Prediction of Heat Transfer Distribution Over the Surface of Nonfilm-Cooled Nozzle Guide Vane in a Transonic Annular Cascade

2015 ◽  
Author(s):  
Kasem E. Ragab ◽  
Lamyaa El-Gabry
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Guide Vane ◽  
Three Dimensional ◽  
Cfd Model ◽  
Turbine Efficiency ◽  
Commercial Code ◽  
Key Factor ◽  
Nozzle Guide ◽  
Annular Cascade

Having gas turbine components that can withstand high temperatures is a key factor in improving turbine efficiency; therefore, a deeper understanding of the heat transfer phenomena associated with the flow of hot gases over Nozzle Guide Vanes (NGVs) is crucial for proper vane design and implementation of adequate cooling schemes. In this study, the heat transfer distribution over the surface of a nonfilm-cooled NGV in a transonic annular cascade (Mexit=0.89, Reexit=2.6×106) is investigated numerically using a three-dimensional computational fluid dynamics (CFD) model and compared to results from a 2-D Boundary Layer (BL) code (TEXSTAN). The CFD model has been built and analyzed using a finite volume based commercial code (ANSYS CFX). Although the industrial turbine vane is film cooled, the analysis presented will be for the uncooled vane. In order to validate the CFD model against experimental data, a study is carried out on the NASA C3X vane; a CFD model of the C3X vane was built and several modeling parameters are varied in order to obtain good agreement with the experimental data. In addition, the numerical results are compared to those of other analytical and numerical simulations of the C3X vane. The methods found to yield the best agreement for the C3X are implemented in the modeling of the industrial NGV.

Heat Transfer Analysis of the Surface of a Nozzle Guide Vane in a Transonic Annular Cascade

2018 ◽  
Vol 11 (1) ◽  
Author(s):  
Kasem Eid Ragab ◽  
Lamyaa El-Gabry
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Guide Vane ◽  
Three Dimensional ◽  
Turbulence Models ◽  
Heat Transfer Analysis ◽  
Cfd Models ◽  
Commercial Code ◽  
Nozzle Guide ◽  
Annular Cascade

Abstract In the current study, a numerical analysis was performed for the heat transfer over the surface of nozzle guide vanes (NGVs) using three-dimensional computational fluid dynamics (CFD) models. The investigation has taken place in two stages: the baseline nonfilm-cooled NGV and the film-cooled NGV. A finite volume based commercial code was used to build and analyze the CFD models. The investigated annular cascade has no heat transfer measurements available; hence in order to validate the CFD models against experimental data, two standalone studies were carried out on the NASA C3X vanes, one on the nonfilm-cooled C3X vane and the other on the film-cooled C3X vane. Different modeling parameters were investigated including turbulence models in order to obtain good agreement with the C3X experimental data; the same parameters were used afterward to model the industrial NGVs.

Film Cooling Research on the Endwall of a Turbine Nozzle Guide Vane in a Short Duration Annular Cascade: Part 2—Analysis and Correlation of Results

1992 ◽  
Vol 114 (4) ◽  
pp. 741-746 ◽  
Author(s):  
S. P. Harasgama ◽  
C. D. Burton
Keyword(s):  
Heat Transfer ◽  
Pressure Gradient ◽  
Film Cooling ◽  
Guide Vane ◽  
Three Dimensional ◽  
Companion Paper ◽  
Hole Injection ◽  
Nozzle Guide Vane ◽  
Nozzle Guide ◽  
Annular Cascade

Results have been presented on the heat transfer characteristics of the film cooled endwall (platform) of a turbine nozzle guide vane in an annular cascade at engine representative conditions in a companion paper by Harasgama and Burton (1992). The present paper reports on the analysis of these measurements. The experimental results are well represented by the superposition theory of film cooling. It is shown that high cooling effectiveness can be achieved when the data are corrected for axial pressure gradients. The data are correlated against both the slot-wall jet parameter and the discrete hole injection function for flat-plate, zero pressure gradient cases. The pressure gradient correction brings the present data to within ± 11 percent of the discrete hole correlation. Preliminary predictions of heat transfer reduction have been carried out using the STANCOOL program. These indicate that the code can predict the magnitude of heat transfer reduction correctly, although the absolute values are not in good agreement. This is attributed to the three-dimensional nature of the flow at the endwall.

