• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.06a
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• pp.390-391
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• 2012

동절기 혹한으로 인해 내륙 수로가 결빙될 경우 수로 운항이 상당 기간 불가능해짐에 따라 경제적 손실이 발생하게 된다. 연안 해운이 주로 발달한 우리나라의 경우 동절기 결빙에 따른 선박 운항 장애에 관한 사례가 많지 않지만, 내륙 수로 운항의 비중이 높고 혹한기가 긴 북유럽과 미국 북부지역에서는 수로 결빙의 메카니즘 및 대처 방안에 대한 연구가 많이 이루어져 왔다. 본 논문에서는 지금까지 밝혀진 주요한 수로 결빙 메카니즘 및 해결 방안에 대하여 소개하였다.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2006.04a
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• pp.327-332
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• 2006

본 연구의 목적은 GIS 공간분석을 이용하여 음영에 따른 노면결빙예상구간을 정량적으로 평가하는데 있다 산악지역의 도로는 절토 및 터널구간이 많아서 겨울철에는 결빙구간이 발생될 우려가 있으며, 이는 교통 안전사고를 크게 야기시킬 수 있다. 따라서 도로의 기본설계에서부터 각 구간에서의 일조 환경 및 노면결빙예상구간을 정량적으로 정확하게 예측할 수 있는 분석이 필요하다. 본 연구에서는 동해고속도로 중 약 29km구간에 대하여 3차원 모델링, 일조 시뮬레이션, 지오데이터베이스 구축, GIS 중첩 기능에 의한 공간분석을 통해 노면결빙 예상구간을 추출할 수 있었다. 연구결과, GIS를 이용할 경우 기상조건 별로 도로의 일조영향에 따른 노면결빙 예상구간을 정량적으로 추출할 수 있었으며, 연구대상지역 중 상당한 구간이 결빙의 위험에 노출되어 있음을 알 수 있었다. 또한 GIS를 이용한 렌더링 기법이 기존의 음영기복 방법보다 정확하며, 3차원 상에서 그림자의 변화를 시각적으로 판단할 수 있음을 알 수 있었다. 향후 본 논문이 도로관련 법제도상의 노면결빙구간에 대한 규정을 제정하는데 크게 이바지할 수 있을 것으로 생각되며, 도로 설치 구조물의 배치 및 도로포장의 종류 등을 고려한 추가적인 음영구간추출 연구가 필요하다고 판단된다.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.391-392
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• 2010

The frozen road is effected as major cause of car accident in winter. Especially, road surface freezing on the highway can lead to fatal accident. The accident by frozen road can effectively reduced by prevent road surface freezing before it frozen as evaluate road surface condition. Therefore, this study installed thermometer in each depth of concrete pavement for evaluate road surface conditions which freezing chronically. The result of this study will be used as preliminary data for predict before freezing.

• Aerospace Engineering and Technology
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• v.5 no.2
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• pp.37-46
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• 2006

The outside environment is very severe while aircraft is cruising. Especially small particle of icing in cold air condition can have negative influence on aircraft performance. If ice particle is attached to leading edge of wing, it can change wing configuration and decrease flight quality. If icing particle is attached to inlet of engine, it can damage compressor blade and have negative influence to aircraft safety. We make icing simulation device with liquid air system for analyzing about variation of engine performance due to incoming of icing to engine.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.04a
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• pp.358-361
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• 2007

Most aircraft cruise in the stratosphere at which temperature is below $-50^{\circ}C$ md, as a result, the surface of aircraft can be iced up. Ice on the wing can change aerodynamic characteristic and results in the deterioration of its performance. Ice on the engine inlet increases the possibility of compressor blade damage and affects the performance and safety of the engine. This paper focused on the development of icing simulation device for analyzing effect of icing on engine performance. Icing simulation tests were conducted with a liquid air system and a icing simulation device and results show that icing could be simulated with this system.

• Aerospace Engineering and Technology
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• v.7 no.2
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• pp.196-204
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• 2008

Modem rotorcraft is required to have the capability to operate in all-weather conditions. Also icing condition is important issue to aircraft safety and certification. And rotorcraft icing research has come a long way during the past few decades. The aircraft icing is the most difficult to handle. So, icing-related accidents, incidents and operating problems still occur regularly in service, despite improvements in design and test techniques. By reviewing icing certification requirement of FAR(Federal Aviation Regulations) and KAS(Korean Airworthiness Standard), this paper describes methods how to demonstrate safety in the flight and consideration of icing when rotorcraft is required TC(Type Certification).

• Journal of Korean Society for Geospatial Information Science
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• v.13 no.4 s.34
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• pp.19-25
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• 2005

This study suggests a method for securing road safety by extracting the expected surface freezing section in planning a route using GIS. When planning a road construction in a mountainous area it is possible to confront surface freezing especially in the wintertime. In addition, it is required assessment data of surface freezing rates in the case of turnkey inspections of newly constructed or expanded roads. Consequently, an analysis method that can quantitatively estimate the surface freezing section and sunshine influence on each section of a road is needed. We can extract the expected surface freezing section which amounted to around 29km of the Donghae highway, with such techniques as three-dimensional modeling, sunshine simulation geographical database construction and spatial analysis using the overlay function of the GIS spatial analysis. This study can be used as a method to assess advance safety which has a direct influence on planning the blueprint that should be approved by a policy maker after efficiently understanding the expected surface freezing section in accordance with hill shade.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.2
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• pp.134-143
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• 2014

A significant degradation in the aerodynamic performance of wind turbine system can occur by ice accretion on the surface of blades operated in cold climate. The ice accretion can result in performance loss, overloading due to delayed stall, excessive vibration associated with mass imbalance, ice shedding, instrumental measurement errors, and, in worst case, wind turbine system shutdown. In this study, the effects of ice accretions on the aerodynamic characteristics of wind turbine blade sections are investigated on the basis of modern CFD method. In addition, the computational results are used to predict the performance of three-dimensional wind turbine blade system through the blade element momentum method. It is shown that the thickness of ice accretion increases from the root to the tip and the effects of icing conditions such as relative wind velocity play significant role in the shape of ice accretion.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.4
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• pp.253-260
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• 2013

Ice accretions on the surface around a rotorcraft air intake can deteriorate the safety of rotorcraft due to the engine performance degradation. The computational simulation based on modern CFD methods can be considered extremely valuable in analyzing icing effects before exact but very expensive icing wind tunnel or in-flight tests are conducted. In this study the range and amount of ice on the surface of anti-icing equipment are investigated for heat-on and heat-off modes. It is demonstrated through the computational prediction and the icing wind tunnel test that the maximum mass and height of ice of heat-on mode are reduced about 80% in comparison with those of heat-off mode.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.11
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• pp.1105-1114
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• 2010

Ice shapes accumulated on the aircraft surfaces are categorized into rime and glaze ice, which are highly dependent on various parameters such as ambient temperature, liquid water contents (LWC), mean volumetric droplet diameter and freestream velocity. In this study, quantitative analyses on the ice accretion have been attempted in a systematical manner and the key findings are as follows. First, the increase of freestream velocity can cause tremendous change in the ice accumulation such as the growth of ice accretion area, ice heading direction and maximum thickness of ice horn. Second, LWC is found to be linearly proportional to the ice accretion area. Third, the effects of ambient temperature on incoming water mass seem to be relatively small in comparison with LWC and freestream velocity. Finally, it was shown that MVD has only a little influence on ice shapes. However, it may increase the ice accretion area by increasing the droplet impacting range.