Hydraulic performance of sewer pipes with deposited sediments

2008 ◽  
Vol 57 (11) ◽  
pp. 1743-1748 ◽  
Author(s):  
Robert Banasiak
Keyword(s):  
Discharge Capacity ◽  
Laboratory Study ◽  
Hydraulic Performance ◽  
Experimental Results ◽  
Cohesive Sediments ◽  
Sewer Pipes ◽  
Friction Characteristics ◽  
Study Results ◽  
Bed Forms ◽  
Sediment Deposit

This paper investigates in-sewer sediment deposit behaviour and its influence on the hydraulic performance of sewer pipes. This evaluation is based on experimental results regarding the mobility of non-cohesive and partly cohesive deposits in a partially full circular pipe. The focus of these tests is on the development of bed forms and friction characteristics. In particular, it is investigated to what extent the bed forms from the non-cohesive and (partly) cohesive sediments affect a sewer's discharge capacity. Based on the laboratory study results and on the existing criteria for sewer design, a generic assessment of a sewer's hydraulic performance is made. The relative discharge factor for a pipe with sediment deposit is analysed in terms of the thickness and roughness of the deposit.

scholarly journals Two-Dimensional Numerical Modeling of Flow in Physical Models of Rock Vane and Bendway Weir Configurations

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 458
Author(s):  
Drew C. Baird ◽  
Benjamin Abban ◽  
S. Michael Scurlock ◽  
Steven B. Abt ◽  
Christopher I. Thornton
Keyword(s):  
Numerical Modeling ◽  
Physical Model ◽  
Numerical Models ◽  
Hydraulic Performance ◽  
Physical Models ◽  
Protection Measures ◽  
Design Engineers ◽  
Model Study ◽  
Study Results ◽  
Wide Range

While there are a wide range of design recommendations for using rock vanes and bendway weirs as streambank protection measures, no comprehensive, standard approach is currently available for design engineers to evaluate their hydraulic performance before construction. This study investigates using 2D numerical modeling as an option for predicting the hydraulic performance of rock vane and bendway weir structure designs for streambank protection. We used the Sedimentation and River Hydraulics (SRH)-2D depth-averaged numerical model to simulate flows around rock vane and bendway weir installations that were previously examined as part of a physical model study and that had water surface elevation and velocity observations. Overall, SRH-2D predicted the same general flow patterns as the physical model, but over- and underpredicted the flow velocity in some areas. These over- and underpredictions could be primarily attributed to the assumption of negligible vertical velocities. Nonetheless, the point differences between the predicted and observed velocities generally ranged from 15 to 25%, with some exceptions. The results showed that 2D numerical models could provide adequate insight into the hydraulic performance of rock vanes and bendway weirs. Accordingly, design guidance and implications of the study results are presented for design engineers.

scholarly journals A Laboratory Study for Erosional Properties of Cohesive Sediments from Mokpo Coast

2011 ◽  
Vol 25 (1) ◽  
pp. 14-21 ◽  
Author(s):  
Man-Kon Kim ◽  
Su-Hyun Yang ◽  
Dong-Hyeon Tae ◽  
Kyu-Nam Hwang
Keyword(s):  
Laboratory Study ◽  
Cohesive Sediments

Laboratory study of sand bed forms induced by solitary waves in shallow water

2005 ◽  
Vol 110 (F4) ◽  
pp. n/a-n/a ◽  
Author(s):  
François Marin ◽  
Nizar Abcha ◽  
Jérôme Brossard ◽  
Alexander B. Ezersky
Keyword(s):  
Shallow Water ◽  
Solitary Waves ◽  
Laboratory Study ◽  
Bed Forms

scholarly journals Reconfigurable equilibrium circuit with additional power supply

2019 ◽  
Vol 15 (1) ◽  
pp. 106-111 ◽  
Author(s):  
Yu Zhang ◽  
Mingming Huang ◽  
Tiezhou Wu ◽  
Feng Ji
Keyword(s):  
Single Cell ◽  
Conversion Efficiency ◽  
Discharge Capacity ◽  
Power Supply ◽  
State Of Charge ◽  
Experimental Results ◽  
Battery Pack ◽  
Number Of Components ◽  
Better Than

Abstract The reconfigurable equilibrium circuit can take account of the number of components and the conversion efficiency and can easily balance every single cell in the battery pack, but the voltage of the battery pack will fluctuate when the battery pack is balanced. To solve this problem, a reconfigurable equalization circuit with an additional power supply is proposed. By replacing the cell with the additional power supply, the purpose of stabilizing the voltage of the battery pack is achieved. Aiming at the additional power supply, this paper puts forward a method that the additional power supply participates in the charging (discharging) process when the SOC (state of charge) of the battery pack is not lower (higher) than the additional power supply while the battery pack is charging (discharging), to make the charge and discharge capacity of the additional power supply always better than the battery pack. The experimental results show that the proposed equalization circuit can not only retain the advantages of the traditional reconfigurable equilibrium circuit but also maintain the voltage of the battery pack in the equalization process.