Conjugate heat transfer analysis of a radially cooled nozzle guide vane in an aero gas turbine engine

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
G. L. Arunkumar ◽  
Balachandra P. Shetty ◽  
R. K. Mishra
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Conjugate Heat Transfer ◽  
Guide Vane ◽  
Three Dimensional ◽  
Computational Method ◽  
Heat Transfer Analysis ◽  
Turbine Engine ◽  
Barrier Coating ◽  
Nozzle Guide

Abstract This paper presents a computational method to investigate cooling performance of NASA-C3X cascade vane coated with thermal barrier coating (TBC), for which experimental data are available. The vane was cooled internally by air flows through radially oriented 10 channels. A three-dimensional conjugate heat transfer simulation has been performed which allows the conduction-convection on metal vane by eliminating need of multiple boundary solutions. The predicted aerodynamic and thermal loads with the effect of turbulent intensity is found to be good agreement with experimental data and inclusion of TBC leads to quantitative reduction in vane metal temperature.

Conjugate heat transfer analysis of a radially cooled nozzle guide vane in an aero gas turbine engine

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
G. L. Arunkumar ◽  
Balachandra P. Shetty ◽  
R. K. Mishra
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Conjugate Heat Transfer ◽  
Guide Vane ◽  
Three Dimensional ◽  
Computational Method ◽  
Heat Transfer Analysis ◽  
Turbine Engine ◽  
Barrier Coating ◽  
Nozzle Guide

AbstractThis paper presents a computational method to investigate cooling performance of NASA-C3X cascade vane coated with thermal barrier coating (TBC), for which experimental data are available. The vane was cooled internally by air flows through radially oriented 10 channels. A three-dimensional conjugate heat transfer simulation has been performed which allows the conduction-convection on metal vane by eliminating need of multiple boundary solutions. The predicted aerodynamic and thermal loads with the effect of turbulent intensity is found to be good agreement with experimental data and inclusion of TBC leads to quantitative reduction in vane metal temperature.

Measurement and Calculation of End Wall Heat Transfer and Aerodynamics on a Nozzle Guide Vane in Annular Cascade

1990 ◽  
Author(s):  
N. W. Harvey ◽  
T. V. Jones
Keyword(s):  
Heat Transfer ◽  
Guide Vane ◽  
Three Dimensional ◽  
Surface Flow ◽  
Wall Heat Transfer ◽  
Transfer Rates ◽  
Nozzle Guide Vane ◽  
Nozzle Guide ◽  
Annular Cascade ◽  
End Wall

Detailed measurements of surface static pressures and heat transfer rates on the aerofoil and hub end wall of an annular nozzle guide vane (in the absence of a downstream rotor) are presented. Heat transfer rates have been measured using thin film gauges in an annular cascade in the Pyestock Isentropic Light Piston Cascade. Test Mach numbers, Reynolds numbers and cascade geometry are fully representative of engine conditions. The results of 3-D calculations of surface Mach number and 2-D calculations of aerofoil heat transfer are presented and compared with the measurements. A new method of calculating end wall heat transfer using the axisymmetric analogue for three-dimensional boundary layers is described in detail. The method uses a 3-D Euler solver to calculate the inviscid surface streamlines along which heat transfer coefficients are calculated. The metric coefficient which describes the lateral convergence or divergence of the streamlines is used to include three-dimensional effects in the calculation. The calculated heat transfer rates compare well with the measured values. Reference is made to surface flow visualization in the interpretation of the results.

scholarly journals Film Cooling Research on the Endwall of a Turbine Nozzle Guide Vane in a Short Duration Annular Cascade: Part 2 — Analysis and Correlation of Results

