Numerical modeling of solid particles motion in suspensions using Smoothed Particle Hydrodynamics

Mobilization of solid particles at the interface between a porous and a free flow domain is a relevant subject in many fields of mechanical, civil and environmental engineering. One example is the initiation of sediment transport as it appears in river beds. To approximate this initiation state, various theoretical models exist. Common approaches use two‐domain formulations as in [1] or one‐domain formulations as in [6]. The named approaches were compared with Direct Numerical Simulations (DNS) using Smoothed Particle Hydrodynamics (SPH) in [3]. The results of these simulations showed that the theoretical models often underestimate the occurring velocities at the interface and therefore critical velocities to initialize the motion of single grains can be lower than predicted by theoretical approaches. In our numerical simulations, we study creeping flow in a free flow domain coupled to flow in a porous media applying various porous structures. To investigate velocities and shear stresses at the interface more intensively we then compare our numerical results to data from experiments that were performed on equivalent microstructures. (© 2017 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)

The 13th International Scientific Conference of Civil and Environmental Engineering for the PhD. students and young scientists below 35 years - Young Scientists 2021 (YS21) under auspices of- assoc. prof. Peter Mésároš, the dean of the Civil Engineering Faculty of the Technical University of Košice,- Ing. Andrej Doležal, the Minister of Transport and Construction of the Slovak Republic,- Mgr. Branislav Gröhling, the Minister of Education, Science, Research and Sport of the Slovak Republic, and- Ján Budaj, the Minister of Environment of the Slovak Republic,was held in Štrbské Pleso, the High Tatras, Slovakia on 13th - 15th October 2021. The traditional meeting of PhD. students, their supervisors and young scientists working in the field of civil and environmental engineering was organised by the Faculty of Civil Engineering, the Technical University of Košice, Slovakia.The Young Scientist 2021 offered an international platform for the dissemination of the original research results. It provides a pleasant environment to present a new, great ideas of young researchers and discovered advances in the field of civil and environmental engineering and related interdisciplinary topics. The conference provided an opportunity for PhD. students and young researchers to discussed scientific topics and research results, to share their knowledge and experiences, to collaborate in innovative designs and proposals.List of Editors, Committees, Review Statement are available in this pdf.

9 December 2021 (Online conference) Editors:Zul-Atfi Ismail, Fahmi Muhammad Ridwan, Che Zulzikrami Azner Abidin, Nur Soleha Abdul Rahim, Noor Ainee Zainol, Nurfadzillah Ishak Organiser:Faculty of Civil Engineering Technology, Universiti Malaysia Perlis, Perlis, Malaysia PREFACE International Conference on Civil and Environmental Engineering (CENVIRON2021) is the fourth CENVIRON conducted since the first conference in 2017. The initial purpose of the conference is to gather researchers, academia and industries in a platform to exchange views, share ideas and discuss current researches in the field of civil and environmental engineering. This include current research and development especially in the advancement of various scope related fundamentals and applications. This conference is expected to spur a fruitful debate and discussion, scientifically bring fresh ideas and at the same time, create a networking opportunity and strong collaboration between the participants.Due to the COVID 19 pandemic, unfortunately, we have reached an agreement to opt for a virtual conference instead of the planned physical conference in the metropolitan city of Penang, Malaysia. Since the pandemic in Malaysia is still unstable and shows no sign of settling soon, and no mass gathering is allowed, this would be the best choice as to put everyone’s health a priority. Despite that, our team has managed to meet regularly via face to face discussions and virtual meetings, in order to ensure the quality of the conference and manuscript is not compromised.The conference was officiated on 9th December 2021 by the UniMAP’s Vice Chancellor, Prof. Dr. Zaliman Sauli at Auditorium of UniMAP Chancellory Building with minimal physical attendees among the conference organizing committee member to allow for social distancing, and with more than 60 attendees following through Google meet platform. The opening ceremony was broadcasted live via UniMAP’s official Facebook page.Two esteemed keynote speakers were invited for the plenary sessions, i.e., Dato’ Seri Ir. Dr. Zaini Ujang (Secretary General, Ministry of Energy, Green Technology and Water Malaysia) and the Dato’ Ir. Haji Mohamad Zulkefly Sulaiman (Director General, Public Work Department Malaysia).The online parallel sessions were successfully organised at Tuanku Syed Faizuddin Putra Library, Universiti Malaysia Perlis (UniMAP) using Google Meet platform. Researchers, academicians and students are among the viewers of the virtual conference. The parallel sessions were conducted according to the theme of publication. Details of the presentation schedule were included in the upcoming section. Each parallel session was chaired by an academician in the related field of Civil and Environmental Engineering to ensure smooth and lively discussions. Each session took about 15 minutes of presentation and 5 minutes of Q&A. Overall, 70 papers were accepted for CENVIRON2021 after rigorous peer review process.In summary, the success of the conference is a team effort. I am grateful to all the committee members who worked very hard to make this event a successful one. We would also like to thank all the authors who submitted their papers to the conference, and the reviewers who contributed to the review process, ensuring quality publication of the conference proceedings. We hope that you will find this conference thought provoking and engrossing and that you had a valuable experience sharing ideas with others at this conference.On behalf of the Organizing Committee,Ir. Dr. Mohd Zulham Affandi Mohd Zahid,CENVIRON2021 ChairmanList of Keynote Speakers are available in this pdf.

