http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
정광효(Kwang-Hyo Chung),장종희,전호환(Ho-Hwan Chun) 한국해양공학회 1998 韓國海洋工學會誌 Vol.12 No.2
A numerical simulation was done to investigate the performance of thin wings in close vicinity to ground. The simulation is based on Vortex Lattice Method(VLM) and freely deforming wake elements are taken into account for a sudden acceleration case. The parameters covered in the simulation are angle of attack, aspect ratio, ground clearance, sweep angle and taper ratio. In addition, the effect of the wing endplate on the ground effect is included. The wing sections used for present computations are uncambered, cambered and S-types. The present computational results are compared with other published computational results and experimental data.
다점계류식 FPSO의 해양환경별 계류선 각도와 최대 장력에 대한 연구
박성부(Sung-Boo Park),이승재(Seung-Jae Lee),정윤석(Yun-Suk Chung),이민경(Min-Kyeong Lee),정광효(Kwang-Hyo Jung) 한국해양공학회 2016 韓國海洋工學會誌 Vol.30 No.4
This study demonstrates the result of mooring analysis for five spread-moored FPSOs having different length-to-breadth (L/B) ratios from 4.5–6.5. FPSOs are subjected to four metocean conditions, ones from the Gulf of Mexico (Hurricane/Loop current condition), West Africa, Nigeria, and Brazil Campos Basin, which are amongst the most typical offshore oil and gas fields. With change in design parameters of OBA (Outer bundle angle) and IBA (Inner bundle angle) combinations, a change in the line tension is demonstrated and the OBA-IBA combinations having the smallest line tension are presented for each L/B ratio and sea, respectively. This study is expected to influence the preliminary design layout of an FPSO spread-mooring system as a function of the L/B ratio and metocean conditions.
해면효과익의 실험적 연구와 PARWIG선의 설계 및 제작
장종희,전호환,정광효,이 준 釜山大學校生産技術硏究所 1997 生産技術硏究所論文集 Vol.53 No.-
지면효과(Wing In Ground Effect, WIG)의 개념은 날개가 지면 가까이 비행할 때 유기저항(Induced drag)의 감소와 양력의 증가로 양항비가 증가하는 것이다. 이러한 효과를 이용하여 지면 또는 해면 가까이 항주함으로서 해면효과익선이 같은 속도의 비행기보다 경제성이 좋은 것으로 평가되어지고 있다. 또한 PAR(Power Augmented Ram)현상은 1970년대경 발견된 것으로서 날개 앞에 부착된 프로펠러의 후류를 날개 밑으로 불어넣어 해면효과익선이 저속에서도 이수할 수 있도록 하여 WIG선의 성능을 향상시키는 계기가 되었다. 본 논문은 풍동을 이용하여 지면에서 날개후연까지 높이의 변화, 앙각의 변화 및 날개끝단판(End- plate)의 변화에 따른 날개의 양력, 항력 및 종방향모멘트를 계측하여 분석하고 2.5m급 무선 조종 PARWIG선의 설계개념과 제작과정에 대해서 설명한다. In the early of the 20th century, it was noted that a wing operating in close proximity to the ground exhibits a reduction in induced drag, which increases its lift/drag ratio. For several decades this phenomenon, called the wing-in-ground-effect(WIG), was studied because it complicated the takeoff and landing of aircraft. In the 1970s, the Power Augmented Ram(PAR) phenomenon was discovered, which significantly enhanced the performance of the WIG concept. The main purpose of this study is to design a 2.5m size, remote control PARWIG model aiming to develop an one manned leisure PARWIG craft. The lift and drag force are measured in a wind tunnel for wings with different flying heights, angles of attack and endplates. Based on the experimental results, 2.5m size model craft is designed and constructed.