Influence of Leading Edge Fillet and Nonaxisymmetric Contoured Endwall on Turbine NGV Exit Flow Structure and Interactions With the Rim Seal Flow

Turgut, Ozhan; Camcı, Cengiz

doi:10.1115/gt2013-95843

Cited by 11 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Panchal et al [18] found that due to a shift in the secondary flow due to contouring, overall heat transfer was reduced by 15% relative to a flat endwall. More recent work by Schuepbach et al [19], Turgut and Camci [20], and Regina et al [21] have investigated contouring with rim seal purge, and have generally found that contouring is still beneficial at design conditions, although performance can be worsened at off-design conditions.…”

Section: Relevant Past Studiesmentioning

confidence: 99%

Heat Transfer and Film Cooling on a Contoured Blade Endwall With Platform Gap Leakage

Lynch

Thole

2015

Volume 5B: Heat Transfer

View full text Add to dashboard Cite

Turbine blade components in an engine are typically designed with gaps between parts due to manufacturing, assembly, and operational considerations. Coolant is provided to these gaps to limit the ingestion of hot combustion gases. The interaction of the gaps, their leakage flows, and the complex vortical flow at the endwall of a turbine blade can significantly impact endwall heat transfer coefficients and the effectiveness of the leakage flow in providing localized cooling. In particular, a platform gap through the passage, representing the mating interface between adjacent blades in a wheel, has been shown to have a significant effect. Other important turbine blade features present in the engine environment are non-axisymmetric contouring of the endwall, and an upstream rim seal with a gaspath cavity, which can reduce and increase endwall vortical flow, respectively. To understand the platform gap leakage effect in this environment, measurements of endwall heat transfer and film cooling effectiveness were performed in a scaled blade cascade with a non-axisymmetric contour in the passage. A rim seal with a cavity, representing the overlap interface between a stator and rotor, was included upstream of the blades and a nominal purge flowrate of 0.75% of the mainstream was supplied to the rim seal. Results indicated that endwall heat transfer coefficients increased as platform gap net leakage increased from 0% to 0.6% of the mainstream flowrate, but net heat flux to the endwall was reduced due to high cooling effectiveness of the leakage flow.

show abstract

Section: Relevant Past Studiesmentioning

confidence: 99%

Heat Transfer and Film Cooling on a Contoured Blade Endwall With Platform Gap Leakage

Lynch

Thole

2015

Volume 5B: Heat Transfer

View full text Add to dashboard Cite

show abstract

“…Most of the experimental studies of NGV loss in the open literature have been conducted in simplified experiments designed to isolate the impact of particular design features, e.g., film cooling configurations [4][5][6][7]; TE coolant ejection [8][9][10][11]; TE design [12][13][14]; fillets at the vane surface-endwall junctions [15][16][17]; 3D shaping [18][19][20][21][22]; and inlet flow conditions at the combustorturbine interface [23][24][25]. Such experiments are well suited to understanding fundamental aspects of design, but poorly suited to characterizing engine parts in a realistic operating environment.…”

Section: Introductionmentioning

confidence: 99%

Experimental and Numerical Analysis of Loss Characteristics of Cooled Transonic Nozzle Guide Vanes

Burdett

Povey

2022

Journal of Turbomachinery

View full text Add to dashboard Cite

This paper presents high-fidelity experimental traverse measurements downstream of an annular cascade of transonic nozzle guide vanes (NGVs) from a high-pressure (HP) turbine stage. The components are heavily-cooled real engine components from a modern civil gas turbine engine, operated at scaled engine conditions. Tests were conducted in the high technology readiness level (TRL) Engine Component Aerothermal (ECAT) facility at the University of Oxford. High resolution full-area traverse measurements of local kinetic energy (KE) loss coefficient are presented in several axial planes. In particular, we present: circumferential loss coefficient profiles at several radial heights; full-area traverses at three axial planes; and fully mixed-out loss calculations. Analysis of these data gives insight into particular loss structures, overall aerodynamic performance, and wake mixing rates. The effect of exit Mach number on performance is also considered. The data address a gap in the literature for detailed analysis of traverse measurements downstream of HP NGV engine components. Experimental data are compared with steady and unsteady RANS simulations, allowing benchmarking of typical CFD methods for absolute loss prediction of cooled components. There is relatively limited aerodynamic performance data in the literature for heavily cooled NGVs, and this study represents one of the most comprehensive of its type.

show abstract

“…It was found that endwall contouring and LE fillet helps to effectively reduce the horseshoe vortex as well as the secondary flow losses occurring in the turbine passage. 33 Hence it is important to understand that the inclusion of a fillet can give better flow characteristics. Also, the same was not applied yet to BDITs that could lead to futuristic design.…”

Section: Introductionmentioning

confidence: 99%

Effect of fillets on a blade/vane of wave energy harvesting impulse turbine

Maurya¹,

Thandayutham²,

Samad

2022

Proceedings of the Institution of Mechanical Engineers, Part M:

View full text Add to dashboard Cite

Fillets on leading edges (LE) of turbine blades alter flow patterns and change the loss profile. A bidirectional flow impulse turbine utilized for harnessing wave energy is introduced and computational fluid dynamics (CFD) was used to perform various analysis. In the present work, fillets of different radii on the leading and trailing edges of both the rotor blade (RB) and guide vane (GV) are modified to study the change in overall performance. After an appropriate gird convergence study, ANSYS-CFX 16.0 solver is used for solving the Reynolds averaged Navier-Stokes (RANS) equations incorporating the k-ω-SST turbulence closure model. The numerical investigations were performed using the high-resolution scheme with the convergence criteria of 10−6 to produce unwavering results. The results show that the boundary layer near the endwall creates flow blockage and losses. Also, the increase in pressure drop due to the thickening of the boundary layers (BLs) across the blade/vane leads to a depletion in the overall performance of the turbine. The rotor and guide vane filleted turbine experience higher losses than the base model due to the radial pressure gradient that is explained with post-processed figures. The concept of fillet shapes has been applied to gas turbines and which improves the performance of the turbine due to a reduction in the secondary flow losses occurring inside the turbine and the same concept has been applied to wave energy air turbine to check its performance based on the losses present across the turbine passage.

show abstract

Influence of Leading Edge Fillet and Nonaxisymmetric Contoured Endwall on Turbine NGV Exit Flow Structure and Interactions With the Rim Seal Flow

Cited by 11 publications

References 0 publications

Heat Transfer and Film Cooling on a Contoured Blade Endwall With Platform Gap Leakage

Heat Transfer and Film Cooling on a Contoured Blade Endwall With Platform Gap Leakage

Experimental and Numerical Analysis of Loss Characteristics of Cooled Transonic Nozzle Guide Vanes

Effect of fillets on a blade/vane of wave energy harvesting impulse turbine

Contact Info

Product

Resources

About