Aerodynamic Performance of a Transonic Turbine Guide Vane With Trailing Edge Coolant Ejection: Part I—Experimental Approach

1996 ◽  
Vol 118 (3) ◽  
pp. 519-528 ◽  
Author(s):  
C. Kapteijn ◽  
J. Amecke ◽  
V. Michelassi
Keyword(s):  
Gas Turbines ◽  
Experimental Approach ◽  
Guide Vane ◽  
Flow Behavior ◽  
Aerodynamic Performance ◽  
Inlet Guide Vane ◽  
Trailing Edge ◽  
Cooling Flow ◽  
Turbine Guide Vane ◽  
Transonic Turbine

Inlet guide vanes (IGV) of high-temperature gas turbines require an effective trailing edge cooling. But this cooling significantly influences the aerodynamic performance caused by the unavoidable thickening of the trailing edge and the interference of the cooling flow with the main flow. As part of a comprehensive research program, an inlet guide vane was designed and manufactured with two different trailing edge shapes. The results from the cascade tests show that the flow behavior upstream of the trailing edge remains unchanged. The homogeneous values downstream show higher turning and higher losses for the cut-back blade, especially in the supersonic range. Additional tests were conducted with carbon dioxide ejection, in order to analyze the mixing process downstream of the cascade.

Aerodynamic Performance of a Transonic Turbine Guide Vane With Trailing Edge Coolant Ejection: Part I — Experimental Approach

1994 ◽  
Author(s):  
Cornelis Kapteijn ◽  
Jochen Amecke ◽  
Vittorio Michelassi
Keyword(s):  
Gas Turbines ◽  
Experimental Approach ◽  
Guide Vane ◽  
Research Programme ◽  
Aerodynamic Performance ◽  
Inlet Guide Vane ◽  
Trailing Edge ◽  
Cooling Flow ◽  
Turbine Guide Vane ◽  
Transonic Turbine

Inlet guide vanes (IGV) of high temperature gas turbines require an effective trailing edge cooling. But this cooling influences significantly the aerodynamic performance caused by the unavoidable thickening of the trailing edge and the interference of the cooling flow with the main flow. As part of a comprehensive research programme an inlet guide vane was designed and manufactured with two different trailing edge shapes. As a general result turns out from the cascade tests, that the flow behaviour upstream of the trailing edge remains unchanged. The homogeneous values downstream show higher turning and higher losses for the cut-back blade, especially in the supersonic range. Additional test were conducted with carbon dioxide ejection, in order to analyse the mixing process downstream of the cascade.

A Conjugate 3-D Flow and Heat Transfer Analysis of a Thermal Barrier Cooled Turbine Guide Vane

1998 ◽  
Author(s):  
Dieter E. Bohn ◽  
Volker J. Becker
Keyword(s):  
Heat Transfer ◽  
Gas Turbines ◽  
Guide Vane ◽  
Suction Side ◽  
Heat Transfer Analysis ◽  
Thermal Barrier ◽  
Trailing Edge ◽  
Flow And Heat Transfer ◽  
Turbine Guide Vane ◽  
Basic Configuration

This paper presents the numerical investigations of the flow and heat transfer of two configurations of a transonic turbine guide vane. The basic configuration is a vane with convection cooling. The second configuration is additionally coated with a thermal barrier consisting of ZrO2. The results are obtained with a conjugate heat transfer and flow computer code that has been developed at the Institute of Steam and Gas Turbines. Measurement data is available for the basic configuration and the computational results are compared to the experimental results. The results show very good agreement between calculated and measured vane surface temperatures. The trailing edge turns out to be subjected to high thermal loads as it is too thin to be cooled effectively. Secondary flow phenomena like the passage vortex and the corner vortex and their impact on the temperature distribution are discussed. The ZrO2 coating is calculated for a thickness of 300μm. The substrate material temperatures are lowered by about 20 K–29 K in the stagnation point area and by about 27 K–43 K in the shock area on the suction side. At the trailing edge, the coating on the suction side and on the pressure side hardly influences the metal temperature.

