• Title/Summary/Keyword: wind-speed change

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Variability of Future Wind and Solar Resource Over the Korean Peninsula Based on Climate Change Scenario (기후변화 시나리오에 근거한 한반도 미래 풍력·태양-기상자원 변동성)

  • Byon, Jae-Young;Kim, Yumi;Choi, Byoung-Choel
    • New & Renewable Energy
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    • v.10 no.2
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    • pp.29-39
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    • 2014
  • This study examines the future variability of surface wind speed and solar radiation based on climate change scenario over the Korean Peninsula. Climate change scenarios used in this study are RCP 4.5 and 8.5 with a 12.5 km horizontal resolution. Climate change scenario RCP 4.5 and 8.5 reproduce the general features of wind speed over the Korean Peninsula, such as strong wind speed during spring and winter and weak wind speed during summer. When compared with the values of wind speed and solar radiation of the future, they are expected to decrease current wind and solar resource map. Comparing the resource maps using RCP 4.5 and 8.5 scenarios, wind speed and solar radiation decrease with increasing greenhouse gas concentration. Meteorological resource maps of future wind and solar radiation should be improved with high resolution for the industrial application.

Air Corridor Planning Strategy based on the Wind Field and Air Corridor Simulation - A Case Study of Pan-Gyo New Town Development Area - (바람통로 예측모델링을 통한 바람통로 계획전략 - 성남판교 신도시 개발지구를 중심으로 -)

  • 황기현;송영배
    • Journal of the Korean Institute of Landscape Architecture
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    • v.31 no.5
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    • pp.43-57
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    • 2003
  • This paper presents the air corridor planning strategy based on simulation with MUKLMO_3 (Micro-scale Urban Climate Model) to investigate the wind field and air corridor caused by the land-use change of the New Town Development Area in Pan-Gyo. In the first part, the most frequently observed wind field in the New Town Development Area was measured and used as an initial value to simulate a more realistic wind field and air corridor. Several experiments with different initial values of wind fields were carried out to investigate the wind field change affected by the New Town Development. The results show the features of the wind field of the neutral stability condition in the urban canopy layer with a high resolution near the ground. The wind speed is weakened at this level due to the New Town Development. It was found that the wind field and air corridor are influenced by the land-use change. After the development of the New Town, the speed of the wind field decreased and the main wind directions and air corridor changed. In this study, this model is found to be a useful tool for evaluating air corridor and change of wind field in speed and direction.

Wind load equation for electric power facility design (전력시설물 설계를 위한 풍하중 산정식)

  • Choi, Sang-Hyun;Seo, Kyung-Seok;Lee, Su-Hyung
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.42-54
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    • 2009
  • The wind load equation for the design of electric power facilities such as electrical pole in railroad is based on the maximum wind velocity without considering regional difference in wind velocities. Also, the use of a different equation to highspeed railroad and the possibility of higher wind speed due to climate change claims a new design equation. In this paper, a wind load equation based on wind speed measurement data to date, which is applicable to both conventional and highspeed railroad is proposed. The proposed equation considers the regional differences in wind speed for economic and effective design, and the possibility of higher wind speed due to climate change.

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Sensitivity Analysis of the Atmospheric Dispersion Modeling through the Condition of Input Variable (입력변수의 조건에 따른 대기확산모델의 민감도 분석)

  • Chung Jin-Do;Kim Jang-Woo;Kim Jung-Tae
    • Journal of Environmental Science International
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    • v.14 no.9
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    • pp.851-860
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    • 2005
  • In order to how well predict ISCST3(lndustrial Source Complex Short Term version 3) model dispersion of air pollutant at point source, sensitivity was analysed necessary parameters change. ISCST3 model is Gaussian plume model. Model calculation was performed with change of the wind speed, atmospheric stability and mixing height while the wind direction and ambient temperature are fixed. Fixed factors are wind direction as the south wind(l80") and temperature as 298 K(25 "C). Model's sensitivity is analyzed as wind speed, atmospheric stability and mixing height change. Data of stack are input by inner diameter of 2m, stack height of 30m, emission temperature of 40 "C, outlet velocity of 10m/s. On the whole, main factor which affects in atmospheric dispersion is wind speed and atmospheric stability at ISCST3 model. However it is effect of atmospheric stability rather than effect of distance downwind. Factor that exert big influence in determining point of maximum concentration is wind speed. Meanwhile, influence of mixing height is a little or almost not.

Verification of Speed-up Mechanism of Pedestrian-level Winds Around Square Buildings by CFD

  • Hideyuki Tanaka;Qiang Lin;Yasuhiko Azegami;Yukio Tamura
    • International Journal of High-Rise Buildings
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    • v.11 no.4
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    • pp.301-314
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    • 2022
  • Various studies have been conducted on pedestrian-level wind environments around buildings. With regard to the speed-up mechanism of pedestrian-level winds, there are references to downwash effect due to the vertical pressure gradient of boundary layer flow and venturi effect due to flow blocking by the building. Two factors contribute to increase or decrease of downwash effect: change in twodimensional / three-dimensional air flow pattern (Type 1) and change in downwash wind speed due to building size that does not accompany change in airflow pattern (Type 2). Previous studies have shown that downwash effect has a greater influence in increasing or decreasing the area of strong wind than venturi effect. However, these considerations are derived from the horizontal mean wind speed distribution at pedestrian level and are not the result of three-dimensional flow field around the building. Therefore, in this study, Computational Fluid Dynamics using Large Eddy Simulation were performed to verify the downwash phenomena that contributes to increase in wind speed at pedestrian level.

