Simulating Efficiency of Resistance to Wind Erosion in Area of Complex Erosion by Wind and Water

Used the method of transplanting in studying area, simulated different arrangement of plant spacing and observed the wind speed by using HTSW-18 multiple-sensor automatic anemoscope. The results showed that two kinds of plants of different plant spacing can effectively reduce wind speed, the ration of reducing wind velocity of shelterbelts were biggest at the observation point of 1H behind the shelterbelt. The ration of reducing wind velocity and roughness of shelterbelt of Salix psammophila was better than that of Artemisia ordosica Krasch. under the same plant spacing. The increasing of Artemisia ordosica Krasch. was seventeen times higher than that of control at the observation point of 1H. The roughness of Salix psammophila at the observation point of 1H was twenty-five times higher than control, and that of Artemisia ordosica Krasch. was seventeen times higher than control.

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THE EFFECT OF DARRIEUS AND SAVONIUS WIND TURBINES POSITION ON THE PERFORMANCE OF THE HYBRID WIND TURBINE AT LOW WIND SPEED

10.31224/osf.io/grbmv ◽

2020 ◽

Author(s):

Nawfal M. Ali ◽

Abdul Hassan A. K ◽

Sattar Aljabair

Keyword(s):

Wind Speed ◽

Wind Turbine ◽

Wind Velocity ◽

Vertical Axis ◽

Aerodynamic Characteristics ◽

The Other ◽

Vertical Axis Wind Turbine ◽

Low Wind Speed ◽

Turbine Model ◽

Better Than

This paper presents an experimental and numerical simulation to investigate a hybrid vertical axis wind turbine model highly efficient which can be worked at low wind speed by studying the aerodynamic characteristics of four models of hybrid VAWTs. The hybrid WT consists of the SWT having two blades and the DWT type straight having two blades. Four models were constructed to study experimentally and numerically to choose the best model. Two models were DWT in the upper and SWT in the lower, also two models were SWT in the upper and DWT in the lower. The phase stage angle between the turbines is 0o and 90o . The experimental and numerical results showed that the performance of hybrid WT where DWT in the upper and SWT in the lower with phase stage 90o is better than in the other models, it can be started to work at a wind velocity of 2.2 m/s. At the wind velocity 3 m/s, the values of the parameters are the rotational speed (198 rpm), the CP (0.3195), the CT (0.2003), the TSR (1.6) and self-starting rotation at this value of wind velocity (3 m/s). The efficiency of extracting the wind power by hybrid WT is (51.2 %).

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Wind speed in spring dominated the decrease in wind erosion across the Horqin Sandy Land in northern China

Ecological Indicators ◽

10.1016/j.ecolind.2021.107599 ◽

2021 ◽

Vol 127 ◽

pp. 107599

Author(s):

Hanbing Zhang ◽

Jian Peng ◽

Chaonan Zhao ◽

Zihan Xu ◽

Jianquan Dong ◽

...

Keyword(s):

Wind Speed ◽

Wind Erosion ◽

Northern China ◽

Horqin Sandy Land ◽

Sandy Land

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Analysis for the Effect of Wind Barrier on Reducing Wind Velocity across a Bridge

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.256-259.2739 ◽

2012 ◽

Vol 256-259 ◽

pp. 2739-2742

Author(s):

Ji Hong Bi ◽

Peng Lu ◽

Jian Wang ◽

Chun Bao

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Wind Speed ◽

Wind Velocity ◽

Efficient Design ◽

Wind Barrier ◽

Strong Winds

A bridge, which is located in the route of typhoon, is considered how to assure normal traffic use against strong winds. As one of the measures, wind barrier is proposed to be set on both sides of the bridge section for reducing wind velocity across it. In this study, an analysis by using CFX, a computational fluid dynamics program, is carried out to investigate the effects of wind barrier. The speed of wind is assumed as 60m/s. To find out an efficient design of the boards, different porosity ratios(r) of the boards is assumed for comparison. The result shows that wind barrier could reduce the wind speed across the bridge effectively.

