Explanipedia

Verification and validation of blade-resolved viscous-flow tidal turbine simulations Open

Manuel Rentschler, Tiago Gomes, Guilherme Vaz, Luís Eça, Stephen R. Turnock · 2025

Tidal turbines are a renewable energy source on the rise. The exceptional predictability of tidal currents contributes to a high reliability of this technology, which represents a key advantage in the endeavor to become a major contributor…

Use of Regression to Extend ASME V&V20 Validation Metrics from Validation Points to an Application Point Open

Leonard J. Peltier, Urmila Ghia, Nima Fathi, Kevin J. Dowding, Luís Eça · 2025

Simulations based on the numerical solution of mathematical/computational models using the laws of physics have become common practice in Engineering. Establishing confidence in the quantities of interest obtained from such simulations req…

A Solution Verification Exercise for a Practical Application of a Coastal Hydrodynamics Model Open

Manuel Rentschler, Luís Eça, Guilherme Vaz · 2025

Within renewable energy resources, tidal energy stands out due to its great reliability and predictability. Meanwhile, its extraction is highly site specific. An accurate resource assessment is thus crucial for the identification and devel…

On the Challenges of Verification Exercises of Viscous Flow Simulations Open

Luís Eça · 2025

Development of a 2D Potential Flow Reduced-Order Numerical Method for the Analysis of Forces and Pressure Fields around Multiple Moving Objects or Cascades Open

Daniel Brito, Luís Eça, J. Baltazar · 2025

Errors and uncertainties in CFD validation for non-equilibrium turbulent boundary layer flows at high Reynolds numbers Open

Tobias Knopp, Luís Eça, Serge Toxopeus, Daniel Fritsch, A. Gargiulo , et al. · 2024

NATO AVT-RTG-349 was dedicated to the validation of computational fluid dynamics (CFD) methods based on the Reynolds-Averaged Navier-Stokes (RANS) equations and statistical turbulence models for non-equilibrium turbulent-boundary-layer flo…

Comparison of RANS Turbulence Models for the Simulation of Smooth Wall Boundary-Layers in Pressure Gradients at Moderate and High Reynolds Numbers Open

Luís Eça, Maarten Kerkvliet, Serge Toxopeus · 2023

Recently, experimental measurements of boundary-layers under non-equilibrium pressure gradients have been performed at Virginia Tech [1].The pressure gradient imposed to the boundary-layers is induced by a rectangular wing with a NACA 0012…

Efficiency of biradial impulse turbines concerning rotor blade angle, guide-vane deflection and blockage Open

D. Ferreira, L.M.C. Gato, Luís Eça · 2022

Self-rectifying impulse turbines have two sets of guide vanes symmetrically located on each rotor side. Aerodynamic losses resulting from the inherent misalignment between the rotor outflow and the outlet guide vanes penalize these turbine…

Verification and Validation: The Path to Predictive Scale-Resolving Simulations of Turbulence Open

Filipe S. Pereira, Fernando F. Grinstein, Daniel Israel, Luís Eça · 2022

This work investigates the importance of verification and validation (V&V) to achieve predictive scale-resolving simulations (SRSs) of turbulence, i.e., computations capable of resolving a fraction of the turbulent flow scales. Toward this…

Analysis of Hybridizable Discontinuous Galerkin Stabilization Parameter in Convection Dominated Flows Open

Hashim Elzaabalawy, Ganbo Deng, Luís Eça, Michel Visonneau · 2022

Assessment of Solving the Rans Equations with Two-Equation Eddy-Viscosity Models Using High-Order Accurate Discretization Open

Hashim Elzaabalawy, Ganbo Deng, Luís Eça, Michel Visonneau · 2022

Point-Wise Divergence-Free Extended Hybridizable Discontinuous Galerkin Method for Two-Phase Stokes Flow with Unfitted Meshes and Interfaces Open

Ahmed Sherif, Hashim Elzaabalawy, G.B. Deng, Luís Eça, Michel Visonneau · 2022

Spherical particle migration evaluation in low reynolds number couette flow using smooth profile method Open

Mahyar Pourghasemi, Nima Fathi, Peter Vorobieff, Goodarz Ahmadi, Seyed Sobhan Aleyasin , et al. · 2021

An Eulerian-Lagrangian model is developed to investigate the solid particle migration in low Reynolds number shear flows between two parallel plates.A continuous kernel function with a predefined thickness is applied in the implemented num…

Assessment of Discretization Uncertainty Estimators Based on Grid Refinement Studies Open

Luís Eça, Guilherme Vaz, M. Hoekstra, Scott W. Doebling, Robert L. Singleton , et al. · 2021

This paper presents the assessment of the performance of nine discretization uncertainty estimates based on grid refinement studies including methods that use grid triplets and others that use a largest number of data points, which in this…

Discretization Error Estimation in Subsonic, Transonic and Supersonic Flows of an Inviscid Fluid Over a Bump Open

