Proceedings ArticleDOI
Direct Numerical Simulation of Rotating Cavity Flows Using a Spectral Element-Fourier Method
TLDR
In this article, a high-order numerical method is employed to investigate flow in a rotor/stator cavity without heat transfer and buoyant flow in the rotor/rotor cavity.Abstract:
A high-order numerical method is employed to investigate flow in a rotor/stator cavity without heat transfer and buoyant flow in a rotor/rotor cavity. The numerical tool used employs a spectral element discretisation in two dimensions and a Fourier expansion in the remaining direction, which is periodic and corresponds to the azimuthal coordinate in cylindrical coordinates. The spectral element approximation uses a Galerkin method to discretise the governing equations, similarly to a finite element method, but employs high-order polynomials within each element to obtain spectral accuracy. A second-order, semi-implicit, stiffly stable algorithm is used for the time discretisation, and no subgrid modelling is included in the governing equations. Numerical results obtained for the rotor/stator cavity compare favourably with experimental results for Reynolds numbers up to Re1 = 106 in terms of velocities and Reynolds stresses. For the buoyancy-driven flow, the energy equation is coupled to the momentum equations via the Boussinesq approximation, which has been implemented in the code considering two different formulations. Numerical predictions of the Nusselt number obtained using the traditional Boussinesq approximation are considerably higher than available experimental data. Much better agreement is obtained when the extended Boussinesq approximation is em-ployed. It is concluded that the numerical method employed has considerable potential for further investigations of rotating cavity flows.read more
Citations
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Journal ArticleDOI
Onset of convection induced by centrifugal buoyancy in a rotating cavity
TL;DR: In this article, the authors analyzed the onset of buoyancy in a rotating cylindrical cavity bounded by two plane insulated disks, adopting a geometrical configuration relevant to fundamental studies of buoyant-induced flows occurring in gas turbine's internal air systems.
Journal ArticleDOI
Numerical investigation of buoyancy-induced flow in a sealed rapidly rotating disc cavity
TL;DR: In this article, the authors presented buoyancy-induced flow for a sealed rotating cavity with rotational inertia in the range 10 − to 10 − 1 for an incompressible model with Boussinesq approximation, compared with a compressible gas flow model.
Journal ArticleDOI
Effect of an axial throughflow on buoyancy-induced flow in a rotating cavity
TL;DR: In this paper, large-eddy simulation is used to study buoyancy-induced flow in a rotating cavity with an axial throughflow of cooling air, where the thickness of boundary layers forming near the upstream and downstream disks is consistent with that of a laminar Ekman layer, although the boundary layer thickness distribution along the radial direction presents greater variations than in the sealed cavity case.
Proceedings ArticleDOI
Large-Eddy Simulation of Buoyancy-Induced Flow in a Sealed Rotating Cavity
TL;DR: In this paper, the authors used a high-order numerical method to perform large-eddy simulation (LES) of buoyancy-induced flows in a sealed rotating cavity with either adiabatic or heated disks.
Journal ArticleDOI
Simulations of compressibility effects in centrifugal buoyancy-induced flow in a closed rotating cavity
Deepak Saini,Richard D. Sandberg +1 more
TL;DR: In this paper, the authors investigate the effect of buoyancy-induced flow and heat transfer induced by a rapidly rotating system with direct relevance to the internal air system of a gas-turbine engine.
References
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Journal ArticleDOI
High-order splitting methods for the incompressible Navier-Stokes equations
TL;DR: Improved pressure boundary conditions of high order in time are introduced that minimize the effect of erroneous numerical boundary layers induced by splitting methods, and a new family of stiffly stable schemes is employed in mixed explicit/implicit time-intgration rules.
Book
Spectral/hp Element Methods for Computational Fluid Dynamics
TL;DR: In this article, Jacobi polynomials Gauss-type integration Collocation differentiation Co discontinuous expansion bases are used to simulate incompressible flows in one-dimensional expansion bases.
Journal ArticleDOI
Natural Convection Adjacent to Horizontal Surface of Various Planforms
J. R. Lloyd,W. R. Moran +1 more
TL;DR: In this paper, a wide range of Rayleigh numbers have been used to correlate natural convection transfer coefficients for highly unsymmetrical planforms, which heretofore had not been demonstrated.
Journal ArticleDOI
Formulation of a Galerkin spectral element-fourier method for three-dimensional incompressible flows in cylindrical geometries
TL;DR: In this article, a primitive variable formulation for simulation of time-dependent incompressible flows in cylindrical coordinates is developed, where Spectral elements are used to discretise the meridional semi-plane, coupled with Fourier expansions in azimuth.
Journal ArticleDOI
Correlation equations for free convection heat transfer in horizontal layers of air and water
TL;DR: In this paper, the authors reported new experimental measurements on the natural convective heat transport through a horizontal layer of air, covering the Rayleigh number range from subcritical to 4 × 106.