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Experimental Study of Vertical Axis Wind Turbine with Wind Speed Self-Adapting

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.215-216.1323 ◽

2012 ◽

Vol 215-216 ◽

pp. 1323-1326

Author(s):

Ming Wei Xu ◽

Jian Jun Qu ◽

Han Zhang

Keyword(s):

Wind Speed ◽

Wind Turbine ◽

Wind Velocity ◽

Vertical Axis ◽

Maximum Power ◽

The Self ◽

Power Coefficient ◽

Speed Ratio ◽

Vertical Axis Wind Turbine ◽

Opening And Closing

A small vertical axis wind turbine with wind speed self-adapting was designed. The diameter and height of the turbine were both 0.7m. It featured that the blades were composed of movable and fixed blades, and the opening and closing of the movable blades realized the wind speed self-adapting. Aerodynamic performance of this new kind turbine was tested in a simple wind tunnel. Then the self-starting and power coefficient of the turbine were studied. The turbine with load could reliably self-start and operate stably even when the wind velocity was only 3.6 m/s. When the wind velocity was 8 m/s and the load torque was 0.1Nm, the movable blades no longer opened and the wind turbine realized the conversion from drag mode to lift mode. With the increase of wind speed, the maximum power coefficient of the turbine also improves gradually. Under 8 m/s wind speed, the maximum power coefficient of the turbine reaches to 12.26%. The experimental results showed that the new turbine not only improved the self-starting ability of the lift-style turbine, but also had a higher power coefficient in low tip speed ratio.

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Wind Velocity Decreasing Effects of Windbreak Fence for Snowfall Measurement

Advances in Meteorology ◽

10.1155/2014/791256 ◽

2014 ◽

Vol 2014 ◽

pp. 1-20

Author(s):

Ki-Pyo You ◽

Young-Moon Kim

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Wind Velocity ◽

Wind Tunnel Test ◽

Field Measurements ◽

Wind Flow ◽

Dynamics Analysis ◽

Computational Fluid Dynamics Analysis ◽

Better Than ◽

Velocity Decrease

Meteorological observatories use measuring boards on even ground in open areas to measure the amount of snowfall. In order to measure the amount of snowfall, areas unaffected by wind should be found. This study tried to determine the internal wind flow inside a windbreak fence, identifying an area unaffected by wind in order to measure the snowfall. We performed a computational fluid dynamics analysis and wind tunnel test, conducted field measurements of the type and height of the windbreak fence, and analyzed the wind flow inside the fence. The results showed that a double windbreak fence was better than a single windbreak fence for decreasing wind velocity. The double fence (width 4 m, height 60 cm, and fixed on the bottom) has the greatest wind velocity decrease rate at the central part of octagonal windbreak.

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Poplar efficiency in shelterbelts at some localities in Vojvodina

Glasnik Sumarskog fakulteta ◽

10.2298/gsf0693121l ◽

2006 ◽

pp. 121-128

Author(s):

Sara Lukic ◽

Stevan Dozic

Keyword(s):

Wind Velocity ◽

Standard Method ◽

Agricultural Production ◽

Wind Erosion

The effect of poplar shelterbelts on the change of wind velocity has been studied. The measurements were performed by standard method at several points in front of the belt, behind and within the belt. Based on the study values, it can be concluded that poplar is efficient in reducing wind velocity, as the species for shelterbelts which are established for wind breaking. Their effect is significant at the distances up to 100 m behind the belt, which is significant when networks of shelterbelts are established to control wind erosion in the large deforested lowland areas which are mainly used for agricultural production. .

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Potential threat of southern Moravia soils by wind erosion

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun200452020033 ◽

2004 ◽

Vol 52 (2) ◽

pp. 33-42 ◽

Cited By ~ 1

Author(s):

Jana Dufková

Keyword(s):

Wind Velocity ◽

Wind Erosion ◽

Linear Trend ◽

Soil Surface ◽

Potential Threat ◽

Soil Humidity ◽

Average Wind ◽

Humidity Index ◽

Southern Moravia ◽

Average Wind Velocity

Wind erosion is caused by meteorological factors such as wind, precipitation and evaporation that influence the soil humidity. Erosive-climatological factor expresses wind and humidity conditions of particular landscape. This is an index of the influence of average soil surface humidity and average wind velocity on average soil erodibility by wind. On the basis of average wind velocity and Konček’s humidity index, the values of the erosive-climatological factor for three chosen areas of Czech republic (Telč-Kostelní Myslová, Znojmo-Kuchařovice and Brno-Tuřany), where the pro-cesses of wind erosion could exist, were evaluated. Thus, the change of the factor’s value during the period of 1961 – 2000 was studied. The linear trend for the region of Brno and Znojmo (dry areas) shows increasing threat of soils by wind erosion, the contrary situation is at the humid area (Telč). The results prove the influence of soil humidity on the erosive-climatological factor and hereby the influence on wind erosion spreadout.

