Study on Soil Erosion by Wind Tunnel Experiment of Semi-Arid Steppe in Inner Mongolia

2012 ◽  
Vol 518-523 ◽  
pp. 4766-4770
Author(s):  
Lan Gao ◽  
Yu Jun Qiu ◽  
Xue Yong Zou ◽  
Ren De Wang ◽  
Na Zhou
Keyword(s):  
Particle Size ◽  
Wind Speed ◽  
Wind Tunnel ◽  
Soil Erosion ◽  
Moisture Content ◽  
Inner Mongolia ◽  
Erosion Rate ◽  
Wind Erosion ◽  
Sand Transport ◽  
Average Particle

The characteristics of soil erosion of steppe in Inner Mongolia were studied in wind-tunnel tests. The results indicated that the soil in this region consists primarily of sand and coarse silt, with particle sizes mainly between 0.02 and 1mm, and it is defined as erodible sandy soil. The eroded sediments are mainly concentrated at heights of 0~24cm, and the extreme value of particle size is clearly in the range 100~300μm. Average particle size increased with increasing wind speed, and it decreased exponentially in the vertical direction, reflecting the characteristics of sand transport by wind. The relationship between wind erosion rate and wind speed assumes a power function with correlation coefficients greater than 0.9. A wind speed of 15m/s is a significance point above which wind erosion in this region becomes very large. Soil erosion rate decreases logarithmically as soil moisture content and vegetation coverage increase, and the 5% level of moisture content is a turning point.

Determination of grinding parameters of fenugreek seed

1970 ◽  
Vol 26 (1) ◽  
pp. 16 ◽  
Author(s):  
S Balasubramanian ◽  
Rajkumar Rajkumar ◽  
K K Singh
Keyword(s):  
Particle Size ◽  
Energy Consumption ◽  
Moisture Content ◽  
Specific Energy ◽  
Feed Rate ◽  
Average Particle Size ◽  
Specific Energy Consumption ◽  
Average Particle ◽  
Fenugreek Seeds ◽  
Fenugreek Seed

Experiment to identify ambient grinding conditions and energy consumed was conducted for fenugreek. Fenugreek seeds at three moisture content (5.1%, 11.5% and 17.3%, d.b.) were ground using a micro pulverizer hammer mill with different grinding screen openings (0.5, 1.0 and 1.5 mm) and feed rate (8, 16 and 24 kg h-1) at 3000 rpm. Physical properties of fenugreek seeds were also determined. Specific energy consumptions were found to decrease from 204.67 to 23.09 kJ kg-1 for increasing levels of feed rate and grinder screen openings. On the other hand specific energy consumption increased with increasing moisture content. The highest specific energy consumption was recorded for 17.3% moisture content and 8 kg h-1 feed rate with 0.5 mm screen opening. Average particle size decreased from 1.06 to 0.39 mm with increase of moisture content and grinder screen opening. It has been observed that the average particle size was minimum at 0.5 mm screen opening and 8 kg h-1 feed rate at lower moisture content. Bond’s work index and Kick’s constant were found to increase from 8.97 to 950.92 kWh kg-1 and 0.932 to 78.851 kWh kg-1 with the increase of moisture content, feed rate and grinder screen opening, respectively. Size reduction ratio and grinding effectiveness of fenugreek seed were found to decrease from 4.11 to 1.61 and 0.0118 to 0.0018 with the increase of moisture content, feed rate and grinder screen opening, respectively. The loose and compact bulk densities varied from 219.2 to 719.4 kg m-3 and 137.3 to 736.2 kg m-3, respectively.  

scholarly journals Wheat Grinding Process with Low Moisture Content: A New Approach for Wholemeal Flour Production

