Abstract
This paper presents the wind tunnel test and numerical simulation on umbrella-shaped tensioned membrane
structures to investigate the effects of both high wind velocity and various wind direction of typhoon on their aerodynamic
behavior. Finite element models are also developed and benchmarked to further investigate the effects on rise-to-span ratio, wind
attack angle, and pretension. Results from the experimental tests and finite element analyses show that: (i) the turbulence
buffeting in the leeward surface is significant with large displacement responses, especially with the 0° wind direction, large
wind attack angle and high rise-to-span ratio; (ii) Non-Gaussian characteristics become remarkable with increasing skewness
and kurtosis, which may be contributed by the high-level turbulence intensity in typhoons; and (iii) the effects of rise-to-span
ratio, wind attack angle and pretension are proved more significant, which should be considered in the wind-resistance design of
membrane structures in typhoons.
Key Words
aerodynamic behavior; coupled FSI simulation; typhoons; umbrella-shaped membrane structures; wind tunnel test
Address
Dong Li:1)College of Civil Engineering, Fuzhou University, Fuzhou 350116, China
2)Key Laboratory of Fluid and Power Machinery (Xihua University), Ministry of Education, Chengdu 610039, China
3)School of Advanced Manufacturing, Fuzhou University, Jinjiang 362251, China
Zhou Zhang:School of Advanced Manufacturing, Fuzhou University, Jinjiang 362251, China
Yi Qiu:College of Civil Engineering, Fuzhou University, Fuzhou 350116, China
Zhiwei Chen:Kaihui Group Co., Ltd, Putian 351100, China
Zhichao Lai:College of Civil Engineering, Fuzhou University, Fuzhou 350116, China
Abstract
Wind spectrum models are pivotal in various fields, ranging from structural engineering to meteorology. This
review meticulously examines the origination, development, and applications of five prominent theoretical models of wind
spectra. Each model is scrutinised for its analytical expressions and underlying assumptions, providing a comprehensive
understanding of their evolution over time. The journey commences with a historical overview, tracing the inception of these
models and the seminal contributions that shaped their formulation. Subsequently, the development trajectory of each model is
delineated, highlighting key advancements and refinements made in response to empirical observations and theoretical insights.
In order to assess the practical efficacy of these models, real-field data has been subjected to spectral analysis using both Welch
and FFT methods. Through rigorous comparative analysis, the performance of each spectrum model has been evaluated in terms
of its ability to capture the complex dynamics of wind behaviour across different spatial and temporal scales. Moreover, this
research highlights the evolution of wind spectrum modelling by elucidating the field's contemporary trends and emerging
paradigms. Insights gleaned from this analysis deepen our understanding of atmospheric dynamics and inform the development
of more robust and accurate wind spectrum models for diverse engineering and environmental applications. This review is a
comprehensive compendium of wind spectrum models, offering invaluable insights into their historical development, theoretical
underpinnings, practical applicability, and future prospects.
Key Words
power spectral density; statistical theory; wind response spectrums; wind turbulence
Address
Taniya Saha and Somnath Karmakar:Department of Civil Engineering, National Institute Technology Durgapur, India-713209
Abstract
Offshore floating photovoltaic (PV) is the technological commanding heights of the future development of the
photovoltaic industry, especially under the action of extreme weather such as typhoons and huge waves, the flow field
mechanism of offshore large-span floating flexible PV arrays is more complex, and there is a lack of effective offshore floating
PV wind load prediction models in the relevant design codes of flexible PV in the world. Taking a typical flexible PV key
demonstration project as the research object, a three-dimensional mesoscale Weather Research and Forecasting (WRF) -
Simulating Waves Nearshore (SWAN) - Finite-Volume Coastal Ocean Model (FVCOM) real-time two-way coupling simulation
method based on Mapped Contact Interface (MCT) coupler was proposed, a meso/small-scale nested typhoon-wave-flow
numerical pool of PV array was established, the wind load distribution characteristics of single-row floating flexible PV were
studied, the driving mechanism of inter-row flow field of floating large-span flexible PV array was compared and analyzed, and
finally the value model of the lift/drag coefficient of PV array under extreme wind conditions was established. The results show
that the average wind pressure of single-row floating flexible PV presents trapezoidal and L-shaped distribution rules under
different wind direction angles, and the temporal instability and spatial discontinuity in the low wind speed area of the floating
flexible PV array and the complex and disordered alternating vortex phenomenon are the main reasons for the inter-row
interference, and the proposed fitting formula of two-dimensional lift/drag coefficient can encompass the extreme value of the
actual wind pressure, and the maximum error is controlled within 10 %, which can provide a reference for the prediction of the
design value of this kind of floating flexible PV wind load.
