Article
Environmental Sciences
Marcos Paulo Araujo da Silva, Andreu Salcedo-Bosch, Francesc Rocadenbosch, Alfredo Pena
Summary: We reexamine two recent methodologies, the 2D method and Hybrid-Wind (HW), based on Monin-Obukhov Similarity Theory (MOST), which aim to estimate Obukhov length, friction velocity, and kinematic heat flux within the surface layer using wind-speed profile measurements. Both methods are compared using synthetic and observational data. A procedure to generate synthetic noise-corrupted wind profiles is also presented. The 2D algorithm outperforms the HW method in estimating the three parameters, making it a prominent method for surface-layer parameter estimation.
Article
Multidisciplinary Sciences
Huiwen Zhang, Zhen Wu, Jing Hu, Zhiping Zhang, Bin Xiao, Jianping Ma
Summary: Sand flux is a key factor in determining the migration of sand dunes and erosion of the surrounding environment. Studies have shown that factors such as air viscosity and wind velocity can influence the distribution of sand flux. In crescent-shaped sand dunes, wind field velocity and sand flux are higher on the leeward side, and increasing dune height leads to an increase in turbulent intensity on the leeward side.
SCIENTIFIC REPORTS
(2021)
Article
Geography, Physical
Zhong Peng, Ronglin Tang, Yazhen Jiang, Meng Liu, Zhao-Liang Li
Summary: This study presented a practical method for global estimates of 500m daily z0(m) using machine learning techniques, wind profile equation, observations, and MODIS data. The random forest model outperformed deep neural network and convolutional neural network models, showing high accuracy in reproducing daily z0(m) across all land cover types. These results can assist in improving the simulation of momentum, water, and energy transfer between land and atmosphere, enhancing the development of high-resolution land surface and Earth system models.
ISPRS JOURNAL OF PHOTOGRAMMETRY AND REMOTE SENSING
(2022)
Article
Engineering, Civil
Claudio Mannini, Tommaso Massai, Andrea Giachetti, Alessandro Giusti
Summary: This study focuses on the aerodynamic loads on offshore wind turbine towers in group arrangements on port quaysides, proposing an engineering solution based on discontinuous surface roughness to simulate high Reynolds number conditions. The experiments show regular behavior for towers in double-row groups and more complexity for heavily loaded single-row groups.
JOURNAL OF WIND ENGINEERING AND INDUSTRIAL AERODYNAMICS
(2023)
Article
Geosciences, Multidisciplinary
Jiaqi Liu, Reiji Kimura, Mami Miyawaki, Toshihiko Kinugasa
Summary: The study found that plant shape and coverage have an impact on sand accumulation amount, roughness length, and blown-sand flux. Cone and inverted truncated cone-shaped plants exhibit strong inhibitory effects on blown-sand flux, while cylindrical plants have a strong inhibitory effect on blown-sand flux at greater heights.
Article
Green & Sustainable Science & Technology
Fang Wang, Shixiao Liu, Yujia Jiang, Weijia Duan
Summary: This article investigates the wind and sand protection effect of sand barriers on expressways using numerical simulation and field research. The study reveals the impact of different heights and spacing on the wind and sand flow field distribution. The results suggest that controlling the height and spacing of sand barriers is crucial for their protective performance.
Article
Geosciences, Multidisciplinary
Christel Bouet, Mohamed Taieb Labiadh, Caroline Pierre, Saad Sekrafi, Thierry Henry des Tureaux, Mohsen Ltifi, Gilles Bergametti, Beatrice Marticorena, Amadou Abdourhamane Toure, Jean Louis Rajot
Summary: This study conducted an experimental field campaign in a barley field in southern Tunisia to investigate the roles of meteorology, surface properties, and human practices in wind erosion over croplands. The results showed that wind erosion fluxes mainly occurred between mid-May and November, which was influenced by the seasonal cycle of barley crop, land management, and meteorological conditions. The study emphasizes the importance of considering the joint seasonality of meteorological parameters, vegetation cover, and human practices in studying wind erosion, as neglecting any of these parameters can lead to overestimations or underestimations by models.
