Damage Analysis of Gas Turbine Vanes Using a Thermal Fluid Dynamic and Mechanical Approach

2004 ◽  
Author(s):  
Enrico Marchegiano ◽  
Giancarlo Benelli ◽  
Paolo Gheri ◽  
Donato Aquaro
Keyword(s):  
High Temperature ◽  
Gas Turbine ◽  
Residual Life ◽  
Crack Nucleation ◽  
Fluid Dynamic ◽  
Load Cycle ◽  
Combined Cycle ◽  
Operating Conditions ◽  
Turbine Vanes ◽  
Cycle Systems

Gas turbine combined–cycle systems work with high inlet temperatures, requiring the use of components made of advanced high temperature resistant materials and coatings. These components must be controlled to avoid serious damage to the plants. The durability of these materials and coatings is of great concern to equipment users. This paper deals with a procedure based on thermal fluid dynamic and mechanical integrated analyses of high temperature loaded components. The methodology is applied to uncooled last stator stages vanes of an industrial 165 Mw gas turbine. Several cracks were revealed on these vanes during periodical inspection and mechanical and metallographic investigations were performed. These analyses were used to identify the critical areas of the vanes, from which the component residual life depends on. The procedure was applied to study the damage undergone by gas turbine vanes to discover the causes of crack nucleation and the nucleation mechanism connected to load histories. It has a diagnostic scope, not a predictive one, but it can be considered as the first step of a residual life evaluation and, consequently, of a load cycle optimization: by modifying the future load histories, it could be possible evaluate the best operating conditions to extend component life. The numerical results of these analyses were compared with the damage to vane rows determined during periodical inspections. A good agreement between the analyses results and the inspection data was obtained in terms of critical points and crack locations. The implemented methodology seems to be a powerful tool for increasing the reliability of critical components of gas turbine combined–cycle systems.

Life Management System for Hot-Gas-Path Components of Gas Turbines

1999 ◽  
Author(s):  
Yasushi Hayasaka ◽  
Nobuhiro Isobe ◽  
Shigeo Sakurai ◽  
Kazuhiko Kumata
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Management System ◽  
Residual Life ◽  
Combined Cycle ◽  
Operating Conditions ◽  
Life Assessment ◽  
Hot Gas ◽  
Life Management ◽  
Residual Life Assessment

Recently the number of gas-turbine-powered combined-cycle plants has been increasing because of their efficiency and environmental compatibility. Gas turbine operating conditions are severe, especially for hot-gas-path components. To improve the reliability of such components and to extend their life, we have developed a life management system based on a residual-life-assessment method. The system makes possible integrated residual-life-assessment based on numerical analyses, material destructive-tests, nondestructive inspections, statistical analyses of field machine data, and the use of a database. To develop the system, the primary damage mechanism for each component is clarified and material degradation is evaluated. For nozzles, the system describes a method of predicting the maximum surface crack growth. The validity of the methods is verified by assessment of the inspection data. This paper also describes optimization of operating cost and RAM (reliability, availability and maintainability).

An Air-Brayton Nuclear-Hydrogen Combined-Cycle Peak- and Base-Load Electric Plant

2007 ◽  
Author(s):  
Charles Forsberg
Keyword(s):  
High Temperature ◽  
Power Output ◽  
Nuclear Reactor ◽  
Peak Load ◽  
Combined Cycle ◽  
Operating Conditions ◽  
Electricity Production ◽  
Spinning Reserve ◽  
High Temperature Reactor ◽  
Base Load

A combined-cycle power plant is proposed that uses heat from a high-temperature nuclear reactor and hydrogen produced by the high-temperature reactor to meet base-load and peak-load electrical demands. For base-load electricity production, air is compressed; flows through a heat exchanger, where it is heated to between 700 and 900°C; and exits through a high-temperature gas turbine to produce electricity. The heat, via an intermediate heat-transport loop, is provided by a high-temperature reactor. The hot exhaust from the Brayton-cycle turbine is then fed to a heat recovery steam generator that provides steam to a steam turbine for added electrical power production. To meet peak electricity demand, after nuclear heating of the compressed air, hydrogen is injected into the combustion chamber, combusts, and heats the air to 1300°C—the operating conditions for a standard natural-gas-fired combined-cycle plant. This process increases the plant efficiency and power output. Hydrogen is produced at night by electrolysis or other methods using energy from the nuclear reactor and is stored until needed. Therefore, the electricity output to the electric grid can vary from zero (i.e., when hydrogen is being produced) to the maximum peak power while the nuclear reactor operates at constant load. Because nuclear heat raises air temperatures above the auto-ignition temperatures of the hydrogen and powers the air compressor, the power output can be varied rapidly (compared with the capabilities of fossil-fired turbines) to meet spinning reserve requirements and stabilize the grid.

scholarly journals High-Temperature Turbine Technology Readiness

1982 ◽  
Author(s):  
M. W. Horner ◽  
A. Caruvana
Keyword(s):  
High Temperature ◽  
Gas Turbine ◽  
Phase Ii ◽  
Combined Cycle ◽  
Technology Readiness ◽  
Inlet Temperature ◽  
Test Results ◽  
Turbine Inlet ◽  
Combined Cycle Plant ◽  
Gas Fuel