Aerodynamic Performance of a Transonic Turbine Guide Vane With Trailing Edge Coolant Ejection: Part II — Numerical Approach

1994 ◽  
Author(s):  
V. Michelassi ◽  
F. Martelli ◽  
J. Amecke
Keyword(s):  
Guide Vane ◽  
Simple Procedure ◽  
Numerical Approach ◽  
Marginal Effect ◽  
Grid Refinement ◽  
Trailing Edge ◽  
Experimental Conditions ◽  
Mach Number Distribution ◽  
Turbine Guide Vane ◽  
Transonic Turbine

The effect of coolant ejection from the trailing edge of a turbine blade is studied by means of numerical simulation codes. Two solvers based on explicit and implicit algorithms with and without multigridding are used in connection with H, HOH and HC grid types. A simple procedure to model the coolant jet at the trailing edge of the blade is presented which does not require excessive grid refinement. The features of the different approaches are discussed in terms of isentropic Mach number distribution on the blade, base pressures and wake profiles at various exit Mach numbers and coolant flow rates which match the experimental conditions. The coolant ejection effect on the shock pattern is discussed. The trailing edge ejection is found to have a marginal effect on the wake shape and on the measured and computed base pressures.

scholarly journals Numerical Investigation of a Radially Cooled Turbine Guide Vane Using Air and Steam as a Cooling Medium

Computation ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 63
Author(s):  
Sondre Norheim ◽  
Shokri Amzin
Keyword(s):  
Numerical Model ◽  
Gas Turbines ◽  
Guide Vane ◽  
Axial Direction ◽  
Average Error ◽  
Inlet Temperature ◽  
Average Temperature ◽  
Cooling Medium ◽  
Turbine Guide Vane ◽  
Steam Cooling

Gas turbine performance is closely linked to the turbine inlet temperature, which is limited by the turbine guide vanes ability to withstand the massive thermal loads. Thus, steam cooling has been introduced as an advanced cooling technology to improve the efficiency of modern high-temperature gas turbines. This study compares the cooling performance of compressed air and steam in the renowned radially cooled NASA C3X turbine guide vane, using a numerical model. The conjugate heat transfer (CHT) model is based on the RANS-method, where the shear stress transport (SST) k−ω model is selected to predict the effects of turbulence. The numerical model is validated against experimental pressure and temperature distributions at the external surface of the vane. The results are in good agreement with the experimental data, with an average error of 1.39% and 3.78%, respectively. By comparing the two coolants, steam is confirmed as the superior cooling medium. The disparity between the coolants increases along the axial direction of the vane, and the total volume average temperature difference is 30 K. Further investigations are recommended to deal with the local hot-spots located near the leading- and trailing edge of the vane.

Dynamic Simulation of Full Start-Up Procedure of Heavy Duty Gas Turbines

2001 ◽  
Author(s):  
J. H. Kim ◽  
T. W. Song ◽  
T. S. Kim ◽  
S. T. Ro
Keyword(s):  
Gas Turbines ◽  
Guide Vane ◽  
Inlet Guide Vane ◽  
Stable Operation ◽  
Heavy Duty ◽  
Operating Characteristics ◽  
Fully Implicit ◽  
Start Up ◽  
Full Speed ◽  
Stage Characteristic

A simulation program for transient analysis of the start-up procedure of heavy duty gas turbines for power generation has been constructed. Unsteady one-dimensional conservation equations are used and equation sets are solved numerically using a fully implicit method. A modified stage-stacking method has been adopted to estimate the operation of the compressor. Compressor stages are grouped into three categories (front, middle, rear), to which three different stage characteristic curves are applied in order to consider the different low-speed operating characteristics. Representative start-up sequences were adopted. The dynamic behavior of a representative heavy duty gas turbine was simulated for a full start-up procedure from zero to full speed. Simulated results matched the field data and confirmed unique characteristics such as the self-sustaining and the possibility of rear-stage choking at low speeds. Effects of the estimated schedules on the start-up characteristics were also investigated. Special attention was paid to the effects of modulating the variable inlet guide vane on start-up characteristics, which play a key role in the stable operation of gas turbines.

scholarly journals Numerical and Experimental Analysis of Secondary Flow in Modern State-of-the-Art Low Pressure Guide Vane Rows

1995 ◽  
Author(s):  
Ernst Lindner
Keyword(s):  
Aspect Ratio ◽  
Secondary Flow ◽  
Total Pressure ◽  
Guide Vane ◽  
Numerical Results ◽  
Flow Behaviour ◽  
Inlet Guide Vane ◽  
Streamwise Vorticity ◽  
Pressure Losses ◽  
Turbine Guide Vane

