Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
5.5
3.4
Journals
Water
Special Issues
Transient Flows: Mathematical Models, Laboratory Tests, Protection Elements and Systems
share announcement

Transient Flows: Mathematical Models, Laboratory Tests, Protection Elements and Systems

A special issue of Water (ISSN 2073-4441). This special issue belongs to the section "Hydraulics and Hydrodynamics".

Deadline for manuscript submissions: 15 August 2024 | Viewed by 8592

Special Issue Editor

Prof. Dr. Vicente S. Fuertes-Miquel

E-Mail Website
Guest Editor
Department of Hydraulic Engineering and Environment, Polytechnic University of Valencia, 46022 Valencia, Spain
Interests: water distribution systems; hydraulic transients; hydraulic elements; fluid facilities inside buildings
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Transient flows represent a field of research that has advanced greatly in the last few decades. However, there are still many aspects of transient flows that require further research. Transient flows result from sudden changes in flow conditions in pipeline systems because of planned or accidental maneuvers. Failures related to the effects of transient flows can lead to major accidents and significant damage to pipeline systems. At present, transient flows analysis is a fundamental part of the design of fluid systems.

Transient flows analysis is a complex research topic. In recent years, considerable progress has been made due to developments in computer science, numerical models, and novel analysis techniques. This Special Issue focuses on all advancements related to transient flows, mathematical simulations, new analysis techniques, computational fluid dynamics (CFD), laboratory tests, protection elements and systems against water hammer, innovative strategies for controlling water hammer, hydraulic transients with entrapped air, hydraulic transients with water column separation, the consequences and risks of hydraulic transients, etc. This Special Issue aims to collect novel research related to transient flows in any subject.

Prof. Dr. Vicente S. Fuertes-Miquel
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Water is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • transient flows 
  • unsteady flow 
  • pressure surges 
  • water hammer 
  • numerical simulation 
  • computational fluid dynamics (CFD) 
  • laboratory tests 
  • dynamic behavior 
  • protection elements and systems

Published Papers (5 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

19 pages, 12948 KiB  
Article
Development of Pipeline Transient Mixed Flow Model with Smoothed Particle Hydrodynamics Based on Preissmann Slot Method
by Yixin Yang, Hexiang Yan, Shixun Li, Wenke Song, Fei Li, Huanfeng Duan, Kunlun Xin and Tao Tao
Water 2024, 16(8), 1108; https://doi.org/10.3390/w16081108 - 12 Apr 2024
Viewed by 459
Abstract
The accurate modeling and understanding of complex transient mixed pipe flows is crucial for the optimal design and safe and efficient operation in pipeline systems such as urban drainage systems. Currently, the predominant approach for modeling free-surface-pressurized flows relies on grid-based numerical schemes, [...] Read more.
The accurate modeling and understanding of complex transient mixed pipe flows is crucial for the optimal design and safe and efficient operation in pipeline systems such as urban drainage systems. Currently, the predominant approach for modeling free-surface-pressurized flows relies on grid-based numerical schemes, with comparatively limited capability for exploring its complex phenomena. This study proposed a novel one-dimensional numerical model that integrates the smoothed particle hydrodynamics (SPH) method with the Preissmann slot method (PSM) to explore transient mixed flows in pipeline systems, with better potential capability for exploring more mixed flow phenomena. Empirical parameters of the proposed SPH-PSM model were optimized for improving the numerical accuracy and stability, and the applicable range for these empirical parameters was recommended. The performances of the proposed model were evaluated by different flow regimes, including one free surface case, one fully pressurized case, and two transient mixed-flow cases. The simulation results of different flow regimes demonstrated a high level of agreement with the reference data, indicating the good capability of the SPH-PSM model in simulating complex flow regimes in pipeline systems. Therefore, the proposed SPH-PSM model can be an alternative way for modeling, exploring, and understanding the complex transient mixed flows in pipeline systems. Full article
(This article belongs to the Special Issue Transient Flows: Mathematical Models, Laboratory Tests, Protection Elements and Systems)
►▼ Show Figures

