The Experts below are selected from a list of 192 Experts worldwide ranked by ideXlab platform
Patricia L. Manley - One of the best experts on this subject based on the ideXlab platform.
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Uranium-series tracers of mudwave migration in the Argentine Basin
Deep Sea Research Part II: Topical Studies in Oceanography, 1993Co-Authors: Robert F. Anderson, Martin Q. Fleisher, Patricia L. ManleyAbstract:Abstract Large wave-like sediment structures are formed in the Argentine Basin where active bottom currents carry a heavy load of suspended sediments. A model previously developed to explain the formation and migration of these mudwaves predicts that sediment deposition occurs on the upstream Face of the wave while the Downstream Face experiences reduced deposition, or erosion, depending on the current velocity. Two mudwaves on the Zapiola sediment drift in the Argentine Basin were cored to evaluate the relationship between present-day currents and the migration of these particular structures. 210 Pb and 230 Th were measured in sediments from upstream and Downstream Faces of each mudwave. 210 Pb inventories ranged from 33 to 118 dpm cm −2 among the various locations cored. The general tendency is for higher inventories of 210 Pb to occur on upstream Faces, indicating higher rates of sediment deposition there, as predicted by the model. Over the time scale reflected by the 210 Pb inventories, sediments have accumulated on the Downstream Faces at rates at least one third to one half as high as on the upstream Faces, which rules out complete non-deposition on the Downstream Faces. Unsupported 230 Th activities of upstreamFace sediments are a factor of 3–4 higher than activities of sediments on Downstream Faces, indicating that late Pleistocene sediments are being exposed by erosion on the Downstream Faces. Taken together, these results suggest a situation on the Downstream Face of each mudwave where fresh particulate matter deposited from the water column is being worked into mixed layer sediments under conditions of net sediment erosion.
Robert F. Anderson - One of the best experts on this subject based on the ideXlab platform.
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Uranium-series tracers of mudwave migration in the Argentine Basin
Deep Sea Research Part II: Topical Studies in Oceanography, 1993Co-Authors: Robert F. Anderson, Martin Q. Fleisher, Patricia L. ManleyAbstract:Abstract Large wave-like sediment structures are formed in the Argentine Basin where active bottom currents carry a heavy load of suspended sediments. A model previously developed to explain the formation and migration of these mudwaves predicts that sediment deposition occurs on the upstream Face of the wave while the Downstream Face experiences reduced deposition, or erosion, depending on the current velocity. Two mudwaves on the Zapiola sediment drift in the Argentine Basin were cored to evaluate the relationship between present-day currents and the migration of these particular structures. 210 Pb and 230 Th were measured in sediments from upstream and Downstream Faces of each mudwave. 210 Pb inventories ranged from 33 to 118 dpm cm −2 among the various locations cored. The general tendency is for higher inventories of 210 Pb to occur on upstream Faces, indicating higher rates of sediment deposition there, as predicted by the model. Over the time scale reflected by the 210 Pb inventories, sediments have accumulated on the Downstream Faces at rates at least one third to one half as high as on the upstream Faces, which rules out complete non-deposition on the Downstream Faces. Unsupported 230 Th activities of upstreamFace sediments are a factor of 3–4 higher than activities of sediments on Downstream Faces, indicating that late Pleistocene sediments are being exposed by erosion on the Downstream Faces. Taken together, these results suggest a situation on the Downstream Face of each mudwave where fresh particulate matter deposited from the water column is being worked into mixed layer sediments under conditions of net sediment erosion.
Mustafa M. Aral - One of the best experts on this subject based on the ideXlab platform.
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A Design for Vortex Suppression Downstream of a Submerged Gate
Water, 2020Co-Authors: Ender Demirel, Mustafa M. AralAbstract:Interaction of recirculating and mean flow Downstream of a submerged gate may form significant vortex structures, which may affect the stability of the gate. Although these flow structures that appear in submerged hydraulic jumps received considerable attention in the literature, relatively less work was devoted to the analysis and suppression of the vortex structures Downstream of a submerged gate. In this work, internal flow structure and vortex dynamics around a submerged gate were investigated through laboratory tests and large-eddy simulation (LES) using computational fluid dynamics (CFD). It is shown that numerical results obtained for mean velocity field are in good agreement with the experimental measurements. A helical vortex pair connected with a horseshoe vortex system was identified within the roller region using high-resolution numerical simulations. Damping performance of different types of anti-vortex elements placed on the Downstream Face of the gate are evaluated based on numerical studies. It is shown that the horizontal porous baffle mounted at an elevation below the free surFace reduced the vortex magnitudes in the roller region by 26.8%. With the implementation of the proposed vortex breaker, lift forces acting on the gate lip were reduced by 9.4% and drag forces acting on the Downstream Face of the gate were reduced by 8.6%. Finally, in this study, we assess the performance of the vortex breaker under different flow conditions.
Martin Q. Fleisher - One of the best experts on this subject based on the ideXlab platform.
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Uranium-series tracers of mudwave migration in the Argentine Basin
Deep Sea Research Part II: Topical Studies in Oceanography, 1993Co-Authors: Robert F. Anderson, Martin Q. Fleisher, Patricia L. ManleyAbstract:Abstract Large wave-like sediment structures are formed in the Argentine Basin where active bottom currents carry a heavy load of suspended sediments. A model previously developed to explain the formation and migration of these mudwaves predicts that sediment deposition occurs on the upstream Face of the wave while the Downstream Face experiences reduced deposition, or erosion, depending on the current velocity. Two mudwaves on the Zapiola sediment drift in the Argentine Basin were cored to evaluate the relationship between present-day currents and the migration of these particular structures. 210 Pb and 230 Th were measured in sediments from upstream and Downstream Faces of each mudwave. 210 Pb inventories ranged from 33 to 118 dpm cm −2 among the various locations cored. The general tendency is for higher inventories of 210 Pb to occur on upstream Faces, indicating higher rates of sediment deposition there, as predicted by the model. Over the time scale reflected by the 210 Pb inventories, sediments have accumulated on the Downstream Faces at rates at least one third to one half as high as on the upstream Faces, which rules out complete non-deposition on the Downstream Faces. Unsupported 230 Th activities of upstreamFace sediments are a factor of 3–4 higher than activities of sediments on Downstream Faces, indicating that late Pleistocene sediments are being exposed by erosion on the Downstream Faces. Taken together, these results suggest a situation on the Downstream Face of each mudwave where fresh particulate matter deposited from the water column is being worked into mixed layer sediments under conditions of net sediment erosion.
Jian Yang - One of the best experts on this subject based on the ideXlab platform.
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Practical procedure for predicting non-uniform temperature on the exposed Face of arch dams
Applied Thermal Engineering, 2010Co-Authors: Feng Jin, Zheng Chen, Jin-ting Wang, Jian YangAbstract:Temperature distribution on the exposed Face (especially the Downstream Face) of arch dams is non-uniform, to a certain extent, due to the variation in solar radiation striking the surFace. However, the temperature at the same elevation across the dam axis is generally assumed to be uniform in the design specifications for arch dams because there is no accepted procedure for defining the non-uniform temperature field. In this paper, a practical model for predicting the non-uniform temperature of the exposed Face is presented by considering both solar radiation and shading effects. The ASHRAE clear sky model was adopted to calculate the solar radiation, and a ray-tracing algorithm was used to analyze the shade of surrounding terrain and the structure per se. The real-life case study presented in this study shows that the proposed model was effective in simulating and accessing reasonable thermal distribution. Subsequently, the case study also reveals that the non-uniform temperature had a significant effect on surFace thermal stress and crack propagation.