Article
Chemistry, Multidisciplinary
Dianyi Guo, Shuo Jiang, Yunfeng Zou, Xuhui He, Qingkuan Liu
Summary: This paper introduces a new type of wind guide barrier (WGB), and conducts wind tunnel experiments to study the key parameters of three types of WGB and their effects on the aerodynamic characteristics of a high-speed train and blunt body box girder system, as well as the wind field on the bridge deck. The results show that the main factor affecting the windproof performance of the WGB is the shielding effect. The WGB can achieve similar wind pressure distribution on the train as a vertical wind barrier, while reducing resistance and increasing the aerodynamic coefficient on the train.
APPLIED SCIENCES-BASEL
(2023)
Article
Ecology
Bruna R. F. Oliveira, Jan J. Keizer, Thomas Foken
Summary: This study analyzes the impacts of two storms in December 2019 on a maritime pine plantation in central Portugal, including changes in aerodynamic characteristics and effects on turbulent fluxes. The windthrow only had a minor effect on the turbulent fluxes, but it significantly altered the footprint area of the flux tower.
Article
Geosciences, Multidisciplinary
Yuanfeng An, Jianjun Cheng, Lusheng Ding, Boyu Chen, Li Gao, Jia Lei, Benteng Ma, Zhipeng Zhen
Summary: This study focused on the reed sand barrier protection project of the Xinjiang segment of Golmud-Korla railway. Using field monitoring, wind tunnel testing, and numerical simulation, the study revealed the characteristics of flow field evolution and sand accumulation distribution under the control of three-row sand barrier spacing. The optimal spacing of three-row reed sand barriers was determined through design exploration optimization analysis.
Article
Geosciences, Multidisciplinary
Chunlai Zhang, Yixiao Yuan, Xueyong Zou, Hongtao Wang, Qing Li, Zhenting Wang, Rende Wang
Summary: This study investigated the aerodynamic characteristics of different land surface types in northern China and analyzed the effects of surface roughness elements on the airflow. The results showed that the roughness length, wind speed pulsation, turbulence intensity, and drag coefficient varied among different land surfaces. Furthermore, the shelter capability of flexible roughness elements increased with increasing wind speed, while that of rigid roughness elements decreased.
Article
Geosciences, Multidisciplinary
Benli Liu, Jianjun Qu, Lihai Tan, Zhishan An, Hongtao Wang, Tao Wang, Qingjie Han
Summary: This study quantifies the movement of coral sand by wind tunnel measurement and compares it to quartz sands from an inland desert. The results show that coral sands have different movement characteristics, including increased threshold wind speed, total rate, and exponential decrease in sand concentration with height. These findings contribute to the evaluation of the influence of aeolian processes on the landform of coral islands.
Article
Engineering, Mechanical
Rodolfo Curci Puraca, Bruno Souza Carmo
Summary: This study analyzed various strategies for dealing with blade degradation in wind turbine design phase. The results showed that for a fixed speed turbine, designing rough blades is more effective when the turbine operates with rough blade surface for 34.95% or more of its lifespan; whereas for a variable speed turbine, designing rough blades is better only when the turbine works with rough blade surface for 50.59% or more of its lifespan.
JOURNAL OF THE BRAZILIAN SOCIETY OF MECHANICAL SCIENCES AND ENGINEERING
(2021)
Article
Environmental Sciences
Ye Liu, Weidong Guo, Huilin Huang, Jun Ge, Bo Qiu
Summary: This study provides global estimates of aerodynamic parameters from 1982 to 2017 based on remote-sensed data, showing significant positive trends in canopy height, displacement height, and roughness length associated with Earth greening. The findings emphasize the importance of considering changes in LAI, canopy height, and aerodynamic parameters when evaluating ecosystem effects on climate change.
REMOTE SENSING OF ENVIRONMENT
(2021)
Article
Geosciences, Multidisciplinary
Lihai Tan, Jianjun Qu, Tao Wang, Kai Zhang, Zhishan An
Summary: Wind-blown sand over Gobi can cause severe sand abrasion. The vertical flux profiles, especially that of the kinetic energy (KE), determine the erosion intensity. The non-monotonic KE flux profiles primarily emerged during periods of strong transport and were mainly caused by large saltating sand particles due to their high KE as they rebounded from grain-bed collision.
GEOPHYSICAL RESEARCH LETTERS
(2021)