The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Sheng Cheng - One of the best experts on this subject based on the ideXlab platform.
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coefficients of local head losses in steady state flow of throttled surge tanks with standpipe by cfd
Advanced Materials Research, 2013Co-Authors: Jian Feng An, Sheng ChengAbstract:This study investigates the steady-state flow pattern of throttled surge tanks with standpipe, especially the coefficients of local head losses. The experiments were carried out, and FLUENT, which solves the Reynolds-averaged Navier-Stokes equations, was applied to experimental data for solving flow fields. The results show the computed and measured local head losses agree closely. The coefficients of the local head losses are linearly proportional to diameter ratio with the slope of 0.037. The anticlockwise backflow region occurs in the standpipe, and it induces inflow into and outflow from the standpipe. For Hydraulic Engineering projects, the discharge into and out from standpipe does not change with velocity and diameter of main conduit, but are linearly proportional to diameter ratio with the slope of 0.0378.
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coefficients of local head losses in steady state flow of throttled surge tanks with standpipe by cfd
Advanced Materials Research, 2013Co-Authors: Jian Feng An, Sheng ChengAbstract:This study investigates the steady-state flow pattern of throttled surge tanks with standpipe, especially the coefficients of local head losses. The experiments were carried out, and FLUENT, which solves the Reynolds-averaged Navier-Stokes equations, was applied to experimental data for solving flow fields. The results show the computed and measured local head losses agree closely. The coefficients of the local head losses are linearly proportional to diameter ratio with the slope of 0.037. The anticlockwise backflow region occurs in the standpipe, and it induces inflow into and outflow from the standpipe. For Hydraulic Engineering projects, the discharge into and out from standpipe does not change with velocity and diameter of main conduit, but are linearly proportional to diameter ratio with the slope of 0.0378.
Zhenzi Li - One of the best experts on this subject based on the ideXlab platform.
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maximum twin shear stress factor criterion for crack sliding initiation
International Conference on Innovative Computing Information and Control, 2007Co-Authors: Jialin Ji, Huijian Li, Zhenzi LiAbstract:In civil Engineering, Hydraulic Engineering and so, the shear fracture phenomena of concrete material exists extensively. So the fracture criterion of the crack tip mixed mode deformation has been one of the important problems of fracture mechanics of concrete. In the present study, a maximum twin shear stress factor criterion for mixed slide mode fracture initiation is proposed. By concrete subjected to shear box test, this criterion is in agreement with experimental results of the cleavage angle.
Donald W Knight - One of the best experts on this subject based on the ideXlab platform.
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an attempt at using the entropy approach to predict the transverse distribution of boundary shear stress in open channel flow
Stochastic Environmental Research and Risk Assessment, 2002Co-Authors: Mark Sterling, Donald W KnightAbstract:This paper highlights the similarities between a number of studies which have applied the concept of Shannon's entropy to Hydraulic Engineering. The entropy concept is further developed in an attempt to predict the transverse distribution of boundary shear stress in circular open channels. The approach is also extended and applied to circular channels with a flat bed and trapezoidal channels, and the Lagrange multipliers, λ, found by recourse to empirical equations. Doubts are expressed concerning the value of the entropy approach to such problems.
Jianqiao Han - One of the best experts on this subject based on the ideXlab platform.
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combined effects of multiple large scale Hydraulic Engineering on water stages in the middle yangtze river
Geomorphology, 2017Co-Authors: Jianqiao Han, Zhaohua Sun, Yunping YangAbstract:Abstract Investigation of water stages influenced by human projects provides better understanding of riverine geomorphological processes and river management. Based on hydrological data collected over ~ 60 years, an extreme stage-extreme discharge analysis and a specific-gauge analysis were performed to research the individual and combined effects of multiple Engineering projects on a long-term time series of water stages in the middle Yangtze River. Conclusions are as follows. (1) In accordance with the operation years of the Jingjiang cutoff (CF), the Gezhouba Dam (GD), and the Three Gorges Dam (TGD), the time series (1955–2012) was divided into periods of P1 (1955–1970), P2 (1971–1980), P3 (1981–2002), and P4 (2003 − 2012). Water stage changes during P1–P2, P2–P3, and P3–P4 are varied because of the differences in the types and scales of these projects. The stage decreased at Shashi and increased at Luoshan owing to the operation of the CF. Additionally, after the GD was constructed, the low-flow stage decreased in the upstream reach of Chenglingji and increased in its downstream reach, whereas the flood stage merely decreased at Yichang. Moreover, the TGD resulted in an overall decrease in low-flow stages and a limited increase in flood stages because of the differential adjustments of river geometry and resistance between the low-flow channel and flood channel. (2) Although differences existed in the scouring mechanisms between streamwise erosion associated with dams and headward erosion associated with cutoffs, particular bed textures in the gravel reach led to a similar adjustment that stage reduction at Shashi was the greatest of all stations, which caused the flow slope and sediment transport capacity to decrease in the sandy reach. (3) These Engineering projects caused changes in average low-flow and flood stages that varied between Yichang (− 1.58 and − 0.08 m respectively), Shashi (− 3.54 and − 0.12 m), and Luoshan (1.15 and 0.97 m) from P1 to P4. However, less influence was observed at Hankou owing to its remote location and the short impoundment time of the TGD. (4) Potentially detrimental decreases in low-flow stages and increases in flood stages should be monitored and managed in the future. Our results are of practical significance for river management and the evaluation of the influences of large-scale anthropogenic activities on the hydrological regimes of large rivers.
Andrew J Stolba - One of the best experts on this subject based on the ideXlab platform.
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field imaging and volumetric reconstruction of riprap rock and large sized aggregates algorithms and application
Transportation Research Record, 2019Co-Authors: Haohang Huang, Jiayi Luo, Maziar Moaveni, Erol Tutumluer, John Hart, Sheila Beshears, Andrew J StolbaAbstract:Riprap rock and large-sized aggregates have been used extensively in geotechnical and Hydraulic Engineering. They essentially provide erosion control, sediment control, and scour protection. The su...
