Comparison of wind characteristics in different directions of deep-cut gorges based on field measurements

et al. 2021

Applied Sciences

Windblown sand two-phase flow characteristics become an essential factor in evaluating the windblown sand load on infrastructures and civil structures. Based on the measured wind characteristics in arid desert regions, windblown sand flow fields with three kinds of sand beds are simulated in the wind tunnel, respectively. The results indicate that the characteristic saltation height of sand particles increases with the wind speed and particle size in the windblown sand flow field. As the sand concentration increases, the wind speed decreases, and the turbulence intensity increases. The concentration, energy, and impact pressure of sand particles increase with increasing wind speed and decrease exponentially with increasing height. At the same wind speed, the concentration, energy, and impact pressure of the coarse sand, fine sand, and mixed sand increases, in turn. Moreover, the variation of kinetic energy with height is similar to that of total energy with height and the proportion of potential energy to total energy is quite small.

Section: Introductionmentioning

confidence: 99%

Wind Tunnel Test on Windblown Sand Two-Phase Flow Characteristics in Arid Desert Regions

Huang

et al. 2021

Applied Sciences

“…Wang et al, 2020). The main performance is that the mainstream wind direction is consistent with the gorge direction, and the wind parameters corresponding to different wind directions are different (Zhang et al, 2021). At the same time, the influence of thermal and local shielding effects on wind characteristics in mountainous areas is also found and proved (Zhang et al, 2019), which reveals the causes of strong daily wind, and greatly promotes the understanding of wind fields in mountainous areas.…”

Section: Introductionmentioning

confidence: 96%

“…Three different types of land surfaces were described by this method, and this lays a good foundation for the study of the wind field in the mountain gorge area. Thus, many researchers have measured different mountainous terrain, including U-shaped gorge (F. , V-shaped gorge (Zhang et al, 2021), Y-shaped river channel (Huang et al, 2019), and others. The results show that the wind field in mountainous areas is greatly constrained by local terrain, which is different from that in open flat areas (Hui et al, 2009;Li et al, 2017;D.…”

Section: Introductionmentioning

confidence: 99%

Combined wind profile characteristics based on wind parameters joint probability model in a mountainous gorge

Jiang

et al. 2022

Nat Hazards

Self Cite

Long-span bridges in mountainous areas are greatly disturbed by wind, and the wind field in the mountain gorge bridge site is extremely complex. Therefore, it is of great engineering significance to accurately evaluate the wind field characteristics of this kind of terrain. In this paper, to enhance understanding of this kind of wind field, the wind field in a mountainous gorge is measured for a long time using wind radar, and the mean wind parameters is statistically analyzed.The results show that the mean wind parameters vary greatly under different wind directions, and the wind speed profile does not meet the power-law model. Therefore, a mixed model suitable for the wind speed profile in a mountainous gorge is proposed. Additionally, GEV distribution and Logistic distribution are found to be suitable for describing the distribution characteristics of wind speed and angle of attack, respectively. In addition, considering the correlation between wind parameters, this paper also constructs the joint probability model of wind speed and angle of attack at different heights by the Copula function. Thus, a combined wind parameters profile model is developed under different exceedance probabilities based on the inverse first-order reliability method (IFORM). This study can provide a reference for the construction of the joint probability model of wind parameters.

“…There is a lot of research on the flow field characteristics that affect the wind effect of structures, including the flow field characteristics of monsoon [13], typhoon [14], and tornado [15]. At the same time, some researchers have studied the characteristics of the flow field around the structures by changing the structural shape and installing appurtenances on the surface of structures, and have achieved some results [16,17].…”

Section: Introductionmentioning

confidence: 99%

Study on Flow Field Characteristics in Sandstorm Conditions Using Wind Tunnel Test

Huang

et al. 2022

Atmosphere

To study the sandstorm resistance design of civil structures and transportation infrastructures, the sandstorm flow fields with various grain concentrations were simulated by the windblown sand tunnel. The results show that the grain concentration profile presents an exponential decay form before the critical wind speed; as the test speed increases, the grain concentration decreases initially and increases afterwards with height, and the characteristic height of moving grain increases while the creep percentage decreases. Moving sand grains reduce wind speed and increase turbulence intensity, and the whole process is affected by grain concentration. The moving grain and the turbulence of the sandstorm flow field form a mutual feedback mechanism, which affects the wind-induced response and impact response to structures. The variation of kinetic energy with height is similar to that of total energy with height in the sandstorm flow fields. Specifically, the grain energy increases with increasing concentration and wind speed, but decreases initially and increases afterwards with height. Furthermore, the critical heights of the grain energy and concentration profile are both about 0.2 m, which has little impact on structures.