• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.494-497
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• 2009

풍력터빈 블레이드 풍동시험의 경우 사용가능한 시험설비의 크기제한으로 인해 축소모델 사용이 불가피하며, 이로 인해 풍동시험에서는 실물 블레이드에 비해 10% 미만의 낮은 Re수에서 시험이 수행된다. 축소모델 블레이드 풍동시험 결과를 활용하여 실물 블레이드의 성능(토크)를 추정하기 위한 축소효과 보정기법을 2008년 제시하였으며, NREL Phase VI 모델 시험결과에 적용하였다. 당시 제시된 보정기법은 단일익형을 전체 블레이드에 사용한 사례이며 축소효과 보정을 위해 Re수에 따른 익형의 양력계수 변화만을 적용하였다. 본 논문에서는 당시 제안된 축소효과 보정기법을 익형의 양력계수 및 항력계수를 포함한 형태로 수정하였으며, 블레이드에 다수의 익형이 사용되었을 경우에 대해 확장하였다. NREL Phase VI 12% 시험모델의 경우 익형의 양력계수 기울기에 의한 보정량은 약 15% 정도이며, 항력계수 변화에 의한 보정량은 약 5% 정도로 나타났다. 블레이드에 다수의 익형이 사용되었을 경우 설계 또는 전산해석을 통해 구한 반경별 토크 함수를 적용하여 블레이드 축소효과를 보정할 수 있다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.6
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• pp.475-484
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• 2012

Numerical investigation is performed to understand the effects of thickness uncertainty of a supporting airfoil due to manufacturing processes on the aerodynamic characteristics of an airfoil used for measuring data in a wind tunnel testing. This is done by comparing the coefficients of lift, drag and moment of the airfoils. In this work, the airfoil model consists of three parts, one located in the center for measuring and two outer parts used for supporting. The study is carried out with a NACA64-418 airfoil and the turbulence model of Transition SST. It is found that the effect of thickness uncertainty of the airfoils used for supporting is not significant to the performance of the test airfoil at various angles of attack and Reynolds numbers.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.3
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• pp.212-216
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• 2017

Aerodynamic analysis for the airfoil, KARI-11-180 having 18% thickness ratio, was performed with CFD techniques. The boundary layer grid was generated by projecting the wall grid normally and fine grid was placed behind the trailing edge to capture the wake accurately. The distance to the far boundary is 100 chords and the flow condition is same as the wind tunnel test condition. Transition SST and DES turbulence models were utilized for accurate prediction of the transiton point. The predicted lift is higher but the drag is predicted lower than the wind tunnel test. 3-dimensional results with airfoil models of which aspect ratio were 2 and 5 were compared with 2-dimensional results.

• Aerospace Engineering and Technology
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• v.4 no.2
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• pp.36-41
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• 2005

The aerodynamic characteristics of the oscillating airfoil(NACA0012) were measured by experimental methods by using the airfoil oscillating test rig installed at KARI 1m wind tunnel. The chord of the airfoil is 0.2m and the span is 0.75m. The lift and pitching moments were calculated by integrating the surface pressure measured by strain-gage type pressure sensors. The test condition is like this : the reduced oscillating frequency(k) < 0.1, Re ~ 820,000, Mach < 0.25. The test results were compared with the reference data published by other facilities.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.6
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• pp.481-486
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• 2011

The evaluation of supercooled water droplet impingement characteristics of full-scale aircraft components in wind tunnels under icing conditions has been severely limited by the relative size of the component and the test facility. The concept of truncated airfoil sections has been suggested in order to extend the operational range of icing tunnels. With proper deflection of the small trailing-edge flap on the truncated airfoil the local pressure distribution may remain very close to that of the full-scale airfoil. In this study the shape of a truncated flapped airfoil is investigated for various deflection angles. To validate the truncated flapped airfoils, air flow and collection efficiency over the truncated airfoil are compared with the results of the full-scale airfoil obtained from the state-of-the-art icing simulation code.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.3
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• pp.194-201
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• 2017

The KARI-11-180 airfoil was selected as a model for EFD-CFD comparison workshop case 1. Wind tunnel test for this model was conducted in KARI low speed wind tunnel with $0.6m{\times}3.0m$ model for the Reynolds number up to 3.0E6. The model configuration and wind tunnel test results including Cl, Cd and Cp were released at the KSAS 2015 spring conference. The computational analysis results with KFLOW, FLUENT and STAR-CCM+ were present in the KSAS 2015 fall conference. These computational works were summarized in this paper and the comparison results with each others including the wind tunnel data were also summarized.

• 한국전산유체공학회:학술대회논문집
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• 2007.10a
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• pp.167-170
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• 2007

In the present paper, wall correction method is reviewed and applied to the numerical experimental results obtained at the wind tunnel condition. The corrected lift coefficient agrees well with the reference data generated from the grid having very far boundary. However the corrected drag coefficient presents some deviation from the reference data.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.5
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• pp.18-23
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• 2004

Wind tunnel test for Forward-Swept wing airplane model, a part of the Korea-Russia technical cooperation program has been conducted at both TsAGI T-102 and KARI LSWT. The results of TsAGI T-102, obtained by using a unique wire-suspension model support system, and KARI LSWT, used tripod and tandem strut arrangement configuration, are compared with various model conditions including control surface deflection such as flap, aileron, elevator and rudder. Good agreement in the value of drag-polar is observed between TsAGI T-102 and KARI LSWT data. The lateral and directional stability coefficients with rudder and aileron deflection represent a good agreement in both facility.

• Aerospace Engineering and Technology
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• v.7 no.2
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• pp.27-30
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• 2008

Wall correction method for wind tunnel test is reviewed and applied to the numerical experimental results obtained at the wind tunnel condition. The corrected lift coefficient agrees well with the reference data generated from the grid having very far boundary However the corrected drag coefficient presents some deviation from the reference data.

• The KSFM Journal of Fluid Machinery
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• v.12 no.5
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• pp.61-65
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• 2009

현재 선진업체들은 성능과 구조적으로 경쟁력 있는 산업용 가스터빈 압축기를 설계하기 위하여 항공기용 압축기 설계기술을 전용하고 있다. 따라서 두산중공업은 DGT-5 압축기 익형설계를 위해 항공용 익형설계에 적용되는 S-Profile 설계기술을 활용하여 설계하였으며 현재 DGT-5 압축기에 대한 1차 성능시험이 완료되어 만족할 만한 결과를 얻었다. 그리고 DGT-5 압축기는 추후 두산중공업 파생형 가스터빈 압축기의 기본압축기로 활용할 계획이다.