Novel Test Facility for Investigation of the Impact of Thermally Induced Stress Gradients on Fatigue Life of Cooled Gas Turbine Components

2018 ◽  
Vol 141 (3) ◽  
Author(s):  
Marcus Thiele ◽  
Uwe Gampe ◽  
Kathrin A. Fischer
Keyword(s):  
Service Life ◽  
Gas Turbine ◽  
Heat Fluxes ◽  
Temperature Gradients ◽  
Test Facility ◽  
Test Results ◽  
Thermally Induced ◽  
Stress Gradients ◽  
Induced Stress ◽  
The Impact

A novel test facility has been designed and setup for the investigation of the influence of stationary temperature, and thus thermally induced stress gradients with respect to the damage evolution of cooled gas turbine components. Thermally induced stress gradients differ from geometrically induced stress gradients. From the point of view of stress mechanics, they are independent from external loads. From the perspective of material mechanics, their impact on service life is influenced by locally different material properties and strength. However, the impact of thermally induced stress gradients on the cyclic life of high loaded, cooled components is not precisely known. In order to increase knowledge surrounding these mechanisms, a research project was launched. To achieve high temperature gradients and extended mechanical stress gradients, large heat fluxes are required. The authors developed a test bench with a unique radiant heating to achieve very high heat fluxes of q˙ ≥ 1.6 MW/m2 on cylindrical specimen. Special emphasis has been placed on homogenous temperature and loading conditions in order to achieve valid test results comparable to standard low-cycle or thermo-mechanical fatigue tests. Different test concepts of the literature were reviewed and the superior performance of the new test rig concept was demonstrated. The austenitic stainless steel 316 L was chosen as the model material for commissioning and validation of the test facility. The investigation of thermally induced stress gradients and, based on this analysis, low-cycle fatigue (LCF) tests with superimposed temperature gradients were conducted. Linear elastic finite element studies were performed to calculate the local stress–strain field and the service life of the test specimens. The test results show a considerable influence of the temperature gradient on the LCF life of the investigated material. Both the temperature variation over the specimen wall and thermally induced stresses (TIS) are stated to be the main drivers for the change in LCF life. The test results increase the understanding of fatigue damage mechanisms under local unsteady conditions and can serve as a basis for improved lifetime calculation methods.

Novel Test Facility for Investigation of the Impact of Thermally Induced Stress Gradients on Fatigue Life of Cooled Gas Turbine Components

2018 ◽  
Author(s):  
Marcus Thiele ◽  
Uwe Gampe ◽  
Kathrin A. Fischer
Keyword(s):  
Fatigue Life ◽  
Low Cycle Fatigue ◽  
Heat Fluxes ◽  
Test Facility ◽  
Test Results ◽  
Cycle Fatigue ◽  
Thermally Induced ◽  
Stress Gradients ◽  
Induced Stress ◽  
The Impact

A novel test facility has been designed and set up for the investigation of the influence of stationary temperature, and thus thermally induced stress gradients with respect to the damage evolution of cooled gas turbine components. Thermally induced stress gradients differ from geometrically induced stress gradients. From the point of view of stress mechanics, they are independent from external loads. From the perspective of material mechanics, their impact on service life is influenced by locally different material properties and strength. However, the impact of thermally induced stress gradients on the cyclic life of high loaded, cooled components is not precisely known. In order to increase knowledge surrounding these mechanisms, a research project was launched. To achieve high temperature gradients and extended mechanical stress gradients, large heat fluxes are required. The authors developed a test bench with a unique radiant heating to achieve very high heat fluxes of q̇ ≥ 1.6MW/m2 on cylindrical specimen. Special emphasis has been placed on homogenous temperature and loading conditions in order to achieve valid test results comparable to standard low cycle or thermo-mechanical fatigue tests. Different test concepts of the literature were reviewed and the superior performance of the new test rig concept was demonstrated. The austenitic stainless steel 316L was chosen as the model material for commissioning and validation of the test facility. The investigation of thermally induced stress gradients and, based on this analysis, low-cycle fatigue tests with superimposed temperature gradients were conducted. Linear elastic finite element studies were performed to calculate the local stress-strain field and the service life of the test specimens. The test results show a considerable influence of the temperature gradient on the low-cycle fatigue life of the investigated material. Both the temperature variation over the specimen wall and thermally induced stresses are stated to be the main drivers for the change in low-cycle fatigue life. The test results increase the understanding of fatigue damage mechanisms under local unsteady conditions and can serve as a basis for improved lifetime calculation methods.

