Browsing by Subject "Turbulence"
Now showing items 1-20 of 246
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123-321 models of classical novae
(EDP Sciences, 2020-01-28)
Article
Open Access
Covenantee: Università di PisaContext. High-resolution spectroscopy has revealed large concentrations of CNO and sometimes other intermediate-mass elements (e.g., Ne, Na, Mg, or Al, for ONe novae) in the shells ejected during nova outbursts, suggesting ... -
A characteristic length scale for density gradients in supercritical monocomponent flows near pseudoboiling
(2020-12)
Research report
Open Access -
A conservative overlap method for multi-block parallelization of compact finite-volume schemes
(Elsevier, 2017-12)
Article
Open AccessA conservative approach for MPI-based parallelization of tridiagonal compact schemes is developed in the context of multi-block finite-volume methods. For each block, an enlarged linear system is solved by overlapping a ... -
A data-driven wall-shear stress model for LES using gradient boosted decision trees
(Springer Nature, 2021)
Conference report
Open AccessWith the recent advances in machine learning, data-driven strategies could augment wall modeling in large eddy simulation (LES). In this work, a wall model based on gradient boosted decision trees is presented. The model ... -
A framework for estimating epistemic uncertainty in LES closures
(2016)
Research report
Open Access -
A measure of flow vorticity with twisted beams of light
(Curran, 2016)
Conference report
Restricted access - publisher's policyThe measurement of vorticity, a parameter providing local measurements of rotation at every point in a flow, would greatly assist research fields as diverse as biology microfluidics, complex motions in the oceanic and ... -
A new subgrid characteristic length for turbulence simulations on anisotropic grids
(2017-11-29)
Article
Open AccessDirect numerical simulations of the incompressible Navier-Stokes equations are not feasible yet for most practical turbulent flows. Therefore, dynamically less complex mathematical formulations are necessary for coarse-grained ... -
A numerical strategy to compute optical parameters in turbulent flow: application to telescopes
(2008-07-29)
Article
Open AccessWe present a numerical formulation to compute optical parameters in a turbulent air flow. The basic numerical formulation is a large eddy simulation (LES) of the incompressible Navier-Stokes equations, which are approximated ... -
A numerical study on turbulence generation and decay in a suddenly stopped Taylor Couette flow
(Universitat Politècnica de Catalunya, 2022-07-06)
Bachelor thesis
Open AccessIn this study are presented the numerical results obtained when simulating the abruptly stoppage of the outer cylinder in a Taylor-Couette system where the inner cylinder is static. The results are compared with the ... -
A priori study of subgrid-scale features in turbulent Rayleigh-Bénard convection
(2017-10-06)
Article
Open AccessAt the crossroad between flow topology analysis and turbulence modeling, a priori studies are a reliable tool to understand the underlying physics of the subgrid-scale (SGS) motions in turbulent flows. In this paper, ... -
A pseudo-DNS method for the simulation of incompressible fluid flows with instabilities at different scale
(Springer, 2020-01)
Article
Open AccessIn this work, a new model for the analysis of incompressible fluid flows with massive instabilities at different scales is presented. It relies on resolving all the instabilities at all scales without any additional model, ... -
A scalable geometric multigrid method for non-symmetric linear systems arising from elliptic equations
(2015)
Research report
Open Access -
A simple approach to discretize the viscous term with spatially varying (eddy-)viscosity
(2013-11-15)
Article
Restricted access - publisher's policyA simple approach to discretize the viscous dissipation term in the incompressible Navier–Stokes equations with spatially varying viscosity is presented. Unlike the case where the viscosity remains constant, its discretization ... -
Adquisición y tratamiento de datos para la caracterización de las acciones dinámicas en los disipadores de energía hidráulica
(1992-02)
Article
Open AccessLas características de tridimensionalidad, turbulencia anisotrópica y no homogénea que se presentan en el flujo de los disipadores de energía hidráulica, no permiten un estudio analítico del problema, siendo por tanto la ... -
Advanced study for the numerical resolution of the Navier-Stokes equations. Application to thermal energy storage systems
(Universitat Politècnica de Catalunya, 2022-07-19)
Master thesis
Open AccessThe resolution of the Navier Stokes equations in three dimensions in a turbulent regime applying turbulence models is studied. To accomplish this objective, it is done a brief introduction to the work done on the Final ... -
Advanced techniques for grau area mitigation in DES simulations and their effectes on the subsonic round jet acoustic spectra
(2021)
Conference report
Restricted access - publisher's policyThe research dedicated to the investigation of different gray-area mitigation approaches towards accurate aerodynamics and aeroacoustics is presented. The recent modifications of hybrid RANS-LES DDES approach based on ... -
Advances in effective flow separation control for aircraft drag reduction: modeling, simulations and experimentations
(Springer, 2020)
Book
Restricted access - publisher's policyThis book includes a collection of chosen research papers from the partners of a research project (the Seventh Framework Programme Grant Agreement (Grant Number: 266326)) named Manipulation of Reynolds Stress for Separation ... -
Aggregation of microplastic and biogenic particles in upper-ocean turbulence
(2022-12)
Article
Restricted access - publisher's policyThe aggregation of microplastic and biogenic particles in upper-ocean turbulence is studied by means of direct numerical simulations and Lagrangian tracking of point particles. The range of particle properties (size and ... -
Air distribution in street canyons: a CFD study
(Universitat Politècnica de Catalunya, 2019-06-10)
Bachelor thesis
Open AccessHeat island effect and air quality are major issues in big cities and the shape ofthe street canyons is directly related with these problems. The only presence the buildings modifies the temperature in their surroundings ... -
Algoritmos de punto de cambio aplicados a la detección de estructuras vorticosas en flujos turbulentos
(Universitat Politècnica de Catalunya. CIMNE, 2017)
Article
Open AccessEn este trabajo se presenta el análisis de la aplicación del modelo de un algoritmo de punto de cambio (Change Point Model, CPM), basado en tests no paramétricos, para la detección de estructuras turbulentas en un flujo ...