Experimental identification of dynamic parameters for a class of geared robots

Robotica ◽  
1996 ◽  
Vol 14 (5) ◽  
pp. 561-574 ◽  
Author(s):  
Krzysztof R. Kozłowski ◽  
Piotr Dutkiewicz
Keyword(s):  
Experimental System ◽  
Experimental Results ◽  
Integral Model ◽  
Dynamic Parameters ◽  
Direct Drive ◽  
Friction Coefficients ◽  
Friction Characteristics ◽  
Experimental Identification ◽  
Differential Identification ◽  
Comparison Of The Results

SUMMARYThe main objective of this paper is a presentation of an experimental identification of a non-direct drive robot and load dynamic parameters, which appear in the integral model. The last one is based on the energy theorem formulation. In the robotics literature there are not many experimental results known to the authors, concerning the identification of the dynamic parameters of different models. In order to satisfy this, the experimental system has been built around an industrial ASEA IRp-6 robot. In this paper we propose to precompute the friction characteristics which are separated in the integral model. Various aspects of the exciting trajectories are considered. It is shown how to identify the friction coefficients using a short integral model. The experimental results are presented, including comparison of the results for both integral and differential identification. The identified models are verified by computing the predicted torques and trajectories

scholarly journals LABORATORY STUDY ON SAND TRANSPORT OVER RIPPLES DUE TO ASYMMETRIC OSCILLATORY FLOWS

1986 ◽  
Vol 1 (20) ◽  
pp. 109 ◽  
Author(s):  
Shinji Sato ◽  
Kiyoshi Horikawa
Keyword(s):  
Laboratory Study ◽  
Oscillatory Flow ◽  
Transport Rate ◽  
Sand Transport ◽  
Hydraulic Parameters ◽  
Oscillatory Flows ◽  
Sand Transport Rate ◽  
Bed Forms ◽  
Sand Movement

Mechanism of sand movement due to asymmetric oscillatory flows was investigated through experiments. Measurements of bed forms, suspended sand concentration and net sand transport rate were carried out by using an oscillatory flow tunnel. The process of entrainment and suspension of sand above asymmetric ripples was quantitatively described. The geometry of ripples and the net sand transport rate in regular and irregular flows were expressed in terms of hydraulic parameters characterizing the oscillatory flow. Two-dimensionality of ripples was found to be an important factor in the estimation of the net sand transport rate.

scholarly journals Effect of Corner Shape on Hydraulic Performance of One-Cycle Rectangular Labyrinth Weirs

Fluids ◽  
2020 ◽  
Vol 5 (3) ◽  
pp. 117
Author(s):  
Omed S. Q. Yousif ◽  
Moses Karakouzian
Keyword(s):  
Discharge Capacity ◽  
Hydraulic Performance ◽  
Acute Angle ◽  
Effective Length ◽  
Hydraulic Efficiency ◽  
Labyrinth Weir ◽  
Rounded Corner ◽  
Side Walls ◽  
The One ◽  
Labyrinth Weirs

The hydraulic performance of rectangular labyrinth weirs has been investigated by many researchers, however, the effects of the corner shape on the hydraulic performance of rectangular labyrinth weirs have not been addressed in the current literature. Accordingly, this experimental study aims to explore the effect of the corner shape of on discharge efficiency of rectangular labyrinth weirs. Five flat-crested rectangular labyrinth weirs, with five different corner shapes, were made of High-Density Polyethylene Plastic (HDPE) and tested in a rectangular flume. Under different overflow discharges, the discharge coefficients for the rectangular labyrinth weirs were determined. The results showed that the shape of corners for rectangular labyrinth weirs was an effective factor. For example, rounding or beveling the corners can significantly increase the discharge capacity of the rectangular labyrinth weirs. However, the rounded corner shape was slightly better than the beveled corner shape. Among all labyrinth weir models tested in this study, the rectangular labyrinth weir with a semi-circular apex showed the highest hydraulic efficiency, while the one with an acute-angle corner shape showed the lowest hydraulic efficiency. For the rectangular labyrinth weir having a semi-circular shape, although the original effective length reduced by about 14%, the discharge coefficient, CL, increased by 16.7% on average. For the rectangular labyrinth weir that has an acute-angle corner shape, although the effective length (LC) of the weir increased by 23%, its discharge capacity decreased by 35.2% on average. Accordingly, improper folding of the side-walls of the rectangular labyrinth weir led to a significant reduction in the weir’s hydraulic performance.

scholarly journals Effects of sediment deposit on the hydraulic performance of the urban stormwater drainage system

2022 ◽  
Vol 964 (1) ◽  
pp. 012020
Author(s):  
C N X Quang ◽  
N N H Giang ◽  
H V Hoa ◽  
P Q Hung
Keyword(s):  
Cross Section ◽  
Peak Flow ◽  
Drainage System ◽  
Critical Factor ◽  
Extreme Rainfall ◽  
Hydraulic Performance ◽  
Extreme Rainfall Events ◽  
Cross Section Area ◽  
Section Area ◽  
Sediment Deposit

Abstract Sediment deposit is a critical factor strongly affecting the drainage capacity of the conduits due to its cross-section area narrowing and roughness increasing. In this study, a numerical model was applied to investigate the influences of sediment deposit on the hydraulic performance of the drainage conduits. The Nhieu Loc - Thi Nghe (NL-TN) basin, located in Ho Chi Minh City, Vietnam, was selected as a case study. The drainage network of the NL-TN basin was simulated by using the EPA-SWMM model. The effects of sediment deposit were assessed by a non-dimensional comparison of the simulated peak flows of the sediment-deposited conduits and the clean ones. The results indicated that the sediment deposit significantly affects the flow capacity of the conduits and could cause severe inundation. Narrowing of the cross-section area has more impact on the hydraulic performance of the conduit than the increase in the roughness. A 40% increase in the Manning coefficient could decline the peak flow to approximately 80-90%, while a 40% increase in sediment thickness depth could degrade the peak flow by about 60-70% to compare with the peak flow of the clean conduit. The findings could support decision makings on the operation and maintenance of the sewer system and adaptation to extreme rainfall events.

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