Figure 1

12 pages, 2395 KiB  
Article
Analyzing Water Leakages in Parallel Pipe Systems with Rapid Regulating Valve Maneuvers
by Vicente S. Fuertes-Miquel, Alfonso Arrieta-Pastrana and Oscar E. Coronado-Hernández
Water 2024, 16(7), 926; https://doi.org/10.3390/w16070926 - 22 Mar 2024
Viewed by 626
Abstract
Water utilities face the challenge of addressing physical leaks generated from the aging of water distribution systems and the need for more innovative practices to manage water infrastructure efficiently. Water leakages are typically modeled using extended period simulations based on Bernoulli’s equation. However, [...] Read more.
Water utilities face the challenge of addressing physical leaks generated from the aging of water distribution systems and the need for more innovative practices to manage water infrastructure efficiently. Water leakages are typically modeled using extended period simulations based on Bernoulli’s equation. However, this approach must be revised since traditional methods do not appropriately simulate variations induced by regulating valves. In this study, the authors developed a mathematical model based on the mass oscillation equation, which is well-suited for predicting water leakages while accounting for system inertia from regulating valves. This approach is versatile and can be applied to all parallel pipe systems. A comprehensive practical application involving two parallel pipes has been conducted. The aim is to provide engineers and designers with a tool to assess the total volume of water leaks caused by regulating valves in real-world water distribution networks. Furthermore, the study includes a comparative analysis with a single pipe configuration to illustrate how parallel systems lead to increased leaks in contrast to simpler pipe setups. Full article
(This article belongs to the Special Issue Transient Flows: Mathematical Models, Laboratory Tests, Protection Elements and Systems)
►▼ Show Figures

Figure 1

30 pages, 6346 KiB  
Article
Application of Machine Learning Coupled with Stochastic Numerical Analyses for Sizing Hybrid Surge Vessels on Low-Head Pumping Mains
by Ahmed M. A. Sattar, Abedalkareem Nedal Ghazal, Mohamed Elhakeem, Amgad S. Elansary and Bahram Gharabaghi
Water 2023, 15(19), 3525; https://doi.org/10.3390/w15193525 - 09 Oct 2023
Viewed by 1822
Abstract
In surge protection, low-head profiles are deemed a challenge in pump failure events since they are prone to severe negative pressure surges that require an uneconomical surge vessel volume. A hybrid surge vessel with a dipping tube can provide required protection with reasonable [...] Read more.
In surge protection, low-head profiles are deemed a challenge in pump failure events since they are prone to severe negative pressure surges that require an uneconomical surge vessel volume. A hybrid surge vessel with a dipping tube can provide required protection with reasonable economic volume. This work presents novel analyses for the hybrid surge vessel and develops a simple model for its optimum sizing using a stochastic numerical approach coupled with machine learning. Practical ranges for correct sizing of vessel components, such as ventilation tube, inlet/outlet air valves, and compression chamber, are presented for optimal protection and performance. The water hammer equations are iteratively solved using the hybrid surge vessel’s revised boundary conditions within the method of characteristics numerical framework to generate 2000 cases representing real pump failures on low-head pipelines. Genetic programming is utilized to develop simple relations for prediction of the hybrid vessel initial and expanded air volumes in addition to the compression chamber volume. Moreover, the developed model presented a classification index for low-head pipelines on which the hybrid vessel would be most economical. The developed model yielded good prediction error statistics. The developed model proves to be more accurate and easier to use than the classical design charts for the low-head pumping mains. The model clearly showed the relation between various hydraulic and pipe parameters, with pipe diameter and static head as the most influencing parameters on compression chamber volume and expanded air volume. The developed model, together with the classification indices, can be used for preliminary surge protection sizing for low-head pipelines. Full article
(This article belongs to the Special Issue Transient Flows: Mathematical Models, Laboratory Tests, Protection Elements and Systems)
►▼ Show Figures