Experimental and Numerical Investigation on the Influence of Thermally Induced Stress Gradients on Fatigue Life of the Nickel-Base Alloy Mar-M247

2019 ◽  
Author(s):  
Marcus Thiele ◽  
Stefan Eckmann ◽  
Min Huang ◽  
Uwe Gampe ◽  
Kathrin A. Fischer ◽  
...  
Keyword(s):  
High Temperature ◽  
Fatigue Life ◽  
Base Alloy ◽  
Low Cycle Fatigue ◽  
Heat Fluxes ◽  
Cycle Fatigue ◽  
Thermally Induced ◽  
Stress Gradients ◽  
Induced Stress ◽  
Nickel Base

Abstract Today’s and future parameters of stationary gas turbines and aircraft engines require intensive and highly efficient cooling of hot gas path components. High temperature and thermally induced stress gradients with impact on fatigue life are the consequence. Thermally induced stress gradients differ from geometrically induced stress gradients with respect to stress mechanics by the independence from external loads and material mechanics by the influence of temperature on material properties and strength. Regarding the contribution and evaluation on damage, the latter characteristic feature in turbomachinery is currently not fully understood. Therefore, a test facility has been designed, set up, and reported in GT2018-76519 for the investigation of the influence of stationary temperature, and thus thermally induced stress gradients, on the damage evolution of cooled high-temperature components. To achieve high temperature and thermally induced stress gradients, large heat fluxes are required. A unique radiation heating has been developed allowing very high heat fluxes of q̇ ≥ 1.5 MW/m2 for testing of hollow cylindrical specimens. The conventional cast nickel-base alloy Mar-M247 has been chosen to study the influence of thermally induced stress gradients on fatigue life. The low-cycle fatigue testing of the hollow cylindrical specimens has been conducted both with and without superimposed stationary temperature gradients. In addition, Complex Low-Cycle Fatigue (CLCF) tests with symmetric and nonsymmetric loading conditions have been performed to provide the necessary database for the adaptation of a viscoplastic deformation model. To calculate the local stress-strain field and service life of the test specimens, linear elastic and viscoplastic finite element studies have been performed and were assessed by means of a fracture mechanics-based lifetime model. The test results show the considerable influence of the temperature gradient on the low-cycle fatigue life for the investigated material. Both the radial temperature variation over the specimen wall with a hot outer surface and a cooled inner surface as well as the thermally induced stresses are stated to be the main drivers for the change in low-cycle fatigue life. The test results enhance the understanding of fatigue-damage mechanisms under local unsteady conditions and can be used as a basis for improved service life predictions.

Experimental and Numerical Investigation on the Influence of Thermally Induced Stress Gradients on Fatigue Life of the Nickel-Base Alloy Mar-M247

2020 ◽  
Vol 142 (10) ◽  
Author(s):  
Marcus Thiele ◽  
Stefan Eckmann ◽  
Min Huang ◽  
Uwe Gampe ◽  
Kathrin A. Fischer ◽  
...  
Keyword(s):  
High Temperature ◽  
Fatigue Life ◽  
Base Alloy ◽  
Low Cycle Fatigue ◽  
Heat Fluxes ◽  
Cycle Fatigue ◽  
Thermally Induced ◽  
Stress Gradients ◽  
Induced Stress ◽  
Nickel Base

