Parallel Implicit Time-Accurate Navier-Stokes Computations Using Coarse Grid Correction

In the last decade, discontinuous Galerkin (DG) methods have been the subject of extensive research efforts because of their excellent performance in the high-order accurate discretization of advection-diffusion problems on general unstructured grids, and are nowadays finding use in several different applications. In this paper, the potential offered by a high-order accurate DG space discretization method with implicit time integration for the solution of the Reynolds-averaged Navier–Stokes equations coupled with the k-ω turbulence model is investigated in the numerical simulation of the turbulent flow through the well-known T106A turbine cascade. The numerical results demonstrate that, by exploiting high order accurate DG schemes, it is possible to compute accurate simulations of this flow on very coarse grids, with both the high-Reynolds and low-Reynolds number versions of the k-ω turbulence model.

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Numerical Modeling of Radiative and Reactive Flow Field Around a Blunt Body at Hypersonic Regimes

2010 14th International Heat Transfer Conference, Volume 5 ◽

10.1115/ihtc14-22028 ◽

2010 ◽

Author(s):

Morteza Rahmanpour ◽

Reza Ebrahimi ◽

Mehrzad Shams

Keyword(s):

Flow Field ◽

Differential Equations ◽

Heat Fluxes ◽

Transitional Flow ◽

Navier Stokes ◽

Implicit Time ◽

Discrete Ordinates ◽

Two Dimensional ◽

Fully Implicit ◽

Time Marching

A numerical method for calculation of strong radiation for two-dimensional reactive air flow field is developed. The governing equations are taken to be two dimensional, compressible Reynolds-average Navier-Stokes and species transport equations. Also, radiation heat flux in energy equation is evaluated using a model of discrete ordinate method. The model used S4 approximation to reduce the governing system of integro-differential equations to coupled set of partial differential equations. A multiband model is used to construct absorption coefficients. Tangent slab approximation is assumed to determine the characteristic parameters needed in the Discrete Ordinates Method. The turbulent diffusion and heat fluxes are modeled by Baldwin and Lomax method. The flow solution is obtained with a fully implicit time marching method. A thermochemical nonequilibrium formulation appropriate to hypersonic transitional flow of air is presented. The method is compared with existing experimental results and good agreement is observed.

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Navier-Stokes Analysis of Unsteady Transonic Flows Through Gas Turbine Cascades With and Without Coolant Ejection

Volume 1: Aircraft Engine; Marine; Turbomachinery; Microturbines and Small Turbomachinery ◽

10.1115/97-gt-479 ◽

1997 ◽

Cited By ~ 4

Author(s):

T. Tanuma ◽

N. Shibukawa ◽

S. Yamamoto

Keyword(s):

Gas Turbine ◽

Stokes Equations ◽

Viscous Flows ◽

Navier Stokes ◽

Implicit Time ◽

Trailing Edge ◽

Navier Stokes Equations ◽

Time Marching ◽

Turbine Cascades ◽

Annular Cascade

An implicit time-marching higher-order accurate finite-difference method for solving the two-dimensional compressible Navier-Stokes equations was applied to the numerical analyses of steady and unsteady, subsonic and transonic viscous flows through gas turbine cascades with trailing edge coolant ejection. Annular cascade tests were carried out to verify the accuracy of the present analysis. The unsteady aerodynamic mechanisms associated with the interaction between the trailing edge vortices and shock waves and the effect of coolant ejection were evaluated with the present analysis.

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