The Experts below are selected from a list of 12282 Experts worldwide ranked by ideXlab platform
Ahmed Raad Aladhadh - One of the best experts on this subject based on the ideXlab platform.
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influence of relative density on static soil structure Frictional Resistance of dry and saturated sand
Geotechnical and Geological Engineering, 2014Co-Authors: Binod Tiwari, Ahmed Raad AladhadhAbstract:Soil–structure Frictional Resistance is required while designing foundation systems and retaining walls. Although much more attention has been paid in recent years regarding soil–structure interaction for dynamic loading, highly conservative values of the static Frictional Resistance between soil and structure are used in design. Not much emphasis has been given lately to evaluate static Frictional Resistance between soil and structure. In this study, a well graded sand, as per USCS classification system, was prepared in the laboratory at different relative densities and moisture contents i.e. dry and saturated, and Frictional Resistances of those soils were measured. Those soil samples were also sheared against wood, concrete, and steel blocks and corresponding soil–structure Frictional Resistances were measured. Moreover, similar experiments were performed for saturated and loose poorly graded sand (SP), silty sand (SM) and poorly graded sand with silt (SP–SM). The study result shows that the difference between Frictional Resistance of soil and skin friction depends on the type of soil, relative density and the moisture content. Interestingly, shear envelopes for soil–soil and soil–structure shearing Resistance exhibited curvature. The traditionally adopted soil–structure Frictional Resistance values adopted by various geotechnical manuals were found to be highly conservative.
Binod Tiwari - One of the best experts on this subject based on the ideXlab platform.
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influence of relative density on static soil structure Frictional Resistance of dry and saturated sand
Geotechnical and Geological Engineering, 2014Co-Authors: Binod Tiwari, Ahmed Raad AladhadhAbstract:Soil–structure Frictional Resistance is required while designing foundation systems and retaining walls. Although much more attention has been paid in recent years regarding soil–structure interaction for dynamic loading, highly conservative values of the static Frictional Resistance between soil and structure are used in design. Not much emphasis has been given lately to evaluate static Frictional Resistance between soil and structure. In this study, a well graded sand, as per USCS classification system, was prepared in the laboratory at different relative densities and moisture contents i.e. dry and saturated, and Frictional Resistances of those soils were measured. Those soil samples were also sheared against wood, concrete, and steel blocks and corresponding soil–structure Frictional Resistances were measured. Moreover, similar experiments were performed for saturated and loose poorly graded sand (SP), silty sand (SM) and poorly graded sand with silt (SP–SM). The study result shows that the difference between Frictional Resistance of soil and skin friction depends on the type of soil, relative density and the moisture content. Interestingly, shear envelopes for soil–soil and soil–structure shearing Resistance exhibited curvature. The traditionally adopted soil–structure Frictional Resistance values adopted by various geotechnical manuals were found to be highly conservative.
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Influence of Relative Density on Static Soil–Structure Frictional Resistance of Dry and Saturated Sand
Geotechnical and Geological Engineering, 2013Co-Authors: Binod Tiwari, Ahmed Raad Al-adhadhAbstract:Soil–structure Frictional Resistance is required while designing foundation systems and retaining walls. Although much more attention has been paid in recent years regarding soil–structure interaction for dynamic loading, highly conservative values of the static Frictional Resistance between soil and structure are used in design. Not much emphasis has been given lately to evaluate static Frictional Resistance between soil and structure. In this study, a well graded sand, as per USCS classification system, was prepared in the laboratory at different relative densities and moisture contents i.e. dry and saturated, and Frictional Resistances of those soils were measured. Those soil samples were also sheared against wood, concrete, and steel blocks and corresponding soil–structure Frictional Resistances were measured. Moreover, similar experiments were performed for saturated and loose poorly graded sand (SP), silty sand (SM) and poorly graded sand with silt (SP–SM). The study result shows that the difference between Frictional Resistance of soil and skin friction depends on the type of soil, relative density and the moisture content. Interestingly, shear envelopes for soil–soil and soil–structure shearing Resistance exhibited curvature. The traditionally adopted soil–structure Frictional Resistance values adopted by various geotechnical manuals were found to be highly conservative.
