Hydrologic and hydraulic design to reduce diffuse pollution from drained peatlands

2016 ◽  
pp. 96-101
Author(s):  
S Mohammadighavam ◽  
B Kløve
Keyword(s):  
Diffuse Pollution ◽  
Hydraulic Design

Saline intrusion in deep riser outfall systems

1995 ◽  
Vol 32 (2) ◽  
pp. 175-182
Author(s):  
Roger A. Howard
Keyword(s):  
Physical Model ◽  
Recent Work ◽  
Saline Intrusion ◽  
Deep Tunnel ◽  
Hydraulic Design ◽  
Novel Methods

Saline intrusion can seriously affect the performance of outfall systems and an understanding of the mechanisms causing intrusion is important in the hydraulic design of outfalls, particularly for deep riser tunnelled outfalls. The paper outlines the reasons for the occurrence of saline intrusion, the problems that arise when it is present and the methods available for prevention and purging. The paper draws on recent work undertaken on the design of a major deep tunnel outfall system using a physical model and outlines some novel methods devised for purging of the system.

The Assessment of the Diffuse Pollution from Agricultural Territories in the Upper Volga Basin and the Development of Measures to Reduce It: Case Study of the Yakhroma River

2020 ◽  
Vol 47 (5) ◽  
pp. 709-720
Author(s):  
L. V. Kireycheva ◽  
E. A. Lentyaeva ◽  
A. D. Timoshkin ◽  
V. M. Yashin
Keyword(s):  
Diffuse Pollution ◽  
Volga Basin ◽  
Upper Volga

Theory and application of two-dimension viscous hydraulic design of the ultra-low specific-speed centrifugal pump

2019 ◽  
Vol 234 (1) ◽  
pp. 58-71 ◽  
Author(s):  
Cong Wang ◽  
Yongxue Zhang ◽  
Hucan Hou ◽  
Zhiyi Yuan
Keyword(s):  
Boundary Layer ◽  
Centrifugal Pump ◽  
Diagnostic Model ◽  
Two Dimension ◽  
Cavitation Performance ◽  
Hydraulic Design ◽  
Displacement Thickness ◽  
Low Specific Speed ◽  
Specific Speed ◽  
Low Efficiency

Low efficiency and bad cavitation performance restrict the development of the ultra-low specific-speed centrifugal pump (ULSSCP). In this research, combined turbulent boundary layer theory with two-dimension design and two-dimension viscous hydraulic design method has been proposed to redesign a ULSSCP. Through the solution of the displacement thickness in the boundary layer, a less curved blade profile with a larger outlet angle was obtained. Then the hydraulic and cavitation performance of the reference pump and the designed pump were numerically studied. The comparison of performance of the reference pump calculated by the numerical and experimental results revealed a better agreement. Research shows that the average hydraulic efficiency and head of the designed pump improve by 2.9% and 3.3%, respectively. Besides, the designed pump has a better cavitation performance. Finally, through the internal flow analysis with entropy production diagnostic model, a 24.8% drop in head loss occurred in the designed pump.

Optimal hydraulic design of an ultra-low specific speed centrifugal pump based on the local entropy production theory

2019 ◽  
Vol 233 (6) ◽  
pp. 715-726 ◽  
Author(s):  
Hucan Hou ◽  
Yongxue Zhang ◽  
Xin Zhou ◽  
Zhitao Zuo ◽  
Haisheng Chen
Keyword(s):  
Entropy Production ◽  
Centrifugal Pump ◽  
Orthogonal Design ◽  
High Energy ◽  
Geometrical Parameters ◽  
Production Theory ◽  
Local Entropy ◽  
Hydraulic Design ◽  
Low Specific Speed ◽  
Specific Speed

The ultra-low specific speed centrifugal pump has been widely applied in aerospace engineering, metallurgy, and other industrial fields. However, its hydraulic design lacks specialized theory and method. Moreover, the impeller and volute are designed separately without considering their coupling effect. Therefore, the optimal design is proposed in this study based on the local entropy production theory. Four geometrical parameters are selected to establish orthogonal design schemes including blade outlet setting angle, wrapping angle volute inlet width, and throat area. Subsequently, a 3D steady flow with Reynolds stress turbulent model and energy equation model is numerically conducted and the entropy production is calculated by a user-defined function code. The range analysis is made to identify the optimal scheme indicating that the combination of local entropy production and orthogonal design is feasible on pump optimization. The optimal pump is visibly improved with an increase of 1.08% in efficiency. Entropy production is decreased by 16.75% and 6.03% in impeller and volute, respectively. High energy loss areas are captured and explained in terms of helical vortex and wall friction, and the turbulent and wall entropy production are respectively reduced by 3.82% and 14.34% for the total pump.

