• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.2
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• pp.99-107
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• 2014

In this study, aerodynamic characteristics of Kline-Fogleman airfoils are numerically investigatied which has been widely used in remote control aircraft operating at low Reynolds numbers. The comparison of aerodynamic characteristics was conducted between NACA4415 and Kline-Fogleman airfoil based on NACA4415. ANSYS Fluent was employed with the incompressible assumption and $k-{\omega}$ SST turbulence model. It was found that lift coefficient was significantly enhanced in the range of Reynolds number from $3{\times}10^3$ to $3{\times}10^6$. Especially in the region of Reynolds number below $2.4{\times}10^5$, the lift-to-drag-ratio was improved by 26% using the Kline-Folgeman airfoil compared with NACA4415 airfoil.

• Transactions of the KSME C: Technology and Education
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• v.2 no.1
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• pp.29-37
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• 2014

In this study, analyzed the aerodynamic characteristics of Kline-Fogleman airfoils and wings with those more efficiency at low Reynolds number. It was found that lift to drag ratio is enhanced in the range of Reynolds number below $2.4{\times}10^5$, especially, can be improved up to 26% at Reynolds number is $1{\times}10^4$. It was confirmed that the most advantage case in terms of lift-to-drag ratio is Middle case and lift-to-drag ratio is improved to 20% at 80% of the wing area is Kline-Folgeman airfoil. At this time, endurance time increase to 12%. Also taking the structural stability of the wing and lift-to-drag improvement into account, designed to be from 50% to 80% the size of the Kline-Fogleman Airfoil would be advantageous.

• Proceeding of EDISON Challenge
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• 2013.04a
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• pp.398-402
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• 2013

NACA 계열 익형의 경우 양력 계수와 양항비는 레이놀즈수가 낮아질수록 감소하는 경향을 보이기 때문에 초소형 항공기에 적용이 어렵다. 따라서 저레이놀즈수 영역에서 높은 양항비를 가지는 익형의 개발이 필요하다. 이에 본 연구에서는 원격 조종 비행기에서 사용되고 있는 KF Airfoil이 저레이놀즈수 영역에서 효율이 좋을 것이라 기대되어 연구를 수행하였다. EDISON CFD와 Fluent를 이용하여 $3{\times}10^3{\sim}3{\times}10^6$ 레이놀즈수 범위에서 KF Airfoil의 공력계수 해석을 수행하였다. 그 결과 $8{\times}10^3{\sim}1{\times}10^5$ 레이놀즈수 영역에서 양항비가 향상되었고 $1{\times}10^4$ 영역에서는 최대 37.3% 향상된 양항비를 확인하였다.