Jian Zhou - One of the best experts on this subject based on the ideXlab platform.
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analysis of natural circulation Frictional Resistance characteristics in rod bundle channel
Annals of Nuclear Energy, 2019Co-Authors: Yinxing Zhang, Wayne W Kinnison, Peng Ji, Jian ZhouAbstract:Abstract A considerable amount of research has gone into understanding the thermal-hydraulics characteristics of rod bundle channels which is of great importance for the nuclear industry. This paper will show that the development of the correlation of the Frictional Resistance coefficient in rod bundle channels under natural circulation conditions is well understood. This paper presents experimental studies of the single-phase Resistance and obtains an improved correlation of the Frictional Resistance coefficient under natural circulation conditions based upon thermal-hydraulics characteristics which are well understood. It is also shown that this newly developed correlation closely predicts data. The experimental results show that the Frictional Resistance coefficient of a rod bundle channel under natural circulation is related to the physical properties of fluid and the size of the rod bundle channel. According to different flow regions, the relationship between the Frictional Resistance coefficient and Reynolds number is discussed separately, and the expressions of Frictional Resistance coefficient with Reynolds number in laminar flow region and transition region are obtained. After considering the influence of fluid properties on the Frictional Resistance coefficient, this paper introduces the kinematic viscosity correction factor to correct the Frictional Resistance coefficient. Finally, the complete expression of the Frictional Resistance coefficient was obtained. This newly developed predictive expression is in good agreement with experimental data in both the laminar and transition flow regions, with a relative error within ±5%. Thus we now have a predictor of the Frictional Resistance coefficient under natural circulation conditions based upon more complete thermal-hydraulic parameters in a static state.
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analysis of natural circulation Frictional Resistance characteristics in a rod bundle channel under rolling motion conditions
Experimental Thermal and Fluid Science, 2019Co-Authors: Yinxing Zhang, Wayne W Kinnison, Chong Chen, Jian ZhouAbstract:Abstract In order to study the Frictional Resistance characteristics of a rod bundle channel under ocean conditions, a natural circulation experiment was performed in a 3 × 3 rod bundle channel under rolling conditions. The characteristics of the instantaneous Frictional Resistance coefficient in the rod bundle channel under rolling conditions are obtained by analyzing newly obtained experimental data. The experimental results show that the Frictional Resistance coefficient varies with the rolling conditions. The larger the rolling amplitude and frequency, the larger the average value of the Frictional Resistance coefficient, and the greater the fluctuation of the coefficient. It is also affected by the fluid property parameters. The hotter the fluid in the channel, and the faster the fluid velocity, which means the larger heating power and the steady state Reynolds number, cause the coefficient to decrease, and the fluctuation of the coefficient will also decrease. A new correlation function of the instantaneous Frictional Resistance coefficient under differing rolling conditions is developed and compared with these newly presented data. The correlation function is a good predictor of the Frictional Resistance coefficient and is in good agreement with the experimental results over a broader range of conditions than previous functions and is also applicable for both laminar and transitions fluid flow. This new correlation function introduces the viscosity correction factor based upon the previous research, which makes it more widely applicable in predicting the instantaneous Frictional Resistance coefficient under rolling conditions. This newly developed function should be useful for design considerations for passive cooling for sea-based nuclear reactor cores.
E H Davies - One of the best experts on this subject based on the ideXlab platform.
