Ricardo B. Canelas

Bio: Ricardo B. Canelas is an academic researcher from Instituto Superior Técnico. The author has contributed to research in topics: Solver & Smoothed-particle hydrodynamics. The author has an hindex of 11, co-authored 33 publications receiving 859 citations.

DualSPHysics: Open-source parallel CFD solver based on Smoothed Particle Hydrodynamics (SPH)

Abstract: DualSPHysics is a hardware accelerated Smoothed Particle Hydrodynamics code developed to solve free-surface flow problems. DualSPHysics is an open-source code developed and released under the terms of GNU General Public License (GPLv3). Along with the source code, a complete documentation that makes easy the compilation and execution of the source files is also distributed. The code has been shown to be efficient and reliable. The parallel power computing of Graphics Computing Units (GPUs) is used to accelerate DualSPHysics by up to two orders of magnitude compared to the performance of the serial version. Program summary Program title: DualSPHysics Catalogue identifier: AEUS_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEUS_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: GNU General Public License No. of lines in distributed program, including test data, etc.: 121,399 No. of bytes in distributed program, including test data, etc.: 12,324,308 Distribution format: tar.gz Programming language: C++ and CUDA. Computer: Tested on CPU Intel X5500 and GPUs: GTX 480, GTX 680, Tesla K20 and GTX Titan. Operating system: Any system with a C++ and NVCC compiler, tested on Linux distribution Centos 6.5 CUDA: Tested on versions 4.0, 4.1, 4.2, 5.0 and 5.5 with driver version 331.38. Has the code been vectorised or parallelised?: Different threads of CPU or number of cores of GPU. RAM: Tens of MB to several GB, depending on problem Classification: 4.12. Nature of problem: The DualSPHysics code has been developed to study free-surface flows requiring high computational cost. Solution method: DualSPHysics is an implementation of Smoothed Particle Hydrodynamics, which is a Lagrangian meshless particle method. Running time: 6 h on 8 processors of Intel X5500 (15 min on GTX Titan) for the dam-break case with 1 million particles simulating 1.5 s of physical time (more than 26,000 steps).

Dam-break flows over mobile beds: experiments and benchmark tests for numerical models

Abstract: In this paper, the results of a benchmark test launched within the framework of the NSF–PIRE project “Modelling of Flood Hazards and Geomorphic Impacts of Levee Breach and Dam Failure” are presented. Experiments of two-dimensional dam-break flows over a sand bed were conducted at Universite catholique de Louvain, Belgium. The water level evolution at eight gauging points was measured as well as the final bed topography. Intense scour occurred close to the failed dam, while significant deposition was observed further downstream. From these experiments, a benchmark was proposed to the scientific community, consisting of blind test simulations, that is, without any prior knowledge of the measurements. Twelve different teams of modellers from eight countries participated in the study. Here, the numerical models used in this test are briefly presented. The results are commented upon, in view of evaluating the modelling capabilities and identifying the challenges that may open pathways for further research.

SPH-DCDEM model for arbitrary geometries in free surface solid-fluid flows

Abstract: A unified discretization of rigid solids and fluids is introduced, allowing for resolved simulations of fluid–solid phases within a meshless framework. The numerical solution, attained by Smoothed Particle Hydrodynamics (SPH) and a variation of Discrete Element Method (DEM), the Distributed Contact Discrete Element Method (DCDEM) discretization, is achieved by directly considering solid–solid and solid–fluid interactions. The novelty of the work is centred on the generalization of the coupling of the DEM and SPH methodologies for resolved simulations, allowing for state-of-the-art contact mechanics theories to be used in arbitrary geometries, while fluid to solid and vice versa momentum transfers are accurately described. The methods are introduced, analysed and discussed. Initial validations on the DCDEM and the fluid coupling are presented, drawing from test cases in the literature. An experimental campaign serves as a validation point for complex, large scale solid–fluid flows, where a set of blocks in several configurations is subjected to a dam-break wave. Blocks are tracked and positions are then compared between experimental data and the numerical solutions. A Particle Image Velocimetry (PIV) technique allows for the quantification of the flow field and direct comparison with numerical data. The results show that the model is accurate and is capable of treating highly complex interactions, such as transport of debris or hydrodynamic actions on structures, if relevant scales are reproduced.

