• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.467-470
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• 2004

In early 2004, KARI developed 5ft S-Band TT&C antenna for especially KOMPSAT-2 operation in LEOP phase. This paper shows system features of 5ft S-Band antenna and its test result with KOMPSAT-l. Tracking test, command uplink test and telemetry downlink test were performed. Through tests, 5ft antenna was verified to be operational in uplink and downlink with KOMPSAT series. Due to its inherent wide 3dB beam-width of about 7deg at S-Band, this antenna system can be used very effectively even though orbital information is less accurate like LEOP and spacecraft safe mode.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2006년도 추계 학술대회논문집
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• pp.155-158
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• 2006

In the present paper, the scale effects of two-dimensional airfoil and three-dimensional wind turbine were investigated by using FLUENT software. For two dimensional analysis, flow around S809 airfoil with various Reynolds No. and Mach No. conditions were simulated. For three dimensional analysis, scaled NREL Phase VI wind turbine models from 6% to 1,600% were simulated under the same tip speed ratio condition. Finally, aerodynamic comparisons between two-dimensional flow and three dimensional wind turbine flow are made for the feasibility study of scale effect corrections. Currently, KARI(Korea Aerospace Research Institute) is preparing for the wind tunnel test of 12% NREL Phase VI wind turbine and the performance analysis of the scaled NREL wind turbine model will be validated by the wind tunnel test.

• 한국전산유체공학회지
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• 제15권4호
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• pp.53-59
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• 2010

Preliminary design of a ground plate, a device installed close to the aircraft model for wind tunnel test to simulate the ground effect, was performed by a numerical simulation. A two-dimensional numerical study was performed initially to decide the optimal leading edge and flap configurations. Then, three-dimensional studies were conducted to decide the optimal flap deflection angle for pressure distribution reduction since the plate and the plate supporting system generate static pressure difference between the upper and lower flow regions. Three-dimensional simulation additionally studied the effect of the clearance between the plate and the wind tunnel side wall. For the efficiency of computation, half model was simulated and a symmetric boundary condition was applied on the center plane. Based on the preliminary design, a ground plate was designed, manufactured and tested at the Korea Aerospace Research Institute(KARI) wind tunnel. The measured pressure differences versus flap deflection angle agreed well with the predicted results.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계 학술대회논문집(수송기계편)
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• pp.41-44
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• 2005

This paper described improvement and operation of a 'Tail-Fan' anti-torque performance test system KARI (Korea Aerospace Research Institute) developed a 'Tail-Fan' anti-torque system of a helicopter and a performance test-rig to test the performance of the Tail-Fan. The test-rig was improved for full rotating test in 4300rpm(100%). Machinery and hydraulic parts ware changed to reduce vibration and to increase safety. To find the operation rotating speed for the performance test, vibration test were carried out rising accelerometers on tail gear box. The performance test conditions of the Tail-Fan to avoid a resonance were found from vibration test results. The Tail-Fan operation tests were performed safely frier to carry out performance test.

• 한국유체기계학회 논문집
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• 제8권6호
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• pp.26-32
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• 2005

1.6 MW class supersonic partial admission impulse turbine has been designed and tested in Korea Aerospace Research Institute for the liquid rocket engine application. The test has been performed using a high pressure air source facility in KARI. For the turbine power absorption, a hydraulic dynamometer has been used. Appropriate similarity relations are used for the determination of test condition. Various settings of turbine pressure ratio and rotational speed are tested to investigate global turbine characteristics. From measured data, parameters related to the turbine design are derived and validated.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 추계학술대회 논문집
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• pp.52-56
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• 2011

Recently, KARI(Korea Aerospace Research Institute) has been developing a modern 11.5m diameter four bladed bearingless main rotor system, and this rotor system can be used for 7,000lb class helicopter. Flexbeam and torque tube can be considered as the key structural components, and large elastic twist of flexbeam induced by pitch control motion of torque tube can influence the nonlinear aeroelastic behavior. In this paper, the dynamic characteristic analysis results of bearingless rotor system were presented. In order to construct a input model and validate the analysis procedures, calculated results using the comprehensive helicopter analysis program CAMRAD II were compared with the measured natural frequencies and lag damping data from small-scale wind tunnel test. Next, the analysis model was extended to a full-scale model, and the dynamic analysis results were presented.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2003년도 춘계학술발표회 논문집
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• pp.271-276
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• 2003

The Moderate Resolution Imaging Spectroradiometer (MODIS) on the Earth Observing System (EOS) of Terra and Aqua satellites, launched in December 1999 and May 2002, has been directly received by Korea Aerospace Research Institute (KARI) ground station facility from July 2002. MODIS scans a swath width of 2330 km that is sufficiently wide to cover Korean peninsular, Yellow and East Sea at once. The MODIS has 36 spectral bands between 0.415 $\mu\textrm{m}$ and 14.235 $\mu\textrm{m}$, i.e., through the visible into the thermal infrared. MODIS has been observed active fires, floods, smoke transport, dust storms, severe storms since February of 2000. The satellite imagery obtained through the MODIS will be utilized for many application such as national territorial management, agriculture, natural environment, atmosphere and ocean, etc. In this study is to introduce various application field of MODIS imagery and data processing system.

• 한국소음진동공학회논문집
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• 제22권2호
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• pp.187-192
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• 2012

Recently, KARI(Korea Aerospace Research Institute) has been developing a modern 11.5 m diameter four bladed bearingless main rotor system, and this rotor system can be used for 7,000 lb class helicopter. Flexbeam and torque tube can be considered as key structural components, and large elastic twist of flexbeam induced by pitch control motion of torque tube can influence the nonlinear aeroelastic behavior. In this paper, the dynamic characteristic analysis results of bearingless rotor system were presented. In order to construct a input model and validate the analysis procedures, calculated results using the comprehensive helicopter analysis program CAMRAD II were compared with the measured natural frequencies and lag damping data from small-scale wind tunnel test. Next, the analysis model was extended to a full-scale model, and the dynamic analysis results were presented.

• 한국항공운항학회지
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• 제12권2호
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• pp.1-15
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• 2004

In this study, we analyze technical requirements for a 50m unmanned airship order to assure safety in the test flight operation. The 50m class unmanned airship developed by Airship Group in Korea Aerospace Research Institute(KARI). The 50m class unmanned airship was developed as a scale-down model of 200m class stratosphere unmanned airship. This study reviews specifications and characteristics of 50m class unmanned airship and develops Airworthiness Requirements on the basis of current effective Aviation Act, Airworthiness standards, and relevant international documents. The developed requirements can be applied to the safety assessment of the 200m class stratosphere unmanned airship.

• International Journal of Aeronautical and Space Sciences
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• 제6권1호
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• pp.89-96
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• 2005

Ducted fans have advantages in noise as well as operational safety aspects compared to conventional tail rotors and are used as an anti-torque system for various classes of helicopters. The final goal of this study is to develop a ducted fan anti-torque system which can replace conventional tail rotors of existing helicopters to achieve safety enhancement and low noise level. In this paper, a conceptual design process and the results are described. Initially, the design requirement and the design parameter characteristics are analysed, and then initial sizing and configuration design are performed. There are several configuration changes due to specific technical reasons in each case. Finally, the required power and the pitch link load are predicted as an initial estimation. The conceptual design technique for the ducted fan in this study can be easily applied to the design of other ducted fans such as the lift fan for unmanned aerial vehicle.