در هنگام جستجو کلمه در قسمت عنوان میتوانید کلمات مورد جستجو را با کاراکتر (-) جدا کنید.
کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: علوم و مهندسی آبیاری
- نوع مقاله: Journal Article
- کلمات کلیدی: Dust,Erosion,Soil moisture content,Wind Tunnel,Soil Stabilization,Granulation
- چکیده: This research conducted various experiments using a wind tunnel on soil samples from the most critical parts of dust sources in southeastern of Ahvaz. The main goal of this study is to show the effect of moisture on the movement of soil particles in the dust centers. The laboratory work was carried out in two parts: a: Addition of water to completely disturbed soil surface (wetting in the bag) b: Addition of water to soil layers of samples wetting that was named pseudo undisturbed soil.
The results showed that dust generation under natural conditions (dry soils) in a laboratory wind tunnel will be 53 times more than the pseudo undisturbed soils with moisture content of 2-4% in volume. Moreover, soils with moisture contents of 5-8 and 10-12% do not differ significantly from those with 2-4% moisture content in preventing dust generation. If soil surface is disturbed after it is provided with adequate moisture, not only will dust generation not decrease compared to the case when the soil surface was dry but it will also increase by 25 percent. The practical point of this study is that in the study area, increasing soil moisture between 2 to 4% can greatly reduce the formation of dust.- چکیده انگلیسی: This research conducted various experiments using a wind tunnel on soil samples from the most critical parts of dust sources in southeastern of Ahvaz. The main goal of this study is to show the effect of moisture on the movement of soil particles in the dust centers. The laboratory work was carried out in two parts: a: Addition of water to completely disturbed soil surface (wetting in the bag) b: Addition of water to soil layers of samples wetting that was named pseudo undisturbed soil.
The results showed that dust generation under natural conditions (dry soils) in a laboratory wind tunnel will be 53 times more than the pseudo undisturbed soils with moisture content of 2-4% in volume. Moreover, soils with moisture contents of 5-8 and 10-12% do not differ significantly from those with 2-4% moisture content in preventing dust generation. If soil surface is disturbed after it is provided with adequate moisture, not only will dust generation not decrease compared to the case when the soil surface was dry but it will also increase by 25 percent. The practical point of this study is that in the study area, increasing soil moisture between 2 to 4% can greatly reduce the formation of dust.- انتشار مقاله: 20-10-1399
- نویسندگان: Abdolazim Ghomeishi,Mehdi Ghomeshi,Mohammad Mahmoudian Shoushtari,Ahmad Landi,Mohammad Hosain Purmohammadi
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Advanced Biological and Biomedical Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Turbidity Currents,Mobile Bed,Flow Profiles,Bend
- چکیده:
- چکیده انگلیسی: Turbidity currents in the ocean and lakes are driven by suspended sediment. The vertical profiles of velocity and excess density are shaped by interaction between the current and bed as well as between the current and the ambient water. This paper presents 48 series of experiments in which saline gravity currents flow through a laboratory sinuous flume. flume contains three successive bends with three different relative curvature radiuses: R/B=2, 4 and 6, 8.5m length, 20cm width and 70cm height. Experiments performed by four discharges (0.7, 1, 1.5, 2 lit/s) and four concentrations (10, 15, 20, 25 gr/lit). ADV was used to record the local velocity. According to the results of experiments on the mobile bed, increasing the concentration of the incoming flow, the flow velocity of the fluid is also increased and, the maximum velocity occurs near the bed instead of the top of the current. The important point in the flow rate profiles is that the rate of increase in velocity depends on changes in the form of the bed due to the increase in concentration. By increasing concentrations of turbidity flow, the shear stress of the bed is also increased. Therefore, the rate of increase in velocity will occur by removing the bed forms and reducing the roughness and shear stress of the bed. Thus, increasing the concentration increases the power of the current, so at the beginning, the roughness and shear stress of the bed increased and then by removal of bed forms shear stress decreased.
- انتشار مقاله: 21-01-1398
- نویسندگان: Marzieh Mohammadi,Mehdi Ghomeshi
- مشاهده