Key Words
coupled typhoon-wave-current simulation; flow field driving mechanism; meso/small scale nesting; offshore
floating flexible photovoltaic; wind load extreme value model
Address
Wencai Wang:Department of Aerodynamics, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
Shitang Ke:1)Department of Aerodynamics, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
2)Department of Civil and Airport Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China
Wei Yu:Department of Civil and Airport Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China
Yujiang Zhang:Department of Civil and Airport Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China
Zhefeng Pan:Das Solar Co., Ltd., Quzhou 324000, China
Tingrui Zhu:Department of Civil and Airport Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China
Xiuyong Zhao:National Energy Group Science and Technology Research Institute Co., Ltd., Nanjing 210031, China
Abstract
By using a computational procedure of three-dimensional aerostatic and aerodynamic stability analysis of long-span
bridges, the dynamic characteristics, structural stability including the aerostatic and aerodynamic stability are firstly analyzed for
a three-tower cable-stayed bridge with main spans of 1400 meters, the parametric analysis is then conducted, and finally a
favorable structural scheme of the example bridge is proposed and confirmed numerically. The results show that long-span
three-tower cable-stayed bridge has significant flexibility with less vertical and especially horizontal stiffness, and is sensitive to
the transverse wind action; long-span three-tower cable-stayed bridge exhibits a coupled aerostatic instability mode of vertical
bending and torsion; the aerodynamic stability is worse than the aerostatic stability for long-span three-tower cable-stayed
bridge, the flutter critical wind speed is significantly reduced by the static wind action, and thus the aerostatic effect must be
involved in the aerodynamic stability analysis; the best wind stability is obtained for the example bridge as 2 auxiliary piers are
set in each side span and their centerline differs from the side piers by 0.4 times the side span length, the center-to-side tower
height ratio is 1.3, the tower height-to-span ratio is 1/5, 4 pairs of crossing cables are set at midspan of main spans, and the girder
depth is 5.0 m.
Address
Xinjun Zhang:1)College of Civil Engineering, Zhejiang University of Technology, Hangzhou, 310023, P.R. China
2)Key Laboratory of Civil Engineering Structures & Disaster Prevention and Mitigation Technology of Zhejiang Province,
Hangzhou, 310023, P.R. China
Binbin Ni:College of Civil Engineering, Zhejiang University of Technology, Hangzhou, 310023, P.R. China
Tianjiao Zhao:College of Civil Engineering, Zhejiang University of Technology, Hangzhou, 310023, P.R. China
Abstract
To quantitative analyze the structural function of transmission lines under wind and provide a research basis for the
wind resistance resilient of them, an assessing framework is established. This framework includes four effects that wind has on
the structural function of transmission lines and is applicable to the state parameters obtained under various wind conditions.
Firstly, for each case, the performance function is established according to its critical parameter and safety factor. Then, the
probabilistic density analysis is conducted on the acquired states parameters of transmission lines. Finally, the index values of
functional state are calculated by the quantitative calculation method proposed based on performance functions and probability
densities. To ensure accuracy in the analysis, plenty of dynamic wind fields should be applied to the investigated lines. The wind
with long-duration can be divided into multiple wind with unit duration, which can improve the computational efficiency when
transmission lines encounter various wind conditions. Based on the state results, weak positions of transmission lines can be
identified. In this paper, a section of one 110 kV transmission line is selected for analysis. From the case study, it is evident that
applying at least 50 random dynamic wind fields to this line is necessary for convergence of the results when the unit duration is
10 minutes and the time interval for obtaining state parameters is 0.1 seconds. Additionally, the span distances should be
reasonably determined based on tower categories and wind-resistant capacity.
Key Words
performance function; probability density; structural functional states; transmission line; weak positions
Address
Cong Yan and Qiang Xie:College of Civil Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
