liner with EGR was greater in the measurement positions of the second half than those of the first half, that the mean wear rate without EGR was almost uniform regardless of measurement positions, and that the wear rate of piston skirt with EGR increased a little bit, but the piston head diameter increased, rather than decreased, owing to soot adhesion and erosion wear, and especially larger with EGR.

• 한국융합학회논문지
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• 제11권7호
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• pp.163-167
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• 2020

본 연구에서는 피스톤 헤드의 형상별 열응력해석을 진행하여 내구성이 있는 피스톤의 형상을 고찰하기 위한 연구를 진행하였다. 그 결과로서는 온도가 가해지는 부분에서부터 거리가 멀수록 낮은 온도를 볼 수 있다. 피스톤 헤드의 형상에 따라 열을 받는 면적이 다르기 때문에 피스톤 기둥 부분과 스커트부에 영향을 끼치게 된 점을 볼 수 있었다. 본 연구에서는 세 모델이 동일하게 피스톤 헤드의 중심부에서 가장 적은 응력이 나오는 것을 알 수 있었다. Model A는 다른 두 모델에 비해 항복이 발생하는 응력이 가장 작은 것을 알 수 있었다. Model B는 접시형 피스톤헤드로서 피스톤 헤드부가 오목한 형상으로 되어 있어 피스톤 헤드 중심부에서는 주변 부분에 영향을 가장 덜 끼치는 모델임을 알 수 있었다. Model C는 항복이 발생하게 되는 응력이 가장 크게 보였다. 또한 본 연구결과는 내구성이 있는 피스톤의 형상 설계에 유용하게 적용할 수 있다고 사료된다. 피스톤 헤드의 형상에 따른 열응력 해석을 적용함으로서, 본 연구가 미적인 융합에 부합된다고 사료된다.