Effects of ridge height and spacing on the near-surface airflow field and on wind erosion of a sandy soil: Results of a wind tunnel study

Maximizing the benefits of windbreaks requires a thorough understanding of the physical interaction between the wind and the barrier. In this experiment, a profiling set of Pitot tubes was used to measure the airflow field and wind velocity of simulated shrubs in a wind tunnel. The effects of form configurations and row spaces of simulated shrubs on wind-proof effectiveness were in-depth studied. We come to the following results: the weakening intensity of hemisphere-shaped and broom-shaped shrubs on wind velocity was mainly reflected below 2 cm in the root and 6-14 cm in the middle-upper, respectively, while the wind-proof effect of the spindle-shaped shrubs at the canopy (0.2-14 cm height) was the best. Besides, the simulated shrubs under 26.25 cm had the best protection effect on the wind velocity. Moreover, the designed windbreaks with Nitraria tangutorum, more effectively reduced the wind velocity among the windbreak compared to behind the windbreak. In the wind control system, the hemisphere-shaped windbreaks should be applied as near-surface barriers, and the windbreaks of broom-shaped and spindle-shaped can be used as a sheltered forest. The results could offer theoretical guidelines on how to arrange the windbreaks for preventing wind erosion in the most convenient and efficient ways.

Download Full-text

A wind tunnel study of the airflow field and shelter efficiency of mixed windbreaks

Aeolian Research ◽

10.1016/j.aeolia.2019.100544 ◽

2019 ◽

Vol 41 ◽

pp. 100544 ◽

Cited By ~ 2

Author(s):

Rui Ma ◽

Junran Li ◽

Yanjun Ma ◽

Lishan Shan ◽

Xuelin Li ◽

...

Keyword(s):

Wind Tunnel ◽

Airflow Field ◽

Wind Tunnel Study

Download Full-text

Wind tunnel study of multiple factors affecting wind erosion from cropland in agro-pastoral area of Inner Mongolia, China

Journal of Mountain Science ◽

10.1007/s11629-013-2433-y ◽

2013 ◽

Vol 10 (1) ◽

pp. 68-74 ◽

Cited By ~ 7

Author(s):

Ji-jun He ◽

Qiang-guo Cai ◽

Wen-qing Cao

Keyword(s):

Wind Tunnel ◽

Inner Mongolia ◽

Wind Erosion ◽

Factors Affecting ◽

Multiple Factors ◽

Pastoral Area ◽

Wind Tunnel Study

Download Full-text

Windbreak and airflow performance of different synthetic shrub designs based on wind tunnel experiments

PLoS ONE ◽

10.1371/journal.pone.0244213 ◽

2020 ◽

Vol 15 (12) ◽

pp. e0244213

Author(s):

Xia Pan ◽

Zhenyi Wang ◽

Yong Gao ◽

Zhengcai Zhang ◽

Zhongjv Meng ◽

...

Keyword(s):

Wind Speed ◽

Wind Tunnel ◽

Wind Erosion ◽

Protective Effects ◽

Wind Tunnel Experiments ◽

Speed Reduction ◽

Environmental Threats ◽

Wind Speeds ◽

Airflow Field ◽

Reduction Effect

Wind erosion has gained increasing attention as one of the most serious global ecological and environmental threats. Windbreaks are effective at decreasing wind erosion by reducing wind speed to protect crops, livestock, and farmsteads, while providing wildlife habitats. Synthetic shrubs can act as novel windbreaks; however, there is limited knowledge on how their design affects wind speed. This study determined the protective effects (airflow field and sheltering efficiency) based on the design of synthetic shrubs in a wind tunnel. Broom-shaped synthetic shrubs weakened the wind speeds mainly at the middle and upper parts of the shrubs (5–14 cm), while for hemisphere-shaped shrubs this effect was greatest near their bases (below 4 cm) and least in the middle and upper parts (7–14 cm). Spindle-shaped synthetic shrubs provided the best reduction effect in wind range and strength. Moreover, the wind speed reduction ratio decreased with improved wind speeds and ranged from 26.25 cm (between the second and third rows) to 52.5 cm (after the third row). These results provide strong evidence that synthetic shrubs should be considered to decrease wind speed and prevent wind erosion.

Download Full-text

A Wind Tunnel Simulation of Windproof Effectiveness of Simulated Shrubs with Different Spatial Configurations

10.5194/ismc2021-15 ◽

2021 ◽

Author(s):

Xia Pan ◽

Zhenyi Wang ◽

Yong Gao ◽

Xiaohong Dang

Keyword(s):