The importance of integrating the Sustainable Development Goals (SDG) in the curriculum of all the bachelor and master degrees at UPC has been legally and institutionally recognised. At the Barcelona School of Civil Engineering, issues such as professional ethics, environmental impacts of infrastructures, respect for cultural diversity and gender perspective are currently cross-cutting competences highlighted and stated in the study plans as a transversal competence on Sustainability and Social Commitment (S&SC). However, its effective implementation requires significant teaching efforts in order to adapt academic curricula, so far limited to individual non- coordinated initiatives. The launch of the “ODS-Camins Toolkit” project (Toolkit for the Promotion of SDG in the Civil and Environmental Engineering Fields) seeks to encourage the implementation of teaching innovation practices that contribute to the deployment and assessment of S&CS competences. The aim of the project is to exchange experiences, develop new practices, and draft a common pathway for the promotion and implementation of the SDGs in the field of civil and environmental engineering studies. The paper will explain the experience of this one-year project, highlighting barriers, challenges, and sharing the lessons learned with the final purpose of involving all the community in the years to come. It will also present the Toolkit for the Promotion of SDGs in the Civil and Environmental Engineering Fields

A splitting integration scheme for the SPH simulation of concentrated particle suspensions

Coupling total Lagrangian SPH–EISPH for fluid–structure interaction with large deformed hyperelastic solid bodies

A new fluid–solid interface algorithm for simulating fluid structure problems in FGM plates

Digital Rocks Portal (www.digitalrocksportal.org) Digital Rocks is a data portal for fast storage and retrieval of images of varied porous micro-structures. It has the purpose of enhancing research resources for modeling/prediction of porous material properties in the fields of Petroleum, Civil and Environmental Engineering as well as Geology. This platform allows managing and preserving available images of porous materials and experiments performed on them, and any accompanying measurements (porosity, capillary pressure, permeability, electrical, NMR and elastic properties, etc.) required for both validation on modeling approaches and the upscaling and building of larger (hydro)geological models.

Environmental engineers support the well-being of people and the planet in areas where the two intersect. Over the decades the field has improved countless lives through innovative systems for delivering water, treating waste, and preventing and remediating pollution in air, water, and soil. These achievements are a testament to the multidisciplinary, pragmatic, systems-oriented approach that characterizes environmental engineering. The future holds daunting challenges for human society and our environment. Populations are expanding, demand for resources is increasing, the climate is changing, and humanity’s impacts on the planet continue to mount. Will we be able to achieve a better quality of life for our growing population without compromising the ability of future generations to achieve the same? This study, authored by 18 of the nation’s leading environmental engineers, scientists, and policy experts under the auspices of the National Academies of Sciences, Engineering, and Medicine, outlines the crucial role for environmental engineers in this period of dramatic growth and change. The report identifies five pressing challenges of the 21st century that environmental engineers are uniquely poised to help advance: 1: Sustainably supply food, water, and energy 2: Curb climate change and adapt to its impacts 3: Design a future without pollution and waste 4: Create efficient, healthy, resilient cities 5: Foster informed decisions and actions The report’s vision is ambitious. The challenges ahead are substantial. Yet every day, environmental engineers are making progress, both by applying existing knowledge and skills and by advancing research and innovation to generate new insights and achievements. By refocusing and redoubling its efforts to advance practical, impactful solutions for humanity’s multifaceted, vexing problems, the field of environmental engineering can build on its past successes—and chart new territory—in the decades ahead.

