• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.1083-1087
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• 1996

Bore evacuator which have circular structure of cylindrical form is located at tube, and its function is to evacuate toxic gases generated during firing intervals. Between bore evacuator and bore interior, gas flow field is developed through the nozzles, and the charging and discharging process is formed. By these flow cycle(charging and discharging) the evacuation effect can be generated. This report contains an analyses and results consideration about bore evacuator flowfield.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.572-582
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• 2017

It is definitely important to measure thrust during ground test when developing air-breathing engine, and in case of air-breathing engine, gross thrust should be calculated considering not only the measured thrust but also the force induced by the air flow of engine intake. Also, side thrust like yaw and pitch should be measured and analyzed using multi-component thrust measurement system. Engine performance was accurately evaluated by calculating the gross thrust of air breathing engine precisely which is analyzed from below serial procedure: labyrinth seal isolation, 1-axis gross thrust calculation, develop multi-component thrust measurement system, and side thrust analysis.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2000.11a
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• pp.20-20
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• 2000

2개의 경사 충격파와 하나의 수직 충격파로 초음속 유동을 압축하는 초음속 공기 흡입구의 수치적 연구를 수행하였다. 지배방정식으로는 Navier-Stokes방정식을 사용하였고 난류모델로는 SST 모델을 사용하였다. 지배방정식의 점성항 계산에는 중심차분법을 사용하였고 대류항 계산에는 풍상차분법인 Roe의 FDS기법을 MUSCL기법과 결합하여 이용하였다. 유한 체적법을 이용하여 차분된 방정식은 LU분할 기법을 이용한 완전 내재적 방법으로 2차 정확도 시간 적분으로 비정상 과정의 연구를 수행하였다. 흡입구 배압을 정해주어야 하는 어려움을 해결하기 위해 흡입구 후면에 노즐을 달고 노즐의 면적을 조절하여 배압이 형성되도록 하였다.(중략)

• 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.

• Tuberculosis and Respiratory Diseases
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• v.60 no.5
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• pp.564-570
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• 2006

Toxic gases and soot deposition as a consequence of smoke inhalation can cause direct injury to the upper and lower airways and even to the lung parenchyma. A delay in proper and prompt therapy can be detrimental to critically ill burn patients with an inhalation injury. Therefore, serial chest radiography is an important diagnostic tool for pulmonary complications during treatment. The radiographic findings of the chest include normal, consolidation, interstitial and alveolar infiltrates, peribronchial thickening, atelectasis, cardiogenic and non-cardiogenic pulmonary edema, and a pneumothorax as acute complications of smoke inhalation. In addition, bronchiectasis, bronchiolitis obliterans and pulmonary fibrosis can occur as late complications. We encountered a case of 44-year-old male who presented with acute lung injury after an inhalation injury. He required endotracheal intubation and mechanical ventilation due to respiratory failure. He was managed successfully with conservative treatment. Later, a cavitary lesion of the left upper lobe was observed on the chest radiography and computed tomography, which was complicated by massive hemoptysis during the follow-up. However, the cavitary lesion disappeared spontaneously without any clinical consequences.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.322.1-322
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• 2002

국내외의 반도체 회사의 반도체 제작공정에서 여러 종류의 가스를 흡입하여 웨이퍼의 증착에 이용하게 되는데 각각의 과정에서 요구되는 진공도를 유지하기 위하여 사용되는 것이 드라이 진공펌프이다. 이때 사용되는 질소가스의 흡입압력에 의해 발생되는 진공도의 변화에 따른 진공펌프의 소음 특성을 실험을 통해 분석하였다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.348-349
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• 2000

HF는 주로 음료수와 식수에 의해 폭로되며, 작업자의 경우는 공장 작업과정에서 공기 흡입과 피부 접촉으로 폭로된다. 단기적인 흡입에 의한 폭로는 폐수종 및 자극 등을 주며, 눈과 피부에 직접 폭로시에는 화상과 자극을 준다. 장기간의 폭로는 주로 음료수와 음식에 의해 폭로되며, 공기에 의한 폭로는 코, 인후 및 기관지에 충혈 및 자극을 주고(U. S. EPA, 1989; U. S. EPA, 1993), 식물의 경우에는 잎의 끝이나 가장자리의 변색, 발육 부진 및 병에 대한 저항성 약화 등에 영향을 미치는 것으로 알려져 있다(Cao, 1998). (중략)

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.5
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• pp.426-437
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• 2007

off-design conditions, supersonic air inlets often encounter the problem of aerodynamic instability, called inlet buzz, which causes the significant degradation of the engine performance. An experimental and numerical study was conducted to investigate the phenomenon of supersonic inlet buzz on a generic, axisymmetric, external-compression inlet with a single-surface center-body. It is understood the mechanism of buzz onset as proving that the origin of buzz is the flow choking induced by separation at the intake throat. Also it is observed the intermittent and continuous buzz mode as area ratio varies and understood the transition process through this study. The buzz frequency become to be higher as decreasing the area ratio, but for each area ratio, the frequency of pressure oscillation is the same at all points of intake.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.3
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• pp.97-108
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• 2018

It is definitely important to measure thrust during ground test when developing air-breathing engine, and in case of air-breathing engine, gross thrust should be calculated considering not only the measured thrust but also the force induced by the air flow of engine intake. Also, side thrust like yaw and pitch should be measured and analyzed using multi-component thrust measurement system. Engine performance was accurately evaluated by calculating the gross thrust of air breathing engine precisely which is analyzed from below serial procedure: labyrinth seal isolation, 1-axis gross thrust calculation, develop multi-component thrust measurement system, and side thrust analysis.

• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.4
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• pp.100-108
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• 2006

Experimental study has been a general way to evaluate inlet and exhaust duct performances, but this is not only costly but also time consuming. Computational simulation is hence replacing experimental study and consequently time and cost saving. This paper therefore aims to investigate typical component performance of the intake and exhaust ducts using 3D representation. In this study a specific inlet and exhaust was modeled and analyzed to estimate its losses and flow field using computational fluid dynamic program with flow visualization capabilities. A process that requires geometry data to be modeled. That allowed for possibility of design trade off in designing phase. Installed performance of a specific turbo shaft engine was finally evaluated with the estimated inlet, exhaust and other accessories losses.