A Smooth Particle Hydrodynamics discretization for the modelling of free surface flows and rigid body dynamics

Abstract: Summary This work describes a unified discretization of rigid solids and fluids, allowing for spatially detailed and time-resolved simulations of fluid–solid interaction. The model is based on a Smoothed Particle Hydrodynamics (SPH) discretization of the Navier–Stokes equations and Newton's equations for rigid body dynamics. A δ-SPH term is added to the continuity equation, allowing for an effective interface description. The benchmark case of the buoyancy-driven motion of an unrestricted rigid body allows for experimenting new computational approaches for the more general case of fluid–solid interactions, in the case of solid objects larger than the smallest flow scales. Numerical experiments and analytical solutions are recovered from the literature and compared with the numerical results from the proposed model. Experimental measurements were performed and numerical results are compared, resulting in a wide range study of the fundamental properties of fluid–solid systems. After an investigation on the influence of the stabilizing δ-SPH terms, the model is shown to respect free stream consistency, the correct dynamics of a buoyant body, for a range of positive and negative relative densities and the correct recovery of equilibrium states. This work addresses these topics in an attempt to characterise the presented model with regard to the quality of its solutions and possible limitations. Copyright © 2015 John Wiley & Sons, Ltd.

State-of-the-art SPH solver DualSPHysics: from fluid dynamics to multiphysics problems.

Abstract: DualSPHysics is a weakly compressible smoothed particle hydrodynamics (SPH) Navier-Stokes solver initially conceived to deal with coastal engineering problems, especially those related to wave impact with coastal structures. Since the first release back in 2011, DualSPHysics has shown to be robust and accurate for simulating extreme wave events along with a continuous improvement in efficiency thanks to the exploitation of hardware such as graphics processing units (GPUs) for scientific computing or the coupling with wave propagating models such as SWASH and OceanWave3D. Numerous additional functionalities have also been included in the DualSPHysics package over the last few years which allow the simulation of fluid-driven objects. The use of the discrete element method (DEM) has allowed the solver to simulate the interaction among different bodies (sliding rocks, for example), which provides a unique tool to analyse debris flows. In addition, the recent coupling with other solvers like Project Chrono or MoorDyn has been a milestone in the development of the solver. Project Chrono allows the simulation of articulated structures with joints, hinges, sliders and springs and MoorDyn allows simulating moored structures. Both functionalities make DualSPHysics one of the meshless model world leaders in the simulation of offshore energy harvesting devices. Lately, the present state of maturity of the solver goes beyond single phase simulations, allowing multi-phase simulations with gas-liquid and a combination of Newtonian and non-Newtonian models expanding further the capabilities and range of applications for the DualSPHysics solver. These advances and functionalities make DualSPHysics a state-of-the-art meshless solver with emphasis on free-surface flow modelling.

The physical oceanography of the transport of floating marine debris

Abstract: Marine plastic debris floating on the ocean surface is a major environmental problem. However, its distribution in the ocean is poorly mapped, and most of the plastic waste estimated to have entered the ocean from land is unaccounted for. Better understanding of how plastic debris is transported from coastal and marine sources is crucial to quantify and close the global inventory of marine plastics, which in turn represents critical information for mitigation or policy strategies. At the same time, plastic is a unique tracer that provides an opportunity to learn more about the physics and dynamics of our ocean across multiple scales, from the Ekman convergence in basin-scale gyres to individual waves in the surfzone. In this review, we comprehensively discuss what is known about the different processes that govern the transport of floating marine plastic debris in both the open ocean and the coastal zones, based on the published literature and referring to insights from neighbouring fields such as oil spill dispersion, marine safety recovery, plankton connectivity, and others. We discuss how measurements of marine plastics (both in situ and in the laboratory), remote sensing, and numerical simulations can elucidate these processes and their interactions across spatio-temporal scales.