Final component and technology verification tests have been completed for application to a 2600°F rotor inlet temperature gas turbine. These tests have proven the capability of combustor, turbine hot section, and IGCC fuel systems and controls to operate in a combined cycle plant burning a coal-derived gas fuel at elevated gas turbine inlet temperatures (2600–3000°F). This paper presents recent test results and summarizes the overall progress made during the DOE-HTTT Phase II program.

scholarly journals Thermodynamic analysis of high temperature nuclear reactor coupled with advanced gas turbine combined cycle

2019 ◽  
Vol 23 (Suppl. 4) ◽  
pp. 1187-1197 ◽  
Author(s):  
Marek Jaszczur ◽  
Michal Dudek ◽  
Zygmunt Kolenda
Keyword(s):  
High Temperature ◽  
Power Plant ◽  
Gas Turbine ◽  
Thermodynamic Analysis ◽  
Thermal Efficiency ◽  
Nuclear Power ◽  
Coal Gasification ◽  
Nuclear Reactor ◽  
Combined Cycle ◽  
Oil Processing

One of the most advanced and most effective technology for electricity generation nowadays based on a gas turbine combined cycle. This technology uses natural gas, synthesis gas from the coal gasification or crude oil processing products as the energy carriers but at the same time, gas turbine combined cycle emits SO2, NOx, and CO2 to the environment. In this paper, a thermodynamic analysis of environmentally friendly, high temperature gas nuclear reactor system coupled with gas turbine combined cycle technology has been investigated. The analysed system is one of the most advanced concepts and allows us to produce electricity with the higher thermal efficiency than could be offered by any currently existing nuclear power plant technology. The results show that it is possible to achieve thermal efficiency higher than 50% what is not only more than could be produced by any modern nuclear plant but it is also more than could be offered by traditional (coal or lignite) power plant.

Advancement in Heated Spin Testing Technologies

2013 ◽  
Author(s):  
Hiroaki Endo ◽  
Robert Wetherbee ◽  
Nikhil Kaushal
Keyword(s):  
High Temperature ◽  
Gas Turbine ◽  
Material Properties ◽  
Gas Turbines ◽  
Multiple Scales ◽  
Thermal Conditions ◽  
Complex Stress ◽  
Operating Conditions ◽  
Mechanical Cycling ◽  
Testing Techniques

An ever more rapidly accelerating trend toward pursuing more efficient gas turbines pushes the engines to hotter and more arduous operating conditions. This trend drives the need for new materials, coatings and associated modeling and testing techniques required to evaluate new component design in high temperature environments and complex stress conditions. This paper will present the recent advances in spin testing techniques that are capable of creating complex stress and thermal conditions, which more closely represent “engine like” conditions. The data from the tests will also become essential references that support the effort in Integrated Computational Materials Engineering (ICME) and in the advances in rotor design and lifing analysis models. Future innovation in aerospace products is critically depended on simultaneous engineering of material properties, product design, and manufacturing processes. ICME is an emerging discipline with an approach to design products, the materials that comprise them, and their associated materials processing methods by linking materials models at multiple scales (Structural, Macro, Meso, Micro, Nano, etc). The focus of the ICME is on the materials; understanding how processes produce material structures, how those structures give rise to material properties, and how to select and/or engineer materials for a given application [34]. The use of advanced high temperature spin testing technologies, including thermal gradient and thermo-mechanical cycling capabilities, combined with the innovative use of modern sensors and instrumentation methods, enables the examination of gas turbine discs and blades under the thermal and the mechanical loads that are more relevant to the conditions of the problematic damages occurring in modern gas turbine engines.

scholarly journals Benefits of Solar/Fossil Hybrid Gas Turbine Systems

1979 ◽  
Author(s):  
H. S. Bloomfield
Keyword(s):  
Power Systems ◽  
Gas Turbine ◽  
Combined Cycle ◽  
Brayton Cycle ◽  
Fuel Saving ◽  
Operational Mode ◽  
Fuel Savings ◽  
Cycle Systems ◽  
Potential Benefits ◽  
Near Term

The potential benefits of solar/fossil hybrid gas turbine power systems were assessed. Both retrofit and new systems were considered from the aspects of: cost of electricity, fuel conservation, operational mode, technology requirements, and fuels flexibility. Hybrid retrofit (repowering) of existing combustion (simple Brayton cycle) turbines can provide near-term fuel savings and solar experience, while new and advanced recuperated or combined-cycle systems may be an attractive fuel saving and economically competitive vehicle to transition from today’s gas- and oil-fired powerplants to other more abundant fuels.

