Calculation of transition in turbine cascades by conditioned Navier-Stokes equations

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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Comparison of Semi-Empirical Correlations and a Navier-Stokes Method for the Overall Performance Assessment of Turbine Cascades

Journal of Fluids Engineering ◽

10.1115/1.1539869 ◽

2003 ◽

Vol 125 (2) ◽

pp. 308-314 ◽

Cited By ~ 2

Author(s):

C. Cravero ◽

A. Satta

Keyword(s):

Stokes Equations ◽

Navier Stokes ◽

Navier Stokes Equations ◽

Flow Angle ◽

Aerodynamic Performances ◽

Outlet Flow ◽

Time Marching ◽

Overall Performance ◽

Turbine Cascades ◽

Semi Empirical

Turbomachinery flows can nowadays be investigated using several numerical techniques to solve the full set of Navier-Stokes equations; nevertheless the accuracy in the computation of losses is still a challenging topic. The paper describes a time-marching method developed by the authors for the integration of the Reynolds averaged Navier-Stokes equations in turbomachinery cascades. The attention is focused on turbine sections and the computed aerodynamic performances (outlet flow angle, profile loss, etc.,) are compared to experimental data and/or correlations. The need for this kind of CFD analysis tools is stressed for the substitution of standard correlations when a new blade is designed.

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Transonic Flow Calculations Through Plane Turbine Cascades Using The Navier-Stokes Equations

Transient/Dynamic Analysis and Constitutive Laws for Engineering Materials ◽

10.1007/978-94-009-3655-3_10 ◽

1987 ◽

pp. 107-113

Author(s):

F. Martelli ◽

A. Boretti

Keyword(s):

Transonic Flow ◽

Stokes Equations ◽

Navier Stokes ◽

Navier Stokes Equations ◽

Turbine Cascades

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Prediction of By-Pass Transition by Means of a Turbulence Weighting Factor: Part II — Application on Turbine Cascades

Volume 3: Heat Transfer; Electric Power; Industrial and Cogeneration ◽

10.1115/99-gt-030 ◽

1999 ◽

Cited By ~ 1

Author(s):

J. Steelant ◽

E. Dick

Keyword(s):

Heat Transfer ◽

Stokes Equations ◽

Transitional Zone ◽

Weighting Factor ◽

Navier Stokes ◽

Intermittent Flow ◽

Turbine Cascade ◽

Navier Stokes Equations ◽

Operational Conditions ◽

Turbine Cascades

To simulate transitional heat transfer experiments in turbine cascades, the conditionally averaged Navier-Stokes equations are used. To cover both the physics of freestream turbulence and the intermittent flow behaviour during transition, a turbulence weighting factor τ is used. A transport equation for this factor, constructed for low Mach number flows, is extended to cope with compressibility. Compressibility in combination with turbulence level and pressure gradient are prime factors for the correct evaluation of the transitional zone. The method is validated on transitional heat transfer measurements in a linear turbine cascade at typical operational conditions.

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Remarks on the asymptotic behaviour of solutions to the compressible Navier–Stokes equations in the half-line

Proceedings of the Royal Society of Edinburgh Section A Mathematics ◽

10.1017/s030821050200032x ◽

2002 ◽

Vol 132 (03) ◽

pp. 627

Keyword(s):

Asymptotic Behaviour ◽

Stokes Equations ◽

Half Line ◽

Navier Stokes ◽

Navier Stokes Equations ◽

Asymptotic Behaviour Of Solutions

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Effects of stator splitter blades on aerodynamic performance of a single-stage transonic axial compressor

JOURNAL OF MECHANICAL ENGINEERING AND SCIENCES ◽

10.15282/jmes.14.4.2020.05.0579 ◽

2020 ◽

Vol 14 (4) ◽

pp. 7369-7378

Author(s):

Ky-Quang Pham ◽

Xuan-Truong Le ◽

Cong-Truong Dinh

Keyword(s):

Stokes Equations ◽

Three Dimensional ◽

Axial Compressor ◽

Aerodynamic Performance ◽

Numerical Results ◽

Single Stage ◽

Navier Stokes ◽

Navier Stokes Equations ◽

Operating Stability ◽

Length Coverage

Splitter blades located between stator blades in a single-stage axial compressor were proposed and investigated in this work to find their effects on aerodynamic performance and operating stability. Aerodynamic performance of the compressor was evaluated using three-dimensional Reynolds-averaged Navier-Stokes equations using the k-e turbulence model with a scalable wall function. The numerical results for the typical performance parameters without stator splitter blades were validated in comparison with experimental data. The numerical results of a parametric study using four geometric parameters (chord length, coverage angle, height and position) of the stator splitter blades showed that the operational stability of the single-stage axial compressor enhances remarkably using the stator splitter blades. The splitters were effective in suppressing flow separation in the stator domain of the compressor at near-stall condition which affects considerably the aerodynamic performance of the compressor.

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