Processes ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 32
Author(s):  
Waleed H. Hassoon ◽  
Dariusz Dziki ◽  
Antoni Miś ◽  
Beata Biernacka
Keyword(s):  
Particle Size ◽  
Moisture Content ◽  
Average Particle Size ◽  
Average Particle ◽  
Grinding Process ◽  
Mixing Properties ◽  
New Approach ◽  
Grain Moisture ◽  
Flour Production ◽  
And Storage

The objective of this study was to determine the grinding characteristics of wheat with a low moisture content. Two kinds of wheat—soft spelt wheat and hard Khorasan wheat—were dried at 45 °C to reduce the moisture content from 12% to 5% (wet basis). Air drying at 45 °C and storage in a climatic chamber (45 °C, 10% relative humidity) were the methods used for grain dehydration. The grinding process was carried out using a knife mill. After grinding, the particle size distribution, average particle size and grinding energy indices were determined. In addition, the dough mixing properties of wholemeal flour dough were studied using a farinograph. It was observed that decreasing the moisture content in wheat grains from 12% to 5% made the grinding process more effective. As a result, the average particle size of the ground material was decreased. This effect was found in both soft and hard wheat. Importantly, lowering the grain moisture led to about a twofold decrease in the required grinding energy. Moreover, the flour obtained from the dried grains showed higher water absorption and higher dough stability during mixing. However, the method of grain dehydration had little or no effect on the results of the grinding process or dough properties.

scholarly journals Populus simonii Carr. Reduces Wind Erosion and Improves Soil Properties in Northern China

Forests ◽  
2019 ◽  
Vol 10 (4) ◽  
pp. 315 ◽  
Author(s):  
Jieming Zhang ◽  
Guodong Jia ◽  
Ziqiang Liu ◽  
Dandan Wang ◽  
Xinxiao Yu
Keyword(s):  
Sediment Transport ◽  
Wind Speed ◽  
Wind Erosion ◽  
Surface Wind ◽  
Chemical Properties ◽  
Stand Density ◽  
Northern China ◽  
Stand Age ◽  
Sand Transport ◽  
Total N

To assess the ecological effects of poplar stands with different densities and ages, fixed observation sites were established in selected standard forest plots. Daily dynamics of wind speed and sand transport rate were monitored over an erosive period (March to June) in 2017. Soil characteristics were also measured at these plots. Average daily wind speed and average daily wind erosion modulus decreased significantly after the establishment of poplar trees on sandy land, while soil density decreased significantly, soil hardness increased greatly, and soil organic carbon, total N, and available P levels increased significantly. With increasing stand density, average daily wind speed and daily sediment transport firstly decreased and then increased, while the investigated soil nutrients showed the opposite trend. A tree density of 1320–1368 trees·hm−2 significantly reduced surface wind erosion. With the increase in forest age, the average daily wind speed and daily sediment transport declined, while soil physical and chemical properties were gradually improved. At a stand age of 40 years, wind-caused soil erosion significantly reduced. Taking these effects into consideration, the design and management of protective forest systems in arid and semi-arid areas can be greatly improved.

scholarly journals Wind tunnel investigation on the dust emission characteristics of high moisture coal piles

2020 ◽  
Vol 145 ◽  
pp. 02019
Author(s):  
Ningning Hong ◽  
Shitao Peng ◽  
Hongxin Zhao ◽  
Ning Su
Keyword(s):  
Wind Speed ◽  
Wind Tunnel ◽  
Moisture Content ◽  
Coal Dust ◽  
Dust Emission ◽  
Wind Tunnel Test ◽  
High Moisture Content ◽  
High Moisture ◽  
Emission Behavior ◽  
The Relationship

With the increasing requirements of environmental protection, a large number of new wet dust suppression technologies are used in the port in recent years, such as watering at the bottom of the Dumper Shed, etc. So the moisture content of coal is more than 10% often appear. Relevant studies show that the amount of dust from coal (conventional moisture content) pile is directly proportional to the high power of wind speed. But studies on high moisture content coal are rare. In this study, Wind tunnel test was carried out to study the dust emission behavior of coal with high moisture content (13.7% and 14.3%). The results show that the relationship between coal dust and wind speed tends to be linear under high moisture content. The study can provide a basis research for the estimation of coal dust emission in port.