To enhance the performance of the inlet guide vane and the annular duct of a jet engine, a detailed investigation of annular cascades with two different types of turbine guide vane rows is made. The first one is a leaned guide vane with an aspect ratio of two and a half and a transition duct ahead of the vane. To avoid the losses associated to the decelerating transition duct an alternative vane is designed and investigated with the same inlet and exit conditions. In this case the chord of the vane is increased to the effect that the vane begins immediately at the enterance of the diverging annulus and so a continuously accelerated flow is achieved. To maintain a good performance for this configuration a bowed-type vane with an aspect ratio of one is designed. The aim of the investigation is to obtain detailed informations on the secondary flow behaviour with particular regard to the development of the total pressure losses and the streamwise vorticity of the vortices inside and behind the blade rows. In the first step a three-dimensional, structured, explicit finite-volume flow-solver with a k–ε turbulence model is validated against the measurements, which were made in cross-sections behind the blades. Having proved that the numerical results are very close to the experimental ones, the secondary flow behaviour inside and behind the blade rows is analysed in the second step. By calculating the streamwise vorticity from the numerical results the formation of horse-shoe vortex, passage-vortex and the trailing edge vortex shed is investigated. The differences of the vortical motion and the formation of the total pressure losses between the two configurations of turbine guide vane rows are discussed.

scholarly journals The Effect of Ash Deposition on a Transonic Turbine Guide Vane

2019 ◽  
Author(s):  
Yun Zheng ◽  
◽  
Dong Sun ◽  
Hui Yang ◽  
◽  
...  
Keyword(s):  
Guide Vane ◽  
Ash Deposition ◽  
Turbine Guide Vane ◽  
Transonic Turbine

CFD Simulation of the Losses in an Inlet Guide Vane of a Transonic Test Turbine

2004 ◽  
Author(s):  
W. Sanz ◽  
P. Pieringer ◽  
W. Baumgartner ◽  
W. Edelbauer ◽  
C. Pilz ◽  
...  
Keyword(s):  
Total Pressure ◽  
Cfd Simulation ◽  
Guide Vane ◽  
Measurement Data ◽  
Secondary Flows ◽  
Inlet Guide Vane ◽  
Commercial Code ◽  
Turbine Guide Vane ◽  
Gap Height ◽  
Generation Mechanisms

In this work the flow through a pre-swirl turbine guide vane was calculated using two different flow solvers and compared with total pressure measurements in a downstream plane. The flow is transonic and strongly influenced by secondary flows. A special feature of this cascade is that the gap height at the hub is varying. Flow separation and leakage vortex flow dominate the loss generation. The flow is simulated using an in-house CFD code as well as the commercially available code FLUENT. The flow is carefully analysed and the loss generation mechanisms are presented in detail. The comparison with the measured total pressure distribution shows that the overall loss scheme is well predicted by both codes, but there are still large deficiencies in the quantitative results. The commercial code FLUENT is closer to the measurement data. Further investigations are performed to find out the differences between both codes.

Off-design performance improvement of twin-shaft gas turbine by variable geometry turbine and compressor besides fuel control

2019 ◽  
Vol 234 (7) ◽  
pp. 957-980
Author(s):  
Sepehr Sanaye ◽  
Salahadin Hosseini
Keyword(s):  
Life Cycle ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Guide Vane ◽  
Design Parameters ◽  
Inlet Guide Vane ◽  
Inlet Temperature ◽  
Gas Generator ◽  
Turbine Inlet ◽  
Exit Temperature

A novel procedure for finding the optimum values of design parameters of industrial twin-shaft gas turbines at various ambient temperatures is presented here. This paper focuses on being off design due to various ambient temperatures. The gas turbine modeling is performed by applying compressor and turbine characteristic maps and using thermodynamic matching method. The gas turbine power output is selected as an objective function in optimization procedure with genetic algorithm. Design parameters are compressor inlet guide vane angle, turbine exit temperature, and power turbine inlet nozzle guide vane angle. The novel constrains in optimization are compressor surge margin and turbine blade life cycle. A trained neural network is used for life cycle estimation of high pressure (gas generator) turbine blades. Results for optimum values for nozzle guide vane/inlet guide vane (23°/27°–27°/6°) in ambient temperature range of 25–45 ℃ provided higher net power output (3–4.3%) and more secured compressor surge margin in comparison with that for gas turbines control by turbine exit temperature. Gas turbines thermal efficiency also increased from 0.09 to 0.34% (while the gas generator turbine first rotor blade creep life cycle was kept almost constant about 40,000 h). Meanwhile, the averaged values for turbine exit temperature/turbine inlet temperature changed from 831.2/1475 to 823/1471°K, respectively, which shows about 1% decrease in turbine exit temperature and 0.3% decrease in turbine inlet temperature.

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