Luís Eça, Cristiano Silva, João Muralha, C.M. Klaij, Serge Toxopeus , et al. · 2021

This paper presents a solution verification exercise for the simulation of subsonic, transonic and supersonic flows of an inviscid fluid over a circular arc (bump). Numerical simulations are performed with a pressure-based, single-phase co…

Toward Predictive RANS and SRS Computations of Turbulent External Flows of Practical Interest Open

Filipe S. Pereira, Luís Eça, Guilherme Vaz, Sharath S. Girimaji · 2021

Solution Verification Studies of a Pressure-Based Compressible Flow Solver Open

João Muralha, C. Silva, Luís Eça, Christian M. Klaij · 2021

Although considering the fluid to be incompressible is a common and valid approximation in most hydrodynamic simulations, certain phenomena like sloshing or slamming involve compressibility effects. In order to capture such effects, the ma…

Divergence-Free Extended Hybridizable Discontinuous Galerkin Method (X-HDG) For Laminar Incompressible Two-Phase Flow Open

A. M. Sherif, M. Visonneau, G.B. Deng, Luís Eça · 2021

RANS simulations for the turbulent uniform and channel flow using HDG for incompressible flow Open

Hashim Elzaabalawy, G.B. Deng, Luís Eça, Michel Visonneau · 2019

International audience

eXtended Discontinuous Galerkin (X-DG) for bi-material elliptic problem Open

Ahmed Sherif, Michel Visonneau, G.B. Deng, Luís Eça · 2019

Numerical and Parameter Uncertainties: Are They Independent? Open

Luís Eça, Rui Lopes, Filipe S. Pereira, Guilherme Vaz · 2019

In the Validation procedure proposed by the ASME V&V 20 Standard, the quantification of the modeling error of mathematical models solved by Computational Fluid Dynamics (CFD) requires the estimation of the experimental, numerical and param…

Investigating the Effect of the Closure in Partially-Averaged Navier–Stokes Equations Open

Filipe S. Pereira, Luís Eça, Guilherme Vaz · 2019

The importance of the turbulence closure to the modeling accuracy of the partially-averaged Navier–Stokes equations (PANS) is investigated in prediction of the flow around a circular cylinder at Reynolds number of 3900. A series of PANS ca…

Simulation of Wingtip Vortex Flows with Reynolds-Averaged Navier–Stokes and Scale-Resolving Simulation Methods Open

Filipe S. Pereira, Luís Eça, Guilherme Vaz · 2019

The simulation of wingtip vortex flows is reported on with Reynolds-averaged Navier–Stokes (RANS) equations and scale-resolving simulation (SRS) models. These range from turbulent viscosity and Reynolds-stress model (RSM) RANS closures, to…

Challenges in Modelling and Simulation of Turbulent Flows with Spatially-Developing Coherent Structures Open

Filipe S. Pereira, Luís Eça, Guilherme Vaz, Sharath S. Girimaji · 2017

The objective of this work is to investigate the challenges encountered in Scale-Resolving Simulations (SRS's) of turbulent wake flows driven by spatially-developing coherent structures. SRS's of practical interest are expressly intended f…

A high-order Discontinuous Galerkin Method with mesh refinement for optimal control Open

J.C.C. Henriques, João M. Lemos, Luís Eça, L.M.C. Gato, A.F.O. Falcão · 2017

A Discontinuous Galerkin Method for optimal and sub-optimal control applied to an oscillating water column wave energy converter Open

J.C.C. Henriques, João M. Lemos, Luís Eça, J.N.H. Valério, L.M.C. Gato , et al. · 2017

This paper applies a Discontinuous Galerkin (DG) finite element time-stepping method for the numerical solution of optimal and sub-optimal control problems within the framework of the Pontryagin's Maximum Principle. The local nature of the…

On the prediction of shear-layer flows with rans and SRS models Open

Guilherme Vaz, Filipe S. Pereira, Luís Eça · 2017

This study evaluates the ability of Reynolds-Averaged Navier-Stokes (RANS) and \n \nScale-Resolving Simulations (SRS) models to predict turbulent shear-layer predominant (blunt- body) \n flows. The selected cases are the flows around a ci…

On the numerical convergence properties of the calculation of the flow around the KVLCC2 tanker in unstructured grids Open

Ana Luísa Rocha, Luís Eça, Guilherme Vaz · 2017

This paper addresses the estimation of numerical errors in the calculation of the \n \nflow around the KVLCC2 tanker at model scale Reynolds number in unstructured grids. The flow \nsolution is based on the Reynolds-Averaged Navier-Stokes…

On the numerical requirements of rans and hybrid turbulence models Open

Filipe S. Pereira, Guilherme Vaz, Luís Eça · 2015

The evaluation of different mathematical models for the prediction of tur- \n \nbulent flows depends on the ability to reduce the numerical error to negligible \nlevels, \n \ni.e. to values clearly below the modelling error. In this work …

Luís Eça YOU? Author Swipe