Figure 1

18 pages, 2530 KiB  
Article
Smoothed Particle Hydrodynamics Simulations of Porous Medium Flow Using Ergun’s Fixed-Bed Equation
by Carlos E. Alvarado-Rodríguez, Lamberto Díaz-Damacillo, Eric Plaza and Leonardo Di G. Sigalotti
Water 2023, 15(13), 2358; https://doi.org/10.3390/w15132358 - 26 Jun 2023
Viewed by 1450
Abstract
A popular equation that is often employed to represent the relationship between the pressure loss and the fluid flow in fluidized or packed granular beds is the Ergun equation, which is an extension of Darcy’s law. In this paper, the method of Smoothed [...] Read more.
A popular equation that is often employed to represent the relationship between the pressure loss and the fluid flow in fluidized or packed granular beds is the Ergun equation, which is an extension of Darcy’s law. In this paper, the method of Smoothed Particle Hydrodynamics (SPH) is used to numerically study the flow field across a rectangular channel partially filled with a porous layer both at the Representative Elementary Volume (REV) scale using the Ergun equation and at the pore scale. Since the flow field can be estimated at the REV scale with a much lower cost compared to the pore scale, it is important to evaluate how accurately the pore-scale results can be reproduced at the REV scale. The comparison between both scales is made in terms of the velocity profiles at the outlet of the rectangular channel and the pressure losses across the clear and porous zones for three different arrays of solid grains at the pore scale. The results show that minimum differences in the flow structure and velocity profiles between the REV and the pore scale always occur at intermediate values of the porosity (ϕ=0.44 and 0.55). As the porosity increases, the differences between the REV and the pore scale also increase. The details of the pressure losses are affected by the geometry of the porous medium. In particular, we find that the pressure profiles at the REV scale match those at the pore scale almost independently of the porosity only when the grains are uniformly distributed in a non-staggered square array. Full article
(This article belongs to the Special Issue Transient Flows: Mathematical Models, Laboratory Tests, Protection Elements and Systems)
►▼ Show Figures

Figure 1

15 pages, 6277 KiB  
Article
Application of Newton–Raphson Method for Computing the Final Air–Water Interface Location in a Pipe Water Filling
by Dalia M. Bonilla-Correa, Óscar E. Coronado-Hernández, Vicente S. Fuertes-Miquel, Mohsen Besharat and Helena M. Ramos
Water 2023, 15(7), 1304; https://doi.org/10.3390/w15071304 - 26 Mar 2023
Cited by 1 | Viewed by 3580
Abstract
The estimation of thermodynamic behavior during filling processes with entrapped air in water pipelines is a complex task as it requires solving a system of algebraic-differential equations. A lot of different numerical methods have been used for this purpose in literature including the [...] Read more.
The estimation of thermodynamic behavior during filling processes with entrapped air in water pipelines is a complex task as it requires solving a system of algebraic-differential equations. A lot of different numerical methods have been used for this purpose in literature including the rigid water column (RWC) model. The main advantage of the RWC model is its acceptable accuracy with very low computational load. In that context, this research presents the computation of critical points of the physical equations that describe the phenomenon. These points provide information about the final position of the air–water interface. The Newton–Raphson method was then applied to obtain a unique equation that can be used by engineers to directly compute variables such as air pocket pressure and water column length at the end of the hydraulic event. A case study was analyzed to compare the results of the mathematical model with the obtained equation for computing critical points. Both methods provided the same values for the water column length at the end of the hydraulic event. A sensitivity analysis was conducted to identify dependent and non-dependent parameters for evaluating the critical points. The proposed formulation was validated through an experimental set of data. Full article
(This article belongs to the Special Issue Transient Flows: Mathematical Models, Laboratory Tests, Protection Elements and Systems)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-5
Back to TopTop