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Wind Profiling by Passive Optical Method

EPJ Web of Conferences ◽

10.1051/epjconf/202023706021 ◽

2020 ◽

Vol 237 ◽

pp. 06021

Author(s):

Vadim Dudorov ◽

Anna Eremina

Keyword(s):

Wind Speed ◽

Wind Velocity ◽

Optical Method ◽

Video Sequence ◽

Distant Object ◽

Observation Path

Possibilities of the wind speed profiling along an observation path of a distant object from the analysis of a video sequence of images of the object are studied in this work. The method is based on the analysis of two neighbor frames of a video sequence of incoherent images. The wind velocity retrieved is compared with data of acoustic anemometers.

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Interactive Effects of Moss-Dominated Crusts andArtemisia ordosicaon Wind Erosion and Soil Moisture in Mu Us Sandland, China

The Scientific World JOURNAL ◽

10.1155/2014/649816 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Yongsheng Yang ◽

Chongfeng Bu ◽

Xingmin Mu ◽

Hongbo Shao ◽

Kankan Zhang

Keyword(s):

Soil Moisture ◽

Wind Erosion ◽

Water Environment ◽

Interactive Effects ◽

Vegetative Cover ◽

Artemisia Ordosica ◽

Negative Effects ◽

Rainwater Infiltration ◽

Bare Sand ◽

Soil Crusts

To better understand the effects of biological soil crusts (BSCs) on soil moisture and wind erosion and study the necessity and feasibility of disturbance of BSCs in the Mu Us sandland, the effects of four treatments, including moss-dominated crusts alone,Artemisia ordosicaalone, bare sand, andArtemisia ordosicacombined with moss-dominated crusts, on rainwater infiltration, soil moisture, and annual wind erosion were observed. The major results are as follows. (1) The development of moss-dominated crusts exacerbated soil moisture consumption and had negative effects on soil moisture in the Mu Us sandland. (2) Moss-dominated crusts significantly increased soil resistance to wind erosion, and when combined withArtemisia ordosica, this effect became more significant. The contribution of moss-dominated crusts underArtemisia ordosicawas significantly lower than that of moss-dominated crusts alone in sites where vegetative coverage > 50%. (3) Finally, an appropriate disturbance of moss-dominated crusts in the rainy season in sites with high vegetative coverage improved soil water environment and vegetation succession, but disturbance in sites with little or no vegetative cover should be prohibited to avoid the exacerbation of wind erosion.

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Growth Characteristics of Summer Cover Crop Grasses and their Relation to Soil Aggregate Stability and Wind Erosion Control in Arid Southwest

Applied Engineering in Agriculture ◽

10.13031/aea.13972 ◽

2021 ◽

Vol 37 (1) ◽

pp. 11-23

Author(s):

Murali K. Darapuneni ◽

Omololu J. Idowu ◽

Bilgi Sarihan ◽

David DuBois ◽

Kulbhushan Grover ◽

...

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Wind Erosion ◽

Aggregate Stability ◽

Erosion Control ◽

Soil Aggregate Stability ◽

Irrigation Regimes ◽

Arid Southwest ◽

Wind Erosion Control ◽

Better Than

HighlightsFour summer cover crops under two irrigation regimes were tested for soil wind erosion control.Soil aggregate stability and wind erosion losses were improved with plant cover in the peak summer.Sorghum sudan is a prominent summer species for wind erosion control in the arid southwest. Abstract. Cover crops can have significant impacts on minimizing soil erosion by wind, which is a common problem in the arid southwest. A study was conducted at NMSU Leyendecker Plant Science Center, Las Cruces, New Mexico, to evaluate the impacts of selected summer cover crops on soil loss during wind erosion events. Four summer grass species [Japanese millet (Echinochloa esculenta), pearl millet (Pennisetum glaucum), brown top millet (Urochloa ramosa (L.) Nguyen), and sorghum sudangrass (Sorghum bicolor × S. bicolor var. Sudanese)] were randomly assigned to four blocks under two irrigation regimes (full-irrigation and deficit-irrigation). Results showed significant effect of grasses on horizontal soil flux compared to control under both irrigation regimes. When comparing the grasses, sorghum sudan grass performed better than the other tested summer cover crops for soil surface protection from wind erosion with its higher ground coverage, higher plant density, taller plant height and higher amount of biomass, while brown top millet was least effective in terms of plant and erosion control characteristics (P=0.05). Pearl millet and Japanese millet performed better than brown top millet, but was as effective as sorghum sudan as barriers against the wind erosion. Therefore, sorghum sudan is a prominent cover crop for summer in the arid zones of desert southwest. Producers of this region can be significantly benefited from the current research recommendations about cover crops choices for summer season. Keywords: Arid climates, Cover cropping, Summer grasses, Wind erosion control.

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