Abstract Today's and future parameters of stationary gas turbines and aircraft engines require intensive and highly efficient cooling of hot gas path components. High temperature and thermally induced stress gradients with impact on fatigue life are the consequence. Thermally induced stress gradients differ from geometrically induced stress gradients with respect to stress mechanics by the independence from external loads and material mechanics by the influence of temperature on material properties and strength. Regarding the contribution and evaluation on damage, the latter characteristic feature in turbomachinery is currently not fully understood. Therefore, a test facility has been designed, setup, and reported in GTP-18-1482 for the investigation of the influence of stationary temperature, and thus thermally induced stress gradients, on the damage evolution of cooled high-temperature components. To achieve high temperature and thermally induced stress gradients, large heat fluxes are required. A unique radiation heating has been developed allowing very high heat fluxes of q˙ ≥ 1.5 MW/m2 for testing of hollow cylindrical specimens. The conventional cast nickel-base alloy Mar-M247 has been chosen to study the influence of thermally induced stress gradients on fatigue life. The low-cycle fatigue testing of the hollow cylindrical specimens has been conducted both with and without superimposed stationary temperature gradients. In addition, complex low-cycle fatigue (CLCF) tests with symmetric and nonsymmetric loading conditions have been performed to provide the necessary database for the adaptation of a viscoplastic deformation model. To calculate the local stress–strain field and service life of the test specimens, linear elastic and viscoplastic finite element studies have been performed and were assessed by means of a fracture mechanics-based lifetime model. The test results show the considerable influence of the temperature gradient on the low-cycle fatigue life for the investigated material. Both the radial temperature variation over the specimen wall with a hot outer surface and a cooled inner surface as well as the thermally induced stresses are stated to be the main drivers for the change in low-cycle fatigue life. The test results enhance the understanding of fatigue-damage mechanisms under local unsteady conditions and can be used as a basis for improved service life predictions.

scholarly journals Field Experience of the Sequential Combustion System for the GT24/GT26 Gas Turbine Family

1998 ◽  
Author(s):  
Franz Joos ◽  
Philipp Brunner ◽  
Marcel Stalder ◽  
Stefan Tschirren
Keyword(s):  
Gas Turbine ◽  
Research Work ◽  
Basic Research ◽  
Test Facility ◽  
Test Results ◽  
Combustion System ◽  
System A ◽  
Commercial Operation ◽  
Near Future

The first units of the Sequential Combustion System gas turbine family are in commercial operation. The first gas turbine GT24 (60Hz, 165MW-class) started the commercial operation, while the first GT26 (50Hz, 265MW-class) demonstrates its performance at the GT test facility. More engines are presently in the commissioning phase or will be in the near future. These turbines are designed to offer increased output at high GT efficiency. To acheive this, the sequential combustion system, a reheat process with two combustors, has been developed. Whereas the first combustor is based on the proven EV-combustor technology, extensive research and development efforts have been carried out in developing the lean premixed self-igniting second combustor (SEV). This paper is a follow-up of the ASME paper 96-GT-315, which described the basic research work concerning the lean premixing SEV-burners with self-ignition. The present paper reports the experience gained during commissioning of the first engines. The performance of the two combustors, as well as the measured emissions, are discussed and compared with the expected values and rig test results. Finally, the potential of the sequential combustion system to reach low NOx levels is demonstrated by unveiling the results of the extensive testing program during the commissioning phase.

scholarly journals A Unique Small Gas Turbine Test Facility for Low-Cost Investigations of Ceramic Rotor Materials and Thermal Barrier Coatings

1998 ◽  
Author(s):  
Björn Schenk ◽  
Torsten Eggert ◽  
Helmut Pucher
Keyword(s):  
Combustion Chamber ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Low Cost ◽  
Temperature Gradients ◽  
Test Facility ◽  
Small Scale ◽  
Transient Temperature ◽  
Turbine Inlet ◽  
Turbine Rotors

