• Wind and Structures
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• 제29권3호
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• pp.149-161
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• 2019

When a railway vehicle runs in crosswinds, the unsteady aerodynamic forces acting on the train induced by the vehicle speed, crosswind velocity and local landforms are a common problem. To investigate the dynamic performance of a railway vehicle due to the influence of unsteady aerodynamic forces caused by local landforms, a vehicle aerodynamic model and vehicle dynamic model were established. Then, a wind-loaded vehicle system model was presented and validated. Based on the wind-loaded vehicle system model, the dynamic response performance of the vehicle, including safety indexes and vibration characteristics, was examined in detail. Finally, the effects of the crosswind velocity and vehicle speed on the dynamic response performance of the vehicle system were analyzed and compared.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.133-138
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• 2010

This paper describes on aerodynamic characteristics of pantograph system for Next generation high speed train(HEMU-400). The pantograph which supports electric power is located on the roof. Because of this, it generate high drag, severe acoustic noise and vibration which induced unstable flow due to complex configuration. Therefore, the design of high efficient pantograph needs to increase operational speed. In this research, wind tunnel tests were performed to design a high efficient pantograph system using 1/4 scaled model which were KTX-II pantograph, single arm pantograph and periscope type pantograph with square cylinder shape panhead and optimized shape panhead. For real operational condition, flow directions were adapted by rotation of pantograph. From this results of wind tunnel, it is checked that the pantograph with optimized panhead and single arm type or periscope type has better aerodynamic performance. In addition, lift control device and spoiler in pantograph were tested to investigate the validity of application.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.84-87
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• 2008

In order to maximize the effect of installing screen door system while to minimize the problems in an initial stage of introduction, it is strongly required to research an optimum installation solution in connection with ventilation and disaster prevention system alongside with safety structure analysis of screen door in respect to train-induced wind, as well as to develop the criteria for the operation after the installation. This paper presents the results of study to develop the optimum design technology in urban railway equipped with platform screen door systems.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1480-1486
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• 2011

지하철 승강장의 스크린도어가 설치되기 전에는 승강장을 통해 환기되던 공기가 스크린 도어가 설치된 후에는 터널 내부에 정체되면서 미세먼지에 의한 환경이 더 악화되고 있는 실정이며, 터널환기구가 터널에 정체된 공기의 유일한 순환구로 이용되고 있다. 스크린 도어는 기존 터널환기시스템을 설계할 때 고려되었던 사안은 아니었으며, 지하철 운행 시 스크린도어 설치로 인한 지하 터널 속에서의 공기역학적 변화는 매우 클 것이다. 그러나 지하철이 통과하는 공간인 터널환기에 대한 연구는 미미한 수준이다. 이에 열차가 지하 터널 구간을 운행할 때 발생하는 열차풍에 의한 기류속도를 측정하고, 전철구간의 자연 환기구를 통한 기류의 유입 및 유출 특성을 정량적으로 평가하여 대표적인 기류패턴을 추출함으로써 향후 지하 터널 신설 및 환기 설비 설계에 따른 기초 자료를 제공하고자 한다.

• Asian Journal of Atmospheric Environment
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• 제2권1호
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• pp.60-67
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• 2008

The spatial limitations of urban environments in general lead to invention and design of a wide range of underground transportation systems such as subways, underground roads and paths, etc. Among them, the application of subway systems in metropolitan cities is most commonly observed to ease those confronted difficulties on this purpose. It in turn leaves passengers and workers to be exposed to indoor air potentially polluted by various sources existing in this underground environment. Specifically when considering the IAQ in a subway station, there exist many IAQ-related parameters to be counted either as individual or as integrated exposures. In this study, a model system has been developed to manage the general IAQ in a subway station. Field survey and $CO_2$ measurements were initially conducted to analyze and understand the relationship between the indoor and outdoor air quality while considering the internal pollution sources such as passengers, subway trains, etc. The measurement data were then employed for the model development with other static information. For the model development, the algorithm of simple continuity was built and applied to model the subway IAQ concerned. In this paper, the recent updated draft version of model developed will be reported and demonstrated.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제36회 춘계학술대회논문집
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• pp.363-366
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• 2011

마하 2의 초음속 풍동 장치에서 벤트 혼합기를 사용하여 혼합 연소실험을 수행하였다. 혼합실험에서는 헬륨을 사용하였고, 연소실험에서는 수소와 플라즈마 토치를 사용하여 연소 특성을 연구하였다. 혼합실험에서는 벤트 혼합기에 의해 수직분사임에도 불구하고 후류 혼합층에 많은 연료가 잔존하였다. 연소 실험의 경우 낮은 온도의 초음속 유동에서 플라즈마 토치를 사용한 점화와 연소되지 않은 연료-공기 혼합물의 충격파 유도 연소가 후류 영역에서 발생하였다. 열질식이 일어난 경우, shock train이 발생하며 이는 연소기내 연소 불안정성을 유도한다.