• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.463-466
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• 2010

A scramjet engine intake model was tested with a storage air heater type hypersonic wind tunnel. In test results, there is no large performance change with the variation of the sidewall configurations. In the isolator performance analysis, pressure distribution of oblique shock train and normal shock train was observed. Unstart limit of the model was also confirmed.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.4
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• pp.337-345
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• 2008

this study, three dimensional surface pressure distributions of SWIM whose main wing has NACA4412 airfoil with NACA0012 flaps were experimentally measured by pressure sensitive paint. Surface pressures on suction and pressure sides of the wing were measured by changing an angle of attack at a Reynolds number of 3.1x105 in KARI 1m subsonic wind tunnel. The experimental results showed that as an angle of attack increases minimum pressure region on a suction side moved from the wing root to the tip and low pressure region around trailing edge of the wing tip which causes wing tip vortex was observed. Although low pressure region at the tip still observed at an angle of attack 15 deg., other area on a suction side showed flat pressure distribution in a span-wise direction. It was also observed that the mean value of pressure coefficients was about 0.077 through a comparison between PSP and pressure taps at the same test conditions.

• Composites Research
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• v.33 no.4
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• pp.205-212
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• 2020

In this study, HfC was coated on two types of carbon/carbon composites coated with SiC by vacuum plasma spraying(VPS). The experiment was performed using a plasma wind tunnel with heat flux of 5.06 MW/㎡ for 120 s heat flux before and after the coating. The mass ablation rate was calculated through the mass change before and after the test, and the length change was measured by using calipers and high speed camera. The oxidation/ablation behavior were observed by FE-SEM with EDS analysis of the specimens cross section. The plasma wind tunnel test results showed that the coated specimens had low weight loss and length change, and high oxidation/ablation resistance. However, two types of the specimens tested under the same conditions were different in the ablation behavior and ablation rate, and it was evaluated that the cylindrical type had higher oxidation/ablation resistance.

• 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 KSME
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• v.33 no.10
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• pp.861-870
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• 1993

여기서는 차량의 구동 성능을 예측하기 위하여 대우자동차에서 최근에 개발한 프로그램에 대하여 설명하고자 한다. 이 프로그램의 특징으로는 기능의 다양화 및 사용의 편리함을 들 수 있다. 이 프로그램은 수동 및 자동 변속기 장착 차량의 가속 성능과 연비를 예측할 수 있게 하였다. 정속 주행 시험과 같이 일정 속도의 주행 상태와, 가속 성능 시험에서와 같이 정해진 드로틀개도 변화에 따르는 주행 상태뿐 아니라, LA-4모두, Tokyo-10모드와 같이 시간에 따라 변화하는 속 도에 따른 주행 상태의 시뮬레이션도 가능하게 하였다. 주행 저항 계산방법으로는 풍동시험을 이용한 방법뿐 아니라 타행 (Coastdown) 시험을 이용하는 방법을 추가하였다. 예측 결과의 정 확도에 별로 영향을 주지않는 부분은 단순화시켜 모델링함으로써 입력 데이터 수를 작게 하였고 이로 인하여 사용자의 편리성을 높게 하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1272-1278
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• 2014

In this experimental study for the current growing offshore wind, a wind tunnel test was conducted to examine the performance of the vertical-type cross-flow wind turbine power generation system. Due to the limited size of the test section of the wind tunnel, the inlet guide vane of the original wind power generation was scaled down to about 1/5 and the turbine impeller diameter was also reduced to 1/2 of the prototype impeller. The number of the impeller blade is another important parameter to the output power of the wind power generation system and the number was varied 8 and 16. From the analysis of the experimental result, the output brake power of the model wind turbine was measured as 278watts with the 16-blade at 12 m/s of the rated wind speed and the rated brake power of the prototype wind turbine is calculated to 3.9kW at the rated operating condition.

• Journal of Advanced Navigation Technology
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• v.27 no.5
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• pp.519-527
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• 2023

Air-launch means launching from aircraft such as fighter jets, and has various advantages, such as cost reduction and less environmental/weather impact during launch. However, there are no air-launch satellite in Korea. Examining air-based launch satellite and anti-satellite missiles operated and developed by foreign private companies and various countries confirmed the necessity of domestic research and development. In South Korea, various research activities, including satellite launch system design and development approaches for different launch platforms, have been carried out mainly by academia. Development of upward maneuver air launch technology which is launched in the air when the aircraft is moving upward is suggested. Additionally, an introduction to wind tunnel tests for safety separation verification is provided. A new concept for a test facility has been suggested to conduct drop tests.

• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.1
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• pp.77-87
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• 2022

In order to perform the scramejt engine intake ground test using the Scramjet Engine Test Facility(SETF) of the Korea Aerospace Research Institute. we introduced the test availability check procedure that is generally conducted. The design process of the newly manufactured Mach 5 nozzle for the scramjet intake test was summarized, a device for checking the core flow distribution of the nozzle was explained, and the core flow test analysis results were written. Through a series of test results, it was confirmed that the intake was located in the new Mach 5 nozzle core.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.584-587
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• 2011

An internal flow aerodynamic test was performed for a Mach 5 scramjet engine. The test was done without fuel injection, as a preliminary test for the combustion test. Test engine is an engineering model with intake cross-section of $70mm{\times}200mm$ and total length of 1.7m. Test facility is a blowdown-type, high enthalpy, hypersonic facility. 19 pressures were measured through the holes on the model surface along the engine internal flow passage. It was found that the facility start is possible, and also supersonic flow is maintained inside the engine.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.762-767
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• 2008

Estimated values for maximum lift coefficients of a light airplane, ChanGong-91, derived from an analytical method using a test database, a computational fluid dynamic method, a wind tunnel test, and a flight test are compared. The DATCOM method and VSAERO code are applied as the analytical method and the computational fluid dynamic method, respectively, in order to estimate the maximum lift coefficients of a light airplane. The wind tunnel test is conducted using a 1/14.5 scaled model installed in a closed circuit type wind tunnel. For the flight test approach, the wings-level power-off stall tests are performed to obtain the maximum lift coefficients. As a point of reference for the flight test results of the maximum lift coefficients, the differences of both estimates derived from the DATCOM method and the wind tunnel test data are smaller than those derived from VSAERO.