1991 ◽  
Author(s):  
S. P. Harasgama ◽  
C. D. Burton
Keyword(s):  
Heat Transfer ◽  
Pressure Gradient ◽  
Film Cooling ◽  
Guide Vane ◽  
Three Dimensional ◽  
Companion Paper ◽  
Hole Injection ◽  
Nozzle Guide Vane ◽  
Nozzle Guide ◽  
Annular Cascade

Results have been presented on the heat transfer characteristics of the film cooled endwall (platform) of a turbine nozzle guide vane in an annular cascade at engine representative conditions in a companion paper by Harasgama and Burton (1991). The present paper reports on the analysis of these measurements. The experimental results are well represented by the superposition theory of film cooling. It is shown that high cooling effectiveness can be achieved when the data are corrected for axial pressure gradients. The data are correlated against both the slot-wall jet parameter and the discrete hole injection function for flat-plate, zero pressure gradient cases. The pressure gradient correction brings the present data to within ± 11% of the discrete hole correlation. Preliminary predictions of heat transfer reduction have been carried out using the STANCOOL program. These indicate that the code can predict the magnitude of heat transfer reduction correctly, although the absolute values are not in good agreement. This is attributed to the three-dimensional nature of the flow at the endwall.

Heat Transfer Analysis of the Surface of Nonfilm-Cooled and Film-Cooled Nozzle Guide Vanes in Transonic Annular Cascade

2017 ◽  
Author(s):  
Kasem E. Ragab ◽  
Lamyaa El-Gabry
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Guide Vane ◽  
Heat Transfer Analysis ◽  
Guide Vanes ◽  
Cfd Models ◽  
Nozzle Guide Vane ◽  
Nozzle Guide ◽  
Annular Cascade ◽  
Nozzle Guide Vanes

One of the approaches adopted to improve turbine efficiency and increase power to weight ratio is reducing vane count. In the current study, numerical analysis was performed for the heat transfer over the surface of nozzle guide vanes under the condition of reduced vane count using three dimensional computational fluid dynamics (CFD) models. The investigation has taken place in two stages: the baseline nonfilm-cooled nozzle guide vane, and the film-cooled nozzle guide vane. A finite volume based commercial code (ANSYS CFX 15) was used to build and analyze the CFD models. The investigated annular cascade has no heat transfer measurements available; hence in order to validate the CFD models against experimental data, two standalone studies were carried out on the NASA C3X vanes, one on the nonfilm-cooled C3X vane and the other on the film-cooled C3X vane. Different modelling parameters were investigated including turbulence models in order to obtain good agreement with the C3X experimental data, the same parameters were used afterwards to model the industrial nozzle guide vanes. Three Shear Stress Transport (SST) turbulence model variations were evaluated, the SST with Gamma-Theta transition model was found to yield the best agreement with the experimental results; model capabilities were demonstrated when the laminar to turbulent transition took place.

Film Cooling Research on the Endwall of a Turbine Nozzle Guide Vane in a Short Duration Annular Cascade: Part 1—Experimental Technique and Results

1992 ◽  
Vol 114 (4) ◽  
pp. 734-740 ◽  
Author(s):  
S. P. Harasgama ◽  
C. D. Burton
Keyword(s):  
Heat Transfer ◽  
Film Cooling ◽  
Guide Vane ◽  
Density Ratio ◽  
Suction Side ◽  
Coolant Temperature ◽  
Guide Vanes ◽  
Nozzle Guide ◽  
Annular Cascade ◽  
Nozzle Guide Vanes