The paper describes a test facility for small-scale gas turbines, which basically has been designed and assembled at the Institute of Combustion Engines of the Technical University Berlin. The facility exposes ceramic rotor components to the most significant loads that occur during real gas turbine operation in a clearly predefined manner (high circumferential velocities and highest turbine inlet temperatures). The test facility allows the investigation of bladed radial inflow turbine rotors, as well as — in a preceding step — geometrically simplified ceramic or coated metallic rotors. A newly designed, ceramically lined, variable geometry combustion chamber allows turbine inlet temperatures up to 1450°C (2640 F). A fast thermal shock unit (switching time of about 1s), which is integrated into the test facility between the combustion chamber and the turbine scroll, can be used to create, for example, severe transient temperature gradients within the rotor components to simulate gas turbine trip conditions. In order to generate steady state temperature gradients, especially during disk testing, the rotor components can be subjected to an impingement cooling of the rotor back face (uncoated in case of TBC-testing). The test facility is additionally equipped with a non-contact transient temperature measurement system (turbine radiation pyrometry) to determine the test rotor surface temperature distribution during operation. Apart from the possibilities of basic rotor material investigations, the test facility can also be used to automatically generate compressor and turbine performance characteristics maps. The latter might be used to assess the aerodynamic performance of bladed ceramic radial inflow or mixed flow turbine rotors with respect to manufacturing tolerances due to near-net-shape forming processes (e.g., gelcasting or injection molding).

Initial Operating Experience and Test Results of ABB’s Gas Turbine GT13E2

1995 ◽  
Author(s):  
M. Klohr ◽  
J. Schmidtke ◽  
S. Tschirren ◽  
P. Rihak
Keyword(s):  
Gas Turbine ◽  
Dynamic Pressure ◽  
Operating Experience ◽  
Combined Cycle ◽  
Test Facility ◽  
Vibration Velocity ◽  
Inlet Temperature ◽  
Test Results ◽  
Pressure System ◽  
Annular Combustor

On 20 October 1993, the first ABB GT13E2 gas turbine was put into operation. This 165 MW class gas turbine achieves 35,7% thermal efficiency in single cycle application and up to 54,3% (according ISO standard 3977, Annexe F) in a three pressure system. An optimised turbine and compressor design along with the increased turbine inlet temperature, lead to improved efficiency and electrical output. A new concept for the combustor aimed at meeting the increasing demands on gas turbine emissions. The GT13E2 is equipped with the new single annular combustor and 72 of the ABB EV double cone burners. The commissioning and testing of the first GT13E2 was carried out at the Kawasaki Gas Turbine Research Center (KGRC) in Sodegaura City near Tokyo, Japan. The gas turbine was assembled with various measurement systems to monitor static and dynamic pressure, gas and metal temperature, expansion, vibration, velocity and emissions. The facility will be used during a 15 year joint test program by ABB and Kawasaki Heavy Industries (KHI) to obtain a sound database of operating experience for further improvements of the GT13E2 gas turbine. Therefore, mid 1994 a second test phase was conducted and early 1995 a third test period is scheduled. In parallel, the 2nd and 3rd GT13E2’s were commissioned and tested at the Deeside Combined Cycle Power Plant near Chester, Great Britain. In November 1994, the 4th GT13E2 at Lage Weide was successfully commissioned. This paper describes the operating experience with the GT13E2 during the first commissioning and test phases at KGRC and Deeside. The design features, the test facility, the instrumentation, the commissioning and test results are presented and discussed.

Test Results of 40MW-Class Advanced Humid Air Turbine and Exhaust Gas Water Recovery System

2014 ◽  
Author(s):  
Takuya Takeda ◽  
Hidefumi Araki ◽  
Yasushi Iwai ◽  
Tetsuro Morisaki ◽  
Kazuhiko Sato
Keyword(s):  
Gas Turbine ◽  
Test Facility ◽  
Nox Emissions ◽  
Exhaust Gas ◽  
Water Recovery ◽  
Test Results ◽  
Operational Flexibility ◽  
Start Up ◽  
Air Turbine ◽  
Recovery System

Operational flexibility, such as faster start-up time or faster load change rate, and higher thermal efficiency, have become more and more important for recent thermal power systems. The advanced humid air turbine (AHAT) system has been studied to improve operational flexibility and thermal efficiency of gas turbine power generation systems. A 40MW-class AHAT test facility was built and the rated output was achieved. Through operations at the facility, it has been verified for the first time that the key components of the medium-class gas turbines, such as an axial compressor and multi-can combustor, can be applied to the AHAT system. The cold start-up time from ignition to rated power was about 60 min, which is approximately one-third that of a conventional gas turbine combined cycle (GTCC) plant. NOx emissions were 24ppm (at 16% O2) when the humidity of combustion air was approximately a half that of present commercial AHAT plants, and NOx emissions in a future commercial AHAT system were thought to be less than 10ppm. A water recovery system which recovers water from a part of the exhaust gas of the 40MW-class test facility was built and test operations were made from June 2013. In this paper, water recovery test results as well as the 40MW-class gas turbine test results are shown.

