• Proceedings of the KIPE Conference
• /
• 2010.11a
• /
• pp.250-251
• /
• 2010

본 연구는 수평축(horizontal axis) 풍력 터빈에 의해서 수직축 발전기를 운전하는 구조 및 그 운전 방식에 관한 것으로서 바람에 의해 수평축 터빈 로터로 입력된 회전력을 기계적으로 두 개의 수직축 회전 성분으로 변환하여 이들로부터 전기 에너지를 얻어내고 필요에 따라 터빈 날개가 바람이 부는 방향을 향하도록 yaw-axis 제어를 하는 기술에 관한 것이다.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.41 no.11
• /
• pp.849-854
• /
• 2013

Experimental study was conducted to investigate aerodynamic interference effect of wing tip vortex in formation flight of high speed aircraft. In formation flight, wing tip vortex produced by leading aircraft can affect on the aerodynamic characteristics of trailing aircraft. The interference effect of flow is varied with distances between wing tips of leading and trailing aircraft. It is confirmed, in this study, that the interference of wing tip vortex generated from the leading aircraft makes the aerodynamic forces and moments of the trailing aircraft with the vertical or horizontal positions of the trailing aircraft. Especially, the lift coefficients of trailing aircraft were highly increased at y/b=-0.125, z/b=0.0 or deeply decreased at y/b=-0.5, z/b=0.38. The interfering pattern of wing tip vortices from two aircraft is precisely observed.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.31 no.9
• /
• pp.1-8
• /
• 2003

Velocity data were acquired at a series of stations in the chordwise direction above a delta wing with leading edge extension, using a triple axis hot film anemometry. Surveys normal to planform yield velocity field data at incidence angle of 24$^{\circ}$and 32$^{\circ}$at a centerline chord Reynolds number of $1.76{\times}10^6$. Experimental results of velocity measurements of mean velocity of three components gave a confidence to quantitative investigate the vortical flow field over a LEX-delta wing with this probe. The present experiments indicated the existence of both wing and LEX vortex where the local mean axial velocity is maximum. It also shown the development of secondary vortex of opposite sign of rotating above the wing surface near the leading edge. The insertion of probe across the flow field was found to have little influence on the position of the vortex core.

• Proceedings of the KIPE Conference
• /
• 2004.07a
• /
• pp.137-140
• /
• 2004

풍력발전은 태양광발전과 더불어 대체에너지의 큰 축을 이루고 있는 대체에너지 시스템이다. 풍력발전은 축의 방향에 따라 수직축과 수평축 풍력발전으로 나뉘는데, 국내외 보급되고 있는 대부분의 시스템은 수평축 발전시스템이다. 이 시스템들은 3개의 날개를 가지는 블레이드를 사용하고 있다. 대용량으로 갈수록 블레이드의 크기는 커지고 시스템에서 발생되는 소음문제, 시스템 운용에서 오는 안정성 등 많은 문제들을 가지고 있다. 본 논문에서는 이러한 문제점들을 보완하고자 수직형 풍력발전시스템을 제안하였으며, 이를 위해 발전시스템의 주요 구성품인 수직형 특수 블레이드를 제안하였다.

• Proceedings of the KIEE Conference
• /
• summer
• /
• pp.1516-1518
• /
• 2004

풍력발전은 태양광발전과 더불어 대체에너지의 큰 축을 이루고 있는 대체에너지 시스템이다. 풍력발전은 축의 방향에 따라 수직축과 수평축 풍력발전으로 나뉘는데, 국내외 보급되고 있는 대부분의 시스템은 수평축 발전시스템이다. 이 시스템들은 3개의 날개를 가지는 블레이드를 사용하고 있다. 대용량으로 갈수록 블레이드의 크기는 커지고 시스템에서 발생되는 소음문제, 시스템 운용에서 오는 안정성 등 많은 문제들을 가지고 있다. 본 논문에서는 이러한 문제점들을 보완하고자 수직형 풍력발전시스템을 제안하였으며, 이를 위해 발전시스템의 주요 구성품인 수직형 특수 블레이드를 제안하였다.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.8
• /
• pp.579-585
• /
• 2019

Increasing the detection probability of underwater targets necessitates securing the towing stability of the active towed SONAR. In this paper, to confirm the effects of tail wing fin on towing attitude and towing stability, two scale model experiments and one sea trials were conducted and the results were analyzed. The scale model tests measured the towing behavior of each of the tail fin shapes according to towing speed in a towing tank. The shape of the tail fin used in the scale model test was tested with an I-type tail fine and four Y-type tail fins, totaling five tail fins of the two kinds. The first scale model test confirmed that the Y-type tail fin was superior to the I-type tail fin in towing attitude and towing stability. The second scale model test confirmed the characteristics of the vertical tail fin height increase and the lower horizontal tail fin inclination angle application shape based on the Y-type tail fin. The shape of the application of the lower horizontal tail fin inclination angle showed the best performance. In order to verify the results of the scale model test, a full size model was constructed, sea trials were performed, and the towing attitude was measured. The results were similar to those of the scale model test.

• Magazine of RCR
• /
• v.11 no.3
• /
• pp.29-31
• /
• 2016

• Proceedings of the Korean Society For Composite Materials Conference
• /
• 1999.11a
• /
• pp.264-267
• /
• 1999

복합적층판은 일반적으로 균일한 두께를 갖는 평평한 구조물을 형성하게 된다. 그러나 실제 적용시 적층판의 테이퍼링(tapering)이 요구되는 경우가 존재한다. 테이퍼진 복합재 구조물의 적용분야는 항공기의 날개, 수직/수평 안정판 및 헬리콥터의 로터 블레이드 등이다. (중략)

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.30 no.4
• /
• pp.38-43
• /
• 2002

A study on the test, design and fabrication of wind tunnel model for measurement of air load distribution on wing surfaces is presented. 447 pressure taps are installed normal to the wing surfaces, and measured by PSI-8400 system using total 8 ESPs modules installed in the model. The test was performed at 50 m/sec constant speed in the low speed wind tunnel of Agency for Defense Development. Tests were carried out to determine effects of angle of attack, angle of sideslip and flap and stores for the load distribution of wing. The test results in this paper can be applied to the design optimization of structure and validation of computational fluid dynamics.

• Journal of Energy Engineering
• /
• v.29 no.1
• /
• pp.34-43
• /
• 2020

A study has been done for self-starting torque of vertical axis wind turbine blade. It is especially concentrated to evaluate the torque coefficient before starting rotation. Two different aerofoils(AMI903 and AMI904) are proposed to benchmark the possible best blade(supercritical airfoil) for self-starting performance. Torque coefficients in the tangential direction of rotation are given with respect to the angle of attack in terms of drag coefficient and lift coefficient. Torque coefficient shows that the effect of Reynolds number is minimal. The thicker blade(AMI904) between two different proposed airfoils has bigger torque coefficient, which is attributed to lower lift coefficient and higher drag coefficient.