Browsing by Subject "Calor -- Convecció"
Now showing items 1-20 of 31
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A comparison of high-order time integrators for highly supercritical thermal convection in rotating spherical shells
(2014-01-10)
Article
Restricted access - publisher's policyThe efficiency of implicit and semi-implicit time integration codes based on backward differentiation and extrapolation formulas for the solution of the three-dimensional Boussinesq thermal convection equations in rotating ... -
Advanced study for the numerical approximation of Navier-Stokes equations by implementation of a finite volume solver
(Universitat Politècnica de Catalunya, 2019-10)
Bachelor thesis
Restricted access - author's decision
Covenantee: Rheinisch-Westfälische Technische Hochschule AachenThe objective of the thesis is to build different fluid solvers from scratch, whereby the following three cases are considered: Resolution of diffusion problems, convection-diffusion and Navier-Stokes equations. In the ... -
Antisymmetric polar modes of thermal convection in rotating spherical fluid shells at high Taylor numbers
(2008-11-03)
Article
Open AccessThe onset of thermal convection in a rotating spherical shell of intermediate radius ratio ¼ 0:4 is studied numerically for Taylor numbers Ta 1011 and the Prandtl number of the liquid sodium ( ¼ 0:01). For the first ... -
Computation of azimuthal waves and their stability in thermal convection in rotating spherical shells with application to the study of a double-Hopf bifurcation
(2013-03-22)
Article
Open AccessA methodology to compute azimuthal waves, appearing in thermal convection of a pure fluid contained in a rotating spherical shell, and to study their stability is presented. It is based on continuation, Newton-Krylov, and ... -
Continuation of double Hopf points in thermal convection of rotating fluid spheres
(2021-01-26)
Article
Open AccessThe thermal convection of rotating fluids in spherical geometry is a classical problem with application to many geophysical and astrophysical problems. The study of the transition to periodic solutions from the steady ... -
Direct numerical simulation of laminar and turbulent Rayleigh-Bénard convection
(Universitat Politècnica de Catalunya / Universitat de Barcelona, 2013-06)
Master thesis
Open AccessThe main aim of this work is understanding the phenomenon of B enard cells in laminar and turbulent regimes as an application of studying the air flow in the air gap and honey comb cells that installed in the flat plate ... -
Direct numerical simulation of the turbulent natural convection flow in an open cavity of aspect ratio 4
(Begell House, 2012)
Conference report
Open AccessIn this paper, three-dimensional turbulent natural convection heat transfer in an open cavity with an isothermal wall facing the overture has been studied. The aspect ratio chosen for the cavity has been 4 to complement the ... -
DNS and regularization modeling of a turbulent differentially heated cavity of aspect ratio 5
(2013-01-15)
Article
Open AccessThis work is devoted to the study of turbulent natural convection flows in differentially heated cavities. The adopted configuration corresponds to an airfilled (Pr = 0.7) cavity of aspect ratio 5 and Rayleigh number Ra ... -
Effect of using external vertical fins in phase change material modules for domestic hot water tanks
(2006-04)
Article
Open AccessThe effect of using external vertical fins in Phase Change Materials (PCM) modules to improve the natural convection coefficient in water is studied in this paper. The use of PCM in a water tank working with a solar system ... -
Exponential versus IMEX high-order time integrators for thermal convection in rotating spherical shells
(2014-01-24)
Article
Open AccessWe assess the accuracy and efficiency of several exponential time integration methods coupled to a spectral discretization of the three-dimensional Boussinesq thermal convection equations in rotating spherical shells. ... -
Film boiling heat transfer from micro heat sinks driven by Bénard-Marangoni convection
(2021-01-26)
External research report
Open AccessBénard-Marangoni convection and its significance with regard to film boiling heat transfer from micro heat sinks is discussed. In recent works cooling performance of micro heat sinks has been studied showing that two-phase ... -
Large eddy and direct numerical simulations of a turbulent water-filled differentially heated cavity of aspect ratio 5
(2014-10-01)
Article
Open AccessNatural convection in a differentially heated cavity is characterized by different phenomena such as laminar to turbulent flow transition in the boundary layer, turbulent mixing, and thermal stratification in the core of ... -
Localized pinning states in closed containers: homoclinic snaking without bistability
(2009-08)
Article
Open AccessBinary mixtures with a negative separation ratio are known to exhibit time-independent spatially localized convection when heated from below. Numerical continuation of such states in a closed two-dimensional container with ... -
Moisture statistics in free convective boundary layers growing into linearly stratified atmospheres
(2017-07-27)
Article
Open AccessWe use dimensional analysis and direct numerical simulations to characterize specific humidity statistics in the equilibrium (quasi-steady) entrainment regime of cloud-free convective boundary layers that grow into ... -
Numerical simulation of the air flow inside a cavity combiner of the ALBA Synchrotron
(Universitat Politècnica de Catalunya, 2015-07)
Bachelor thesis
Restricted access - author's decisionThe main objective of the project is to simulate the air flow inside a cavity combiner of ALBA Synchrotron and its cooling efficiency as accurately as possible. For that, the thermal energy exchange inside of the cavity ... -
Numerical simulations of thermal convection in rotating spherical shells under laboratory conditions
(2014-03-05)
Article
Restricted access - publisher's policyAn exhaustive study, based on numerical three-dimensional simulations, of the Boussinesq thermal convection of a fluid confined in a rotating spherical shell is presented. A moderately low Prandtl number fluid (ro = 0.1) ... -
On the feasibility of affordable high-fidelity CFD simulations for indoor environment design and control
(2020-10-15)
Article
Restricted access - publisher's policyComputational fluid dynamics (CFD) is a reliable tool for indoor environmental applications. However, accurate CFD simulations require large computational resources, whereas significant cost reduction can lead to unreliable ... -
On the onset of low Prandtl number convection in rotating spherical shells: non-slip boundary conditions
(2008-01-15)
Article
Open AccessAccurate numerical computations of the onset of thermal convection in wide rotating spherical shells are presented. Low-Prandtl-number (σ) fluids, and non-slip boundary conditions are considered. It is shown that at small ... -
On thermocapillary rings from radioactive particles suspended at the surface of liquids
(2019-07)
Article
Restricted access - publisher's policyThermocapillary motion and its significance with regard the thermal behavior of heat sources and with particular reference to radioactive particles suspended in fluids is discussed. It shown that because the heat source, ... -
Oscillatory convection in rotating spherical shells: low Prandtl number and non-slip boundary conditions
(2015-10-01)
Article
Open AccessA five-degree model, which reproduces faithfully the sequence of bifurcations and the type of solutions found through numerical simulations of the three-dimensional Boussinesq thermal convection equations in rotating ...