The impact of artificial discrete simulation of wind field on vehicle running performance

  • Wu, Mengxue;Li, Yongle;Chen, Ning
    • Wind and Structures
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    • v.20 no.2
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    • pp.169-189
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    • 2015
  • To investigate the effects of "sudden change" of wind fluctuations on vehicle running performance, which is caused by the artificial discrete simulation of wind field, a three-dimensional vehicle model is set up with multi-body dynamics theory and the vehicle dynamic responses in crosswind conditions are obtained in time domain. Based on Hilbert Huang Transform, the effects of simulation separations on time-frequency characteristics of wind field are discussed. In addition, the probability density distribution of "sudden change" of wind fluctuations is displayed, addressing the effects of simulation separation, mean wind speed and vehicle speed on the "sudden change" of wind fluctuations. The "sudden change" of vehicle dynamic responses, which is due to the discontinuity of wind fluctuations on moving vehicle, is also analyzed. With Principal Component Analysis, the comprehensive evaluation of vehicle running performance in crosswind conditions at different simulation separations of wind field is investigated. The results demonstrate that the artificial discrete simulation of wind field often causes "sudden change" in the wind fluctuations and the corresponding vehicle dynamic responses are noticeably affected. It provides a theoretical foundation for the choice of a suitable simulation separation of wind field in engineering application.

A Study on the Change of Wind Speed in South Korea: In Case of January and August (한국에서 풍속 변화에 관한 연구 -1월과 8월을 대상으로-)

  • Lee, Seung-Ho
    • Journal of the Korean Geographical Society
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    • v.47 no.3
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    • pp.347-358
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    • 2012
  • This study aimed to investigate the change of wind speed during winter and summer seasons for 50 years(1961-2010). It were analyzed the mean wind speed, maximum wind speed, windy days and storm days on January and August of 13 weather stations in South Korea. The mean wind speed was decreased in the coastal region(Busan, Jeju, Ulsan, Pohang) in winter and summer seasons. Also it was similar to windy day. The relationship between wind speed and mean temperature has negative correlation in winter season. The relationship is low in summer season. The number of windy day and storm day has negative relation with monthly mean temperature.

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Long Term Variation Trend of Wind and its Impact Upon Wind Power Generation in Taiwan

  • Na, Wang;Quan, Wan;Sheng, Su
    • Journal of Electrical Engineering and Technology
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    • v.9 no.3
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    • pp.782-788
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    • 2014
  • Wind power generation has been viewed as a promising renewable energy to meet challenge of climate change. However, wind power is susceptible to climate change because previous investigation shows there are declining trends of the land surface wind speeds over middle and lower latitudes. Since long term variation trends is notably different from inter-annual random variation and could have notable impact on wind farm from planning perspective, observed meteorological data of Taiwan is investigated to find out long term variation trends of wind speed and its impact on wind power generation. It is discovered that wind speed in majority of stations in west coast of Taiwan have ascending trends while that of all investigated stations in east coast have descending trends. Since east of Taiwan is not suitable for wind power development for its higher likelihood suffering Typhoons and most of established wind farm locate in west coast of Taiwan, it is speculated that long term variation trend of wind do not have notable negative impact on wind power generation in Taiwan.

Non-stationary statistical modeling of extreme wind speed series with exposure correction

  • Huang, Mingfeng;Li, Qiang;Xu, Haiwei;Lou, Wenjuan;Lin, Ning
    • Wind and Structures
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    • v.26 no.3
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    • pp.129-146
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    • 2018
  • Extreme wind speed analysis has been carried out conventionally by assuming the extreme series data is stationary. However, time-varying trends of the extreme wind speed series could be detected at many surface meteorological stations in China. Two main reasons, exposure change and climate change, were provided to explain the temporal trends of daily maximum wind speed and annual maximum wind speed series data, recorded at Hangzhou (China) meteorological station. After making a correction on wind speed series for time varying exposure, it is necessary to perform non-stationary statistical modeling on the corrected extreme wind speed data series in addition to the classical extreme value analysis. The generalized extreme value (GEV) distribution with time-dependent location and scale parameters was selected as a non-stationary model to describe the corrected extreme wind speed series. The obtained non-stationary extreme value models were then used to estimate the non-stationary extreme wind speed quantiles with various mean recurrence intervals (MRIs) considering changing climate, and compared to the corresponding stationary ones with various MRIs for the Hangzhou area in China. The results indicate that the non-stationary property or dependence of extreme wind speed data should be carefully evaluated and reflected in the determination of design wind speeds.

A Study on the Observation of the Typhoons that Affected Southeastern Region of the Korean Peninsula (한반도 동남권역에 영향을 미친 태풍 관측 연구)

  • Jung, Woo-Sik;Park, Jong-Kil;Kim, Eun-Byul
    • Journal of Environmental Science International
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    • v.20 no.9
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    • pp.1191-1203
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    • 2011
  • In case of Typhoon Dianmu, the temperature, wind speed, wind direction and the rainfall per hour changed dramatically when the center of the typhoon passed through Gimhae. Such a change was commonly found in the regions where the center of the typhoon passed through but almost not in the regions far away from it. For example, in the case of Typhoon Malou where the center of the typhoon was far away from the observation site, such a phenomenon was not observed. The analysis of the vertical observation data showed that there was a little change in the wind speed and wind direction in the vertical direction in the case of Typhoon Dianmu of which center passed through Gimhae. There was a great change in the wind speed according to the height in the lower atmosphere just before the center of the typhoon approached the region. When the center of the typhoon was passing through the region, the vertical wind speed was decreased. However, the wind speed was rapidly increased again after the center of the typhoon had passed through the region. Unlike the Dianmu, the difference in the wind speed and wind direction between the upper layer and lower layer of the atmosphere was relatively great in the case of Malou.