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

PLoS ONE ◽  
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.

Grinding Characteristics of Black Soybeans (Glycine max) at Varied Moisture Contents: Particle Size, Energy Consumption, and Grinding Kinetics

2014 ◽  
Vol 10 (3) ◽  
pp. 347-356 ◽  
Author(s):  
Youn Ju Lee ◽  
Jin Sil Yoo ◽  
Won Byong Yoon
Keyword(s):  
Particle Size ◽  
Energy Consumption ◽  
Moisture Content ◽  
Strong Dependence ◽  
Average Particle Size ◽  
Average Particle ◽  
Black Soybean ◽  
Moisture Contents ◽  
Soybean Powder ◽  
Grinding Kinetics

Abstract The effects of moisture content on the grinding characteristics of black soybeans were studied. The average particle size of the black soybean powder was smaller as the moisture content was decreased by drying. Bond’s constants and the work index showed lower values as the moisture content decreased. A sigmoid model accurately described the grinding kinetics of the black soybean powder (R2 > 0.90). The parameters in the sigmoidal models were useful to explain the effect of moisture content during grinding. However, at higher moisture contents, the sigmoid model did not accurately fit the grinding kinetics. The grinding characteristics of black soybeans showed a strong dependence on moisture content. Adjusting the moisture contents of black soybeans using a pretreatment such as drying is very important to control the grinding characteristics, including the energy consumption and the average particle size, during grinding.

scholarly journals Exploring soil particle size fraction and spatial redistribution of 137Cs in sloping landscapes with different lynchet height of terracing hedgerows in the remote mountain region, southwestern China

2021 ◽  
Author(s):  
Ping Zhou ◽  
Wenhua Zhuang ◽  
Zhonglin Shi
Keyword(s):  
Particle Size ◽  
Soil Erosion ◽  
Soil Conservation ◽  
Erosion Rate ◽  
Soil Depth ◽  
Mountain Region ◽  
Conservation Strategy ◽  
Slope Position ◽  
K Value ◽  
Sloping Lands

Abstract Soil erosion is a global environmental problem related to anthropogenic activities, as well as being influenced by natural factors. The sloping cultivated lands, which have serious soil erosion, constitute a major proportion of landscape in the remote mountain region. The traditional soil conservation strategy, referred as certain height of lynchets on the edge of the terracing hedgerows of the sloping lands, plays an effective part in soil and water conservation. A typical sloping landscape with lynchet of terracing hedgerows was chosen in this study. The results showed that fine-grained sediment was deposited in front of the lynchet of terracing hedgerows, especially particle size grouped at < 0.002mm and 0.002-0.02mm. The profiles 137Cs concentration of the lynchet from the upper to the lower sloping landscape showed first increased then decreased trends as the soil depth increased. 137Cs inventory generally increased along the whole sloping landscapes. And the results suggested that the mean 137Cs inventory and erosion rate could be represented by the average value of the middle slope position. The highest value of annual erosion modulus reached to 4917.06 tkm− 2a− 1 on the upper site of the sloping lands. While the annual erosion modulus were synchronous reduced from the upper to the lower of the slope landscape, the erosion rate had the similar trends. Meanwhile, K values of soil erodibility changed from 0.0338 thm2h (hm− 2MJ− 1mm− 1) to 0.0375 thm2h (hm− 2MJ− 1mm− 1) along the slope length. There existed the logarithmic relationship between K value and 137Cs inventory in the correspondent slope position. Therefore, it is useful to study spatial patterns of soil erosion in different slope positions with the different height of lynchet of terracing hedgerows of the whole sloping landscape. Also it is important for implementing soil conservation strategy in the remote mountain region, China.

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