• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.7
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• pp.417-427
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• 2016

This paper is the first investigation of the steady flow characteristics of an SI engine with a semi-wedge combustion chamber as a function of the port shape. For this purpose, the planar velocity profiles were measured at the 1.75B position by particle image velocimetry. The flow patterns were examined with both a straight and a helical port. Two swirls were observed up to 4 mm valve lift with the straight port and up to 2 mm with the helical one; however, only one swirl was present after these lifts. The flow characteristics changed suddenly between 4 and 5 mm lift in the straight port; on the other hand, the change with lift was gradual with the helical port - the transition points between flow regimes were different with the port shapes. In addition, the centers of the swirls were relatively far from the cylinder center so that the effect of eccentricity may not be negligible at 1.75B, regardless the shape. The eccentricity values with the straight port were especially high - over 0.5 for all lifts. Finally, real velocities were found to be much lower than those predicted by the assumption of ISM evaluation, with the profiles differing qualitatively as well.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.2
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• pp.97-107
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• 2017

This study is the second investigation on the steady flow characteristics of an SI engine with a semi-edge combustion chamber as a function of the port shape with varying evaluation positions. For this purpose, the planar velocity profiles were measured from 1.75B, 1.75 times of bore position apart from the bottom of head, to 6.00B positions using particle - image velocimetry. The flow patterns were examined with both a straight and a helical port. The velocity profiles, streamlines, and centers of swirl were almost the same at the same valve lift regardless of the measuring position, which is quite different from the case of the pent-roof combustion chamber. All the eccentricity values of the straight port were out of distortion criterion 0.15 through the lifts and the position. However, the values of the helical port exceeded the distortion criterion by up to 4 mm lift, but decreased rapidly above the 3.00B position and the 5 mm lift. There always existed a relative offset effect in the evaluation of the swirl coefficient using the PIV method due to the difference of the ideal impulse swirl meter velocity profile assumption, except for the cylinder-center-base estimation that was below 4 mm of the straight port. Finally, it was concluded that taking the center as an evaluation basis and the assumption about the axial velocity profile did not have any qualitative effect on swirl evaluation, but affected the value owing to the detailed profile.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.4
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• pp.1-17
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• 2018

This study was conducted to interpret the landscape of Songge Byeoleop(Korean villa) garden at Jogyedong, Bukhansan near Seoul which was built in the mid 17C. to restore through the literature reviews and field surveys. The results were as follows; Songge Byeoleop garden was a royal villa, constructed at King Injo24(1646) of Joseon dynasty by prince Inpyeong(麟坪大君), Lee, Yo(李?, 1622~1658), the third son of King Injo who was a brother of King Hyojong. It was a royal villa, Seokyang-lu under Mt. Taracsan of Gyendeokbang, about 7km away in the straight line from main building. It was considered that the building system was a very gorgeous with timber coloring because of owner's special situation who was called the great prince. The place of Songge Byeoleop identity and key landscape of the place were consisted with Gucheon waterfall and the sound of the water with multi-layered waterfall which might be comparable to the waterfall of Yeosan in China. After the destruction of the building, the place was used for the royal tomb quarry, but there was a mark stone for forbidden quarry. The Inner part of Songge Beoleop, centered with Jogedongcheon, Chogye-dong, composted beautifully with the natural sceneries of Gucheon waterfall, Handam and Changbeok, and artificial structures, such as Bihong-bridge, Boheogak, Yeonghyudang and Gyedang. In addition, the existing Chinese characters, 'Songge Beoleop' and 'Gucheoneunpog' carved in the rocks are literary languages and place markings symbolizing with the contrast of the different forests and territories. They gave the names of scenery to the rock and gave meaning to them. Particularly, Gucheon waterfall which served as a visual terminal point, is a cascade type with multi-staged waterfall. and the lower part shows the topographical characteristics of the Horse Bowl-shaped jointed with port-holes. On the other hand, the outer part is divided into the spaces for the main entrance gate, a hanging bridge character, a bridge connecting the inside and the outside, and Yeonghyudang part for the purpose of living. Also in the Boheogak area, dual view frame structures are made to allow the view of the four sides including the width and the perimeter of the villa. In addition, at the view point in Bihong-bridge, the Gucheon water fall divides between the sacred and profane, and crosses the Bihong-bridge and climbs to the subterranean level.