Heat transfer and aerodynamic measurements have been made on the endwalls of an annular cascade of turbine nozzle guide vanes in the presence of film cooling. The results indicate that high levels of cooling effectiveness can be achieved on the endwalls of turbine nozzle guide vanes (NGV). The NGV were operated at the correct engine nondimensional conditions of Reynolds number, Mach number, gas-to-wall temperature ratio, and gas-to-coolant density ratio. The results show that the secondary flow and horseshoe vortex act on the coolant, which is convected toward the suction side of the NG V endwall passage. Consequently the coolant does not quite reach the pressure side/casing trailing edge, leading to diminished cooling in this region. Increasing the blowing rate from 0.52 to 1.1 results in significant reductions in heat transfer to the endwall. Similar trends are evident when the coolant temperature is reduced. Measured heat transfer rates indicate that over most of the endwall region the film cooling reduces the Nusselt number by 50 to 75 percent.

scholarly journals Wake Region Measurements of a Highly Three-Dimensional Nozzle Guide Vane Tested at DRA Pyestock Using Particle Image Velocimetry

1994 ◽  
Author(s):  
M. Funes-Gallanzi ◽  
P. J. Bryanston-Cross ◽  
K. S. Chana
Keyword(s):  
Flow Field ◽  
High Speed ◽  
Guide Vane ◽  
Three Dimensional ◽  
Light Sheet ◽  
Test Facility ◽  
Velocity Mapping ◽  
Nozzle Guide Vane ◽  
Nozzle Guide ◽  
Annular Cascade

The quantitative whole field flow visualization technique of PIV has over the last few years been successfully demonstrated for transonic flow applications. A series of such measurements has been made at DRA Pyestock. Several of the development stages critical to a full engine application of the work have now been achieved using the Isentropic Light Piston Cascade (ILPC) test facility operating with high inlet turbulence levels: • A method of seeding the flow with 0.5μm diameter styrene particles has provided an even coverage of the flow field. • A method of projecting a 1 mm thick high power Nd/YAG laser light sheet within the turbine stator cascade. This has enabled a complete instantaneous intra-blade velocity mapping of the flow field to be visualized, by a specially developed diffraction-limited optics arrangement. • Software has been developed to automatically analyze the data. Due to the sparse nature of the data obtained, a spatial approach to the extraction of the velocity vector data was employed. • Finally, a comparison of the experimental results with those obtained from a three-dimensional viscous flow program of Dawes; using the Baldwin-Lomax model for eddy viscosity and assuming fully turbulent flow. The measurements provide an instantaneous quantitative whole field visualization of a high-speed unsteady region of flow in a highly three-dimensional nozzle guide vane; which has been successfully compared with a full viscous calculation. This work represents the first such measurements to be made in a full-size transonic annular cascade at engine representative conditions.

Film Cooling Research on the Endwall of a Turbine Nozzle Guide Vane in a Short Duration Annular Cascade: Part 1 — Experimental Technique and Results

1991 ◽  
Author(s):  
S. P. Harasgama ◽  
C. D. Burton
Keyword(s):  
Heat Transfer ◽  
Film Cooling ◽  
Guide Vane ◽  
Density Ratio ◽  
Suction Side ◽  
Coolant Temperature ◽  
Guide Vanes ◽  
Nozzle Guide ◽  
Annular Cascade ◽  
Nozzle Guide Vanes

Heat transfer and aerodynamic measurements have been made on the endwalls of an annular cascade of turbine nozzle guide vanes in the presence of film cooling. The results indicate that high levels of cooling effectiveness can be achieved on the endwalls of turbine nozzle guide vanes (NGV). The NGV were operated at the correct engine non-dimensional conditions of Reynolds number, Mach number, gas-to-wall temperature ratio and gas-to-coolant density ratio. The results show that the secondary flow and horse-shoe vortex act on the coolant which is converted towards the suction side of the NGV endwall passage. Consequently the coolant does not quite reach the pressure side/casing trailing edge, leading to diminished cooling in this region. Increasing the blowing rate from 0.52 to 1.1 results in significant reductions in heat transfer to the endwall. Similar trends are evident when the coolant temperature is reduced. Measured heat transfer rates indicate that over most of the endwall region the film cooling reduces the Nusselt number by 50% to 75%.

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