Smoothed particle hydrodynamics (SPH) for free-surface flows: past, present and future

Abstract: This paper assesses some recent trends in the novel numerical meshless method smoothed particle hydrodynamics, with particular focus on its potential use in modelling free-surface flows. Due to its Lagrangian nature, smoothed particle hydrodynamics (SPH) appears to be effective in solving diverse fluid-dynamic problems with highly nonlinear deformation such as wave breaking and impact, multi-phase mixing processes, jet impact, sloshing, flooding and tsunami inundation, and fluid–structure interactions. The paper considers the key areas of rapid progress and development, including the numerical formulations, SPH operators, remedies to problems within the classical formulations, novel methodologies to improve the stability and robustness of the method, boundary conditions, multi-fluid approaches, particle adaptivity, and hardware acceleration. The key ongoing challenges in SPH that must be addressed by academic research and industrial users are identified and discussed. Finally, a roadmap is propose...

Smoothed particle hydrodynamics method for fluid flows, towards industrial applications: Motivations, current state, and challenges

Abstract: Smoothed Particle Hydrodynamics (SPH) is a relatively new meshless numerical approach which has attracted significant attention in the last two decades. Compared with the conventional mesh-based computational fluid dynamics (CFD) methods, the SPH approach exhibits some unique advantages in modeling multiphysic flows and associated transport phenomena due to its capabilities of handling complex boundary evolution as well as modeling complicated physics in a relatively simple manner. On the other hand, as SPH is still a developing CFD method, it is crucial to identify its advantages and limitations in modeling realistic multiphysic flow problems of real life and of industrial interest. Toward this end, this work aims at summarizing the motivations behind utilizing the SPH method in an industrial context, making the state-of-the-art of the present application of this method to industrial problems, as well as deriving general conclusions regarding its assets and limitations and stressing the remaining challenges in order to make it an hand-on computational tool.

On the state-of-the-art of particle methods for coastal and ocean engineering

Abstract: The article aims at providing an up-to-date review on several latest advancements related to particle methods with applications in coastal and ocean engineering. The latest advancements corresponding to accuracy, stability, conservation properties, multiphase multi-physics multi-scale simulations, fluid-structure interactions, exclusive coastal/ocean engineering applications and computational efficiency are reviewed. The future perspectives for further enhancement of applicability and reliability of particle methods for coastal/ocean engineering applications are also highlighted.

An enhanced ISPH–SPH coupled method for simulation of incompressible fluid–elastic structure interactions

Abstract: An enhanced fully-Lagrangian meshfree computational method is developed for simulating incompressible fluid–elastic structure interactions. The developed method corresponds to a SPH (Smoothed Particle Hydrodynamics)-based coupled FSI (Fluid–Structure Interaction) solver. Coupling is conducted in between a projection-based ISPH (Incompressible SPH) fluid model and a newly developed SPH-based structure model in a mathematically–physically consistent manner. Fluid model is founded on the solution of Navier–Stokes and continuity equations while structure model is set on conservation laws for linear and angular momenta corresponding to an isotropic elastic solid. A set of previously developed enhanced schemes are incorporated for the ISPH fluid model, hence, the developed coupled method is referred to as Enhanced ISPH–SPH. The performance of SPH-based structure model is first validated in reproduction of benchmark tests including dynamic response of a free oscillating cantilever plate and stress distribution inside an isotropic plate with a circular opening. Then the Enhanced ISPH–SPH is scrupulously verified through simulations of FSI problems including hydrostatic water column on an elastic plate, dam break with an elastic gate, sloshing in tanks with elastic baffles and hydroelastic slammings of an elastic aluminum wedge and a marine panel. To the best knowledge of the authors, this paper presents the first semi-implicit/explicit ISPH–SPH coupled method for FSI related to deformable elastic structures with comprehensive validations and performance investigations.