Liquefaction can result in the damage or collapse of structures during an earthquake and can therefore be a great threat to life and property. Many site investigations of liquefaction disasters are needed to study the large-scale deformation and flow mechanisms of liquefied soils that can be used for performance assessments and infrastructure improvement. To overcome the disadvantages of traditional flow analysis methods for liquefied soils, a soil–water-coupled smoothed particle hydrodynamics (SPH) modeling method was developed to analyze flow in liquefied soils. In the proposed SPH method, water and soil were simulated as different layers, while permeability, porosity, and interaction forces could be combined to model water-saturated porous media. A simple shear test was simulated using the SPH method with an elastic model to verify its application to solid phase materials. Subsequently, the applicability of the proposed SPH modeling method to the simulation of interaction forces between water and soil was verified by a falling-head permeability test. The coupled SPH method produced good simulations for both the simple shear and falling-head permeability tests. Using a fit-for-purpose experimental apparatus, a physical flow model test of liquefied sand has been designed and conducted. To complement the physical test, a numerical simulation has been undertaken based on the soil–water-coupled SPH method. The numerical results correspond well with the physical model test results in observed configurations and velocity vectors. An embankment failure in northern Sweden was selected so that the application of the soil–water-coupled SPH method could be extended to an actual example of liquefaction. The coupled SPH method simulated the embankment failure with the site investigation well. They have also estimated horizontal displacements and velocities, which can be used to greatly improve the seismic safety of structures.

We present the application of the smoothed particle hydrodynamics (SPH) discretization scheme to Phillips' model for shear-induced particle migration in concentrated suspensions. This model provides an evolution equation for the scalar mean volume fraction of idealized spherical solid particles of equal diameter which is discretized by the SPH formalism. In order to obtain a discrete evolution equation with exact conservation properties we treat in fact the occupied volume of the solid particles as the degree of freedom for the fluid particles. We present simulation results in two- and three-dimensional channel flow. The two-dimensional results serve as a verification by a comparison to analytic solutions. The three-dimensional results are used for a comparison with experimental measurements obtained from computer tomography of injection moulded ceramic microparts. We observe the best agreement of measurements with snapshots of the transient simulation for a ratio D(c)/D(η)=0.1 of the two model parameters.

Coupled SPH-DEM simulations of liquefaction-induced flow failure

Field tracer tests indicate that advective porosity, the quantity relating advective velocity to Darcy flux, may exhibit directional dependence. Theory (S. P. Neuman, 2005) suggests that directional variations in advective porosity could arise from incomplete mixing of an inert tracer between directional flow channels within a sampling volume of soil or rock that may be hydraulically isotropic or anisotropic, rendering advective porosity a function of Peclet number. Whereas Neuman was able to quantify the process for idealized intersecting fracture sets, his theory is too abstract to allow doing so for more complex systems of fractures or pores. We use Smoothed Particle Hydrodynamics (e.g., A. M. Tartakovsky and P. Meakin, 2005, 2006) to simulate advective‐diffusive transport of a passive tracer in the interior of an idealized pore space between impermeable circular or elliptical solid grains of random size, arranged randomly within a square domain. Our numerical experiments reveal a transition from complete mixing of tracer at small Peclet numbers to the gradual evolution of pore‐scale channels of tracer which allow less and less mixing as Peclet numbers grow. Advective porosity, computed as the ratio between total water flux across the domain boundaries and migration rate of the tracer center of mass, is found to diminish asymptotically from a value close to the total porosity at small Peclet numbers to a constant dominated entirely by advection at large Peclet numbers. When total porosity is kept constant, channeling is less pronounced and mixing more prominent when flow takes place parallel to the longer axes of elliptical grains as compared to when the grains are circular. On the other hand, channeling is more pronounced and mixing less so when flow takes place perpendicular to the longer elliptical grain axes. Correspondingly, the rate at which advective porosity diminishes with increasing Peclet number is slower and the asymptote is larger when flow takes place parallel to the longer axes of elliptical grains than when the grains are circular. However, the rate is faster and the asymptote smaller when flow takes place perpendicular to the longer elliptical grain axes.

SummaryThis paper presents a model which can be used for fast landslides where coupling between solid and pore fluid plays a fundamental role. The proposed model is able to describe debris flows where the difference of velocities between solid grains and fluid is important. The approach is based on the mathematical model proposed by Zienkiewicz and Shiomi, which is similar to those of Pitman and Le and Pudasaini. The novelty of the present work is the numerical technique used, the smoothed particle hydrodynamics (SPH). We propose to use a double set of nodes for soil and water phases, the interaction between them being described by a suitable drag law. The paper presents both mathematical and numerical models, describing the main assumptions and their limitations. Then, the model is applied to (1) a simple case where shocks and expansion waves appear, (2) a dam break problem on a horizontal plane with a frictional soil phase, and (3) a debris flow which happened in Hong Kong. The main conclusions that can be drawn from the applications are: Debris flows having 2 phases with important relative mobility present a rich structure of shocks and rarefaction waves, which has to be properly modeled. Otherwise, the model will have numerical damping or dispersion. Dambreak exercises provide interesting information in simple and controlled situations. We can see how both phases move relative to each other. Real debris flows can be simulated with the proposed model, obtaining reasonable results.

Numerical ability of hyperbolic flux solvers to compute 2D shear layers in turbulent shallow flows