A Damage Evaluation Model of Turbine Blade for Gas Turbine

2016 ◽  
Author(s):  
Dengji Zhou ◽  
Meishan Chen ◽  
Huisheng Zhang ◽  
Shilie Weng
Keyword(s):  
High Temperature ◽  
Real Time ◽  
Gas Turbine ◽  
Evaluation Model ◽  
Creep Damage ◽  
Operating Conditions ◽  
Damage Analysis ◽  
Damage Evaluation ◽  
Analysis Model ◽  
Estimation Model

Current maintenance, having a great impact on the safety, reliability and economics of gas turbine, becomes the major obstacle of the application of gas turbine in energy field. An effective solution is to process Condition based Maintenance (CBM) thoroughly for gas turbine. Maintenance of high temperature blade, accounting for most of the maintenance cost and time, is the crucial section of gas turbine maintenance. The suggested life of high temperature blade by Original Equipment Manufacturer (OEM) is based on several certain operating conditions, which is used for Time based Maintenance (TBM). Thus, for the requirement of gas turbine CBM, a damage evaluation model is demanded to estimate the life consumption in real time. A physics-based model is built, consisting of thermodynamic performance simulation model, mechanical stress estimation model, thermal estimation model, creep damage analysis model and fatigue damage analysis model. Unmeasured parameters are simulated by the thermodynamic performance simulation model, as the input of the mechanical stress estimation model and the thermal estimation model. Then the stress and temperature distribution of blades will be got as the input of the creep damage analysis model and the fatigue damage analysis model. The real-time damage of blades will be evaluated based on the creep and fatigue analysis results. To validate this physics-based model, it is used to calculate the lifes of high temperature blade under several certain operating conditions. And the results are compared to the suggestion value of OEM. An application case is designed to evaluate the application effect of this model. The result shows that the relative error of this model is less than 10.4% in selected cases. And it can cut overhaul costs and increase the availability of gas turbine significantly. Therefore, the physical-based damage evaluation model proposed in this paper, is found to be a useful tool to tracing the real-time life consumption of high temperature blade, to support the implementation of CBM for gas turbine, and to guarantee the reliability of gas turbine with lowest maintenance costs.

Development and Testing of Harsh Environment, Wireless Sensor Systems for Industrial Gas Turbines

2009 ◽  
Author(s):  
David Mitchell ◽  
Anand Kulkarni ◽  
Alex Lostetter ◽  
Marcelo Schupbach ◽  
John Fraley ◽  
...  
Keyword(s):  
High Temperature ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Turbine Blades ◽  
Operating Conditions ◽  
Condition Based Maintenance ◽  
Harsh Environment ◽  
Sensor Systems ◽  
Wireless Telemetry ◽  
Industrial Gas Turbines

The potential for savings provided to worldwide operators of industrial gas turbines, by transitioning from the current standard of interval-based maintenance to condition-based maintenance may be in the hundreds of millions of dollars. In addition, the operational flexibility that may be obtained by knowing the historical and current condition of life-limiting components will enable more efficient use of industrial gas turbine resources, with less risk of unplanned outages as a result of off-parameter operations. To date, it has been impossible to apply true condition-based maintenance to industrial gas turbines because the extremely harsh operating conditions in the heart of a gas turbine preclude using the necessary advanced sensor systems to monitor the machine’s condition continuously. Siemens, Rove Technical Services, and Arkansas Power Electronics International are working together to develop a potentially industry-changing technology to build smart, self-aware engine components that incorporate embedded, harsh-environment-capable sensors and high temperature capable wireless telemetry systems for continuously monitoring component condition in the hot gas path turbine sections. The approach involves embedding sensors on complex shapes, such as turbine blades, embedding wireless telemetry systems in regions with temperatures that preclude the use of conventional silicon-based electronics, and successfully transmitting the sensor information from an environment very hostile to wireless signals. The results presented will include those from advanced, harsh environment sensor and wireless telemetry component development activities. In addition, results from laboratory and high temperature rig and spin testing will be discussed.

Gas Turbine Exhaust Expansion Joints, Diverter and Damper Designs for the New Generation of Higher Temperature, High Efficiency Gas Turbines

1989 ◽  
Author(s):  
Lothar Bachmann ◽  
W. Fred Koch
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
High Efficiency ◽  
Combined Cycle ◽  
Operating Conditions ◽  
High Mass ◽  
Expansion Joints ◽  
Gas Turbine Exhaust ◽  
New Generation ◽  
Turbine Exhaust

The purpose of this paper is to update the industry on the evolutionary steps that have been taken to address higher requirements imposed on the new generation combined cycle gas turbine exhaust ducting expansion joints, diverter and damper systems. Since the more challenging applications are in the larger systems, we shall concentrate on sizes from nine (9) square meters up to forty (40) square meters in ducting cross sections. (Reference: General Electric Frame 5 through Frame 9 sizes.) Severe problems encountered in gas turbine applications for the subject equipment are mostly traceable to stress buckling caused by differential expansion of components, improper insulation, unsuitable or incompatible mechanical design of features, components or materials, or poor workmanship. Conventional power plant expansion joints or dampers are designed for entirely different operating conditions and should not be applied in gas turbine applications. The sharp transients during gas turbine start-up as well as the very high temperature and high mass-flow operation conditions require specific designs for gas turbine application.

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