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the influence of bracket material ligation force and wear on Frictional Resistance of orthodontic brackets
Journal of Orthodontics, 1993Co-Authors: O Keith, S P Jones, E H DaviesAbstract:AbstractPlanar static Frictional phenomena were investigated for two types of ceramic and one type of stainless steel orthodontic bracket against rectangular stainless steel archwire. The brackets studied were ‘Starfire’ (single crystal aluminium oxide), ‘Allure III’ (polycrystalline aluminium oxide), and ‘Dentaurum’ (stainless steel). The investigative parameters were: bracket material, force of ligation and whether the brackets were new or ‘worn’.Without exception, both types of ceramic bracket produced greater Frictional Resistance than the stainless steel brackets throughout testing. At a ligation force of 500 g, the Starfire bracket gave the greatest Frictional Resistance. At ligation forces of 200 and 50 g, the greatest Frictional Resistance was seen with Allure III. After a period of simulated wear, Frictional Resistance of Starfire tended to increase at the greatest ligation load while that of both ceramics decreased slightly at the two lower ligation loads. The ceramic brackets caused abrasive we...
Yinxing Zhang - One of the best experts on this subject based on the ideXlab platform.
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analysis of natural circulation Frictional Resistance characteristics in rod bundle channel
Annals of Nuclear Energy, 2019Co-Authors: Yinxing Zhang, Wayne W Kinnison, Peng Ji, Jian ZhouAbstract:Abstract A considerable amount of research has gone into understanding the thermal-hydraulics characteristics of rod bundle channels which is of great importance for the nuclear industry. This paper will show that the development of the correlation of the Frictional Resistance coefficient in rod bundle channels under natural circulation conditions is well understood. This paper presents experimental studies of the single-phase Resistance and obtains an improved correlation of the Frictional Resistance coefficient under natural circulation conditions based upon thermal-hydraulics characteristics which are well understood. It is also shown that this newly developed correlation closely predicts data. The experimental results show that the Frictional Resistance coefficient of a rod bundle channel under natural circulation is related to the physical properties of fluid and the size of the rod bundle channel. According to different flow regions, the relationship between the Frictional Resistance coefficient and Reynolds number is discussed separately, and the expressions of Frictional Resistance coefficient with Reynolds number in laminar flow region and transition region are obtained. After considering the influence of fluid properties on the Frictional Resistance coefficient, this paper introduces the kinematic viscosity correction factor to correct the Frictional Resistance coefficient. Finally, the complete expression of the Frictional Resistance coefficient was obtained. This newly developed predictive expression is in good agreement with experimental data in both the laminar and transition flow regions, with a relative error within ±5%. Thus we now have a predictor of the Frictional Resistance coefficient under natural circulation conditions based upon more complete thermal-hydraulic parameters in a static state.
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analysis of natural circulation Frictional Resistance characteristics in a rod bundle channel under rolling motion conditions
Experimental Thermal and Fluid Science, 2019Co-Authors: Yinxing Zhang, Wayne W Kinnison, Chong Chen, Jian ZhouAbstract:Abstract In order to study the Frictional Resistance characteristics of a rod bundle channel under ocean conditions, a natural circulation experiment was performed in a 3 × 3 rod bundle channel under rolling conditions. The characteristics of the instantaneous Frictional Resistance coefficient in the rod bundle channel under rolling conditions are obtained by analyzing newly obtained experimental data. The experimental results show that the Frictional Resistance coefficient varies with the rolling conditions. The larger the rolling amplitude and frequency, the larger the average value of the Frictional Resistance coefficient, and the greater the fluctuation of the coefficient. It is also affected by the fluid property parameters. The hotter the fluid in the channel, and the faster the fluid velocity, which means the larger heating power and the steady state Reynolds number, cause the coefficient to decrease, and the fluctuation of the coefficient will also decrease. A new correlation function of the instantaneous Frictional Resistance coefficient under differing rolling conditions is developed and compared with these newly presented data. The correlation function is a good predictor of the Frictional Resistance coefficient and is in good agreement with the experimental results over a broader range of conditions than previous functions and is also applicable for both laminar and transitions fluid flow. This new correlation function introduces the viscosity correction factor based upon the previous research, which makes it more widely applicable in predicting the instantaneous Frictional Resistance coefficient under rolling conditions. This newly developed function should be useful for design considerations for passive cooling for sea-based nuclear reactor cores.