Stochastic modelling of solute mass discharge to identify potential source zones of groundwater diffuse pollution

2021 ◽  
pp. 117240
Author(s):  
Licia C. Pollicino ◽  
Loris Colombo ◽  
Giovanni Formentin ◽  
Luca Alberti
Keyword(s):  
Stochastic Modelling ◽  
Diffuse Pollution ◽  
Potential Source ◽  
Source Zones ◽  
Mass Discharge

Benefits of Compiling and Analyzing Hydraulic-Design Data for Bridges

2021 ◽  
pp. 036119812110237
Author(s):  
Stephen T. Benedict ◽  
Thomas P. Knight
Keyword(s):  
South Carolina ◽  
Bridge Scour ◽  
Hydraulic Characteristics ◽  
Bridge Design ◽  
Design Data ◽  
Data Set ◽  
Engineering Knowledge ◽  
Hydraulic Design ◽  
Strong Measure ◽  
Design Characteristics

The hydraulic design of bridges is a discipline that requires a strong measure of engineering judgment. Developing good engineering judgment can take years of experience, and generally increases one project at a time. A supplemental tool that can promote the development of engineering knowledge and judgment is to compile, analyze, and graphically present hydraulic data associated with stream and bridge-design characteristics from previously analyzed bridges. If the data set is sufficiently large, graphs developed from such an effort can provide the engineer with an enhanced picture of stream and bridge-design characteristics, helping them further develop their engineering knowledge and judgment. Furthermore, such graphs can function as project scoping tools and hydraulic-design review tools. Using selected data from approximately 300 bridge-scour studies in South Carolina, previously conducted by the U.S. Geological Survey, and limited hydraulic bridge-design data for approximately 200 bridges in South Carolina, trends in stream and bridge-hydraulic characteristics were evaluated including channel width, floodplain width, flood flow depths, stream slopes, bridge backwater, bridge flow velocity, and bridge lengths. Selected relationships are presented in this paper and should serve as a valuable tool for better understanding stream and bridge-hydraulic characteristics in South Carolina.

Monitoring of diffuse pollution from agriculture to support implementation of the WFD and the Nitrate Directive in Estonia

2008 ◽  
Vol 11 (2) ◽  
pp. 185-193 ◽  
Author(s):  
Arvo Iital ◽  
Karin Pachel ◽  
Johannes Deelstra
Keyword(s):  
Diffuse Pollution

scholarly journals Toward Decentralised Sanitary Sewage Collection Systems: A Multiobjective Approach for Cost-Effective and Resilient Designs

Water ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 1886
Author(s):  
Arezoo Zahediasl ◽  
Amin E. Bakhshipour ◽  
Ulrich Dittmer ◽  
Ali Haghighi
Keyword(s):  
Treatment Plant ◽  
Drainage System ◽  
Cost Effective ◽  
Optimization Approach ◽  
Hydraulic Design ◽  
Multiobjective Approach ◽  
Layout Generation ◽  
Plant Allocation ◽  
Problem Solving Process

In recent years, the concept of a centralized drainage system that connect an entire city to one single treatment plant is increasingly being questioned in terms of the costs, reliability, and environmental impacts. This study introduces an optimization approach based on decentralization in order to develop a cost-effective and sustainable sewage collection system. For this purpose, a new algorithm based on the growing spanning tree algorithm is developed for decentralized layout generation and treatment plant allocation. The trade-off between construction and operation costs, resilience, and the degree of centralization is a multiobjective problem that consists of two subproblems: the layout of the networks and the hydraulic design. The innovative characteristics of the proposed framework are that layout and hydraulic designs are solved simultaneously, three objectives are optimized together, and the entire problem solving process is self-adaptive. The model is then applied to a real case study. The results show that finding an optimum degree of centralization could reduce not only the network’s costs by 17.3%, but could also increase its structural resilience significantly compared to fully centralized networks.

Teaching of Hydraulic Design at University of Newcastle upon Tyne

2001 ◽  
Vol 127 (12) ◽  
pp. 1009-1012 ◽  
Author(s):  
P. Novak ◽  
E. M. Valentine
Keyword(s):  
Hydraulic Design ◽  
Newcastle Upon Tyne
Sign in / Sign up

Export Citation Format

Share Document