Wind Tunnel ◽

Wind Velocity ◽

Optimized Design ◽

Near Surface ◽

Wind Tunnel Simulation ◽

Spatial Configurations ◽

Wind Velocities ◽

Airflow Field ◽

Row Space ◽

Better Than

<p>A better understanding of the distribution of the airflow field and wind velocity around the simulated shrubs is essential to provide optimized design and maximize the efficiency of the windbreak forests. In this study, a profiling set of Pitot Tube was used to measure the airflow field and wind velocity of simulated shrubs by wind tunnel simulation. The effects of form configurations and row spaces of simulated shrubs on windproof effectiveness were in-depth studied. We come to the following results: The weakening strength to wind velocities of hemisphere-shaped and broom-shaped shrubs at 26.25 cm was mainly concentrated below 2 cm near the root and 6-14 cm in the middle-upper part, while the spindle-shaped shrubs were at 0.2-14 cm above the canopy, which meant the windproof effect of spindle-shaped shrubs was was better than that of hemisphere-shaped and broom-shaped. With the improvement of row spaces, the weakening height to wind velocities of the hemisphere-shaped shrubs at 35 cm was only concentrated below 2 cm near the root exclude for the 6-14 cm at 26.25 cm, which presented the hemisphere-shaped shrubs were not suitable for the layout of wide row space. Further, the form configurations of simulated shrubs had a stronger influence on wind velocity than row spaces. Moreover, the designed windbreaks with <em>Nitraria tangutorum</em>, which more effectively reduced the wind velocity among the windbreaks compared to behind the windbreaks. In the wind control system, the hemisphere-shaped windbreaks should be applied as near-surface barriers, and the windbreaks of broom-shaped and spindle-shaped can be used as shelterbelts above the near-surface. These analytical findings&#160;offer theoretical guidelines on how to arrange the windbreak forests for preventing wind erosion in the most convenient and efficient ways.</p>

Download Full-text

A wind tunnel study of wind erosion and profile reshaping of transverse sand piles in tandem

Geomorphology ◽

10.1016/j.geomorph.2011.10.024 ◽

2012 ◽

Vol 139-140 ◽

pp. 230-241 ◽

Cited By ~ 13

Author(s):

Almerindo D. Ferreira ◽

Maria Rosário M. Fino

Keyword(s):

Wind Tunnel ◽

Wind Erosion ◽

Wind Tunnel Study ◽

Sand Piles

Download Full-text

MYCORRHIZAL FUNGI PROTECT THE SOIL FROM WIND EROSION: A WIND TUNNEL STUDY

Land Degradation and Development ◽

10.1002/ldr.1136 ◽

2011 ◽

Vol 24 (4) ◽

pp. 385-392 ◽

Cited By ~ 27

Author(s):

K. Burri ◽

C. Gromke ◽

F. Graf

Keyword(s):

Wind Tunnel ◽

Mycorrhizal Fungi ◽

Wind Erosion ◽

Wind Tunnel Study

Download Full-text

A Wind Tunnel Study of the Seasonal Shelter Efficiency of Deciduous Windbreaks

Transactions of the ASABE ◽

10.13031/trans.13782 ◽

2020 ◽

Vol 63 (4) ◽

pp. 913-922

Author(s):

Rui Ma ◽

Junran Li ◽

Yanjun Ma ◽

Linyuan Wei ◽

Yinghua Zhang

Keyword(s):

Wind Speed ◽

Wind Tunnel ◽

Elaeagnus Angustifolia ◽

Russian Olive ◽

Speed Reduction ◽

Airflow Field ◽

Leaf Shedding ◽

Wind Tunnel Study ◽

Deceleration Region ◽

Wind Reduction

HighlightsSeasonal leaf shedding is a key factor affecting the airflow field and shelter efficiency of deciduous windbreaks.The wind deceleration region around modeled Elaeagnus angustifolia L. (Russian olive) windbreaks was larger in winter than in summer, but the intensity of the wind speed reduction was relatively low.The shelter efficiency of E. angustifolia windbreaks in winter was not less than 80% of that in summer.Abstract. The shelter efficiency of windbreaks constructed with deciduous plants changes with their phenological stage. We used Elaeagnus angustifolia L. (Russian olive) as an example and investigated the airflow field and shelter efficiency of deciduous windbreaks with summer facies (with leaves) and winter facies (without leaves) by means of scaled wind tunnel simulation experiments. Our study revealed that different canopy seasonal porosities exert different wind speed reductions inside the windbreaks, which also determine the upwind and downwind wind speed variation. The variation in wind speed was greater in summer than in winter. For the windbreak with summer facies, a large wind acceleration region above and before the windbreak and a strong wind deceleration region inside and after the windbreak were observed. The wind deceleration region around the windbreak with winter facies was larger than that in summer, but the intensity of the wind speed reduction was relatively low. The results of our study further show that although E. angustifolia windbreaks are highly porous in winter, the shelter efficiency was not less than 80% of that in summer. Like any wind tunnel study on windbreaks, producing an artificial plant model that is highly similar to the real field plant is difficult. Nevertheless, our results clearly revealed the wind reduction patterns of deciduous windbreaks due to seasonal porosity caused by leaf shedding, which may provide valuable data for assessing the shelter efficiency of deciduous windbreaks. Keywords: Airflow field, Elaeagnus angustifolia, Seasonal porosity, Wind reduction.

Download Full-text