Advanced Burner Development for the Vx4.3A Gas Turbines

2001 ◽  
Author(s):  
Holger Streb ◽  
Bernd Prade ◽  
Thomas Hahner ◽  
Stefan Hoffmann
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Field Evaluation ◽  
Test Facility ◽  
Nox Emissions ◽  
Exhaust Gas ◽  
Test Results ◽  
Exhaust Gas Emission ◽  
Annular Combustor ◽  
Base Load

The Vx4.3A gas turbine family has already been well received by the market. Nevertheless the market drives technology towards both increased turbine inlet temperatures and reduced emissions. The HR3 burner was originally developed for the V4.2 and Vx4.3 fleet featuring silo combustors in order to mitigate the risk of flashback and to improve the NOx- emissions (Prade, Streb, 1996). Due to its favourable performance characteristics in the Vx4.3 family the advanced HR3 burner was adapted to the Vx4.3A series with annular combustor. The paper reports upon the design, testing and field evaluation steps which were necessary to implement the burner for the 50 and 60 cycle gas turbines. With CFD calculations the flow field and the mixing of natural gas and combustion air have been optimised. A number of tests in the Siemens test facilities confirmed these predictions. The atmospheric 3 burner segment combustion test rig allows to test flame interaction, stability and exhaust gas emission simultaneously. In the Siemens Berlin Test Facility which provides a platform for full scale gas turbine testing 24 HR3-burners were implemented into a V84.3A gas turbine with a base load power output of 184 MW at ISO conditions for prototype testing before introducing this new burner generation into the bigger 50 cycle family V94.3A. Implementation of 24 scaled HR3 burners were installed in the V94.3A of Cottam Development Centre (Great Britain) and demonstrated an excellent performance. The gas turbine reached an ISO base load output of 265 MW with NOx emissions well below 25 ppmvd. Due to the very promising test results in Berlin and Cottam, this burner modification, which can be retrofitted to all VX4.3A gas turbines, was implemented nearly fleet wide.

scholarly journals Calculations of Heat Transfer in Combustion Chambers of Gas Turbine Plants According to the Laws of Thermal Radiation of Gas volumes

2020 ◽  
Vol 3 (1) ◽  
Keyword(s):  
Heat Transfer ◽  
Service Life ◽  
Thermal Radiation ◽  
Gas Turbine ◽  
Calculation Method ◽  
Scientific Discovery ◽  
High Accuracy ◽  
Heat Fluxes ◽  
Combustion Chambers ◽  
Accurate Picture

The analysis of methods for calculating heat transfer in the combustion chambers of gas turbine plants is carried out. None of the existing methods for calculating heat transfer gives a complete and accurate picture of heat transfer in combustion chambers. The calculation method developed on the basis of scientific discovery allows one to calculate with high accuracy the density of the torch heat fluxes along the surfaces of the flame tube, organize rational heat transfer in the combustion chamber, reduce costs and time of creation of combustion chambers and increase their service life.

scholarly journals Fully Loaded Factory Test of the CW251B12 Gas Turbine Engine

1990 ◽  
Author(s):  
Ihor S. Diakunchak
Keyword(s):  
Gas Turbine ◽  
Test Data ◽  
Performance Test ◽  
Engine Performance ◽  
Test Facility ◽  
Test Results ◽  
Turbine Engine ◽  
Engine Model ◽  
Factory Test ◽  
Industrial Gas Turbine

The fully loaded factory test of the CW251B12 45 MW class industrial gas turbine is described in this paper. This gas turbine is the latest uprating of the W251 series of engines. The main objectives of the factory test were the verification of the performance and the mechanical integrity of the new engine model. A brief description of the main features of the engine, the application of the first unit, the test facility, and the engine instrumentation used in the test is included. Details of the engine performance test results, telemetry test data results, and the hot end component metal temperature measurements are provided.

Sign in / Sign up

Export Citation Format

Share Document