Direct Measurements of Overall Effectiveness and Heat Flux on a Film Cooled Test Article at High Temperatures and Pressures

The energy requirements associated with recovering greenhouse gases from Integrated Gasification Combined Cycle (IGCC) or Natural Gas Combined Cycle (NGCC) power plants are significant. The subsequent reductions in overall plant efficiency also result in a higher cost of electricity. In order to meet the future demand for cleaner energy production, this research is focused on improving gas turbine efficiency through advancements in gas turbine cooling capabilities. For this study, an experimental approach was developed to quantify overall effectiveness and net heat flux reduction for a film-cooled test article at high temperature and pressure conditions. A major part of this study focused on validating an advanced optical thermography technique capable of distinguishing between emitted and reflected radiation from film-cooled test articles exposed to exhaust gases in excess of 1000°C and 5 bar. The optical thermography method was used to acquire temperature maps of both external and internal wall temperatures on a test article with fan-shaped film cooling holes. The overall effectiveness and heat flux were quantified with one experiment. The optical temperature measurement technique was capable of measuring wall temperatures to within ±7.2°C. Uncertainty estimates showed that the methods developed for this study were capable of quantifying improvements in overall effectiveness necessary to meet DOE program goals. Results showed that overall effectiveness increased with an increase in blowing ratio and a decrease in mainstream gas pressure while heat flux contours indicated consistent trends.

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Turning NGCC Into IGCC: Cycle Retrofitting Issues

ASME 2006 Power Conference ◽

10.1115/power2006-88112 ◽

2006 ◽

Cited By ~ 2

Author(s):

Juan Pablo Gutierrez ◽

Terry B. Sullivan ◽

Gerald J. Feller

Keyword(s):

Natural Gas ◽

Gas Turbines ◽

Power Plants ◽

Combined Cycle ◽

Integrated Gasification Combined Cycle ◽

Water Steam ◽

Power Block ◽

Starting Point ◽

Natural Gas Combined Cycle ◽

Gas Plants

The increase in price of natural gas and the need for a cleaner technology to generate electricity has motivated the power industry to move towards Integrated Gasification Combined Cycle (IGCC) plants. The system uses a low heating value fuel such as coal or biomass that is gasified to produce a mixture of hydrogen and carbon monoxide. The potential for efficiency improvement and the decrease in emissions resulting from this process compared to coal-fired power plants are strong evidence to the argument that IGCC technology will be a key player in the future of power generation. In addition to new IGCC plants, and as a result of new emissions regulations, industry is looking at possibilities for retrofitting existing natural gas plants. This paper studies the feasibility of retrofitting existing gas turbines of Natural Gas Combined Cycle (NGCC) power plants to burn syngas, with a focus on the water/steam cycle design limitations and necessary changes. It shows how the gasification island processes can be treated independently and then integrated with the power block to make retrofitting possible. This paper provides a starting point to incorporate the gasification technology to current natural gas plants with minor redesigns.

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Three-Dimensional CFD Analysis of a Gas Turbine Combustor for Medium/Low Heating Value Syngas Fuel

Volume 4: Heat Transfer, Parts A and B ◽

10.1115/gt2008-50662 ◽

2008 ◽

Cited By ~ 1

Author(s):

Yan Xiong ◽

Lucheng Ji ◽

Zhedian Zhang ◽

Yue Wang ◽

Yunhan Xiao

Keyword(s):

Gas Turbine ◽

Film Cooling ◽

Coal Gasification ◽

Stokes Equations ◽

Three Dimensional ◽

Combined Cycle ◽

Gas Turbine Combustor ◽

Integrated Gasification Combined Cycle ◽

Heating Value ◽

Flamelet Model

Gas turbine is one of the key components for integrated gasification combined cycle (IGCC) system. Combustor of the gas turbine needs to burn medium/low heating value syngas produced by coal gasification. In order to save time and cost during the design and development of a gas turbine combustor for medium/low heating value syngas, computational fluid dynamics (CFD) offers a good mean. In this paper, 3D numerical simulations were carried out on a full scale multi-nozzle gas turbine combustor using commercial CFD software FLUENT. A 72 degrees sector was modeled to minimize the number of cells of the grid. For the fluid flow part, viscous Navier-Stokes equations were solved. The realizable k-ε turbulence model was adopted. Steady laminar flamelet model was used for the reacting system. The interaction between fluid turbulence and combustion chemistry was taken into account by the PDF (probability density function) model. The simulation was performed with two design schemes which are head cooling using film-cooling and impingement cooling. The details of the flow field and temperature distribution inside the two gas turbine combustors obtained could be cited as references for design and retrofit. Similarities were found between the predicted and experimental data of the transition duct exit temperature profile. There is much work yet to be done on modeling validation in the future.

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Development of H2-Rich Syngas Fuelled GT for Future IGCC Power Plants: Establishment of a Baseline

Volume 1: Aircraft Engine; Ceramics; Coal, Biomass and Alternative Fuels; Wind Turbine Technology ◽

10.1115/gt2011-45701 ◽

2011 ◽

Cited By ~ 1

Author(s):

Nikolett Sipo¨cz ◽

Mohammad Mansouri ◽

Peter Breuhaus ◽

Mohsen Assadi

Keyword(s):

Gas Turbine ◽

Power Plants ◽

Intermediate Stage ◽

Combined Cycle ◽

Point Of View ◽

System Level ◽

The European Union ◽

Integrated Gasification Combined Cycle ◽

Fuel Flexibility ◽

Integrated Gasification

As part of the European Union (EU) funded H2-IGCC project this work presents the establishment of a baseline Integrated Gasification Combined Cycle (IGCC) power plant configuration under a new set of boundary conditions such as the combustion of undiluted hydrogen-rich syngas and high fuel flexibility. This means solving the problems with high NOx emitting diffusion burners, as this technology requires the costly dilution of the syngas with high flow rates of N2 and/or H2O. An overall goal of the project is to provide an IGCC configuration with a state-of-the-art (SOA) gas turbine (GT) with minor modifications to the existing SOA GT and with the ability to operate on a variety of fuels (H2-rich, syngas and natural gas) to meet the requirements of a future clean power generation. Therefore a detailed thermodynamic analysis of a SOA IGCC plant based on Shell gasification technology and Siemens/Ansaldo gas turbine with and without CO2 capture is presented. A special emphasis has been dedicated to evaluate at an intermediate stage of the project the GT performance and identify current technical constraints for the realization of the targeted fuel flexibility. The work shows that introduction of the low calorific fuel (H2 rich fuel more than 89 mol% H2) has rather small impact on the gas turbine from the system level study point of view. The study has indicated that the combustion of undiluted syngas has the potential of increasing the overall IGCC efficiency.

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Reheat Air-Brayton Combined Cycle Power Conversion Off-Nominal and Transient Performance

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4026612 ◽

2014 ◽

Vol 136 (7) ◽

Cited By ~ 5

Author(s):

Charalampos Andreades ◽

Lindsay Dempsey ◽

Per F. Peterson

Keyword(s):

Natural Gas ◽

Gas Turbine ◽

Nuclear Power ◽

Power Plants ◽

Power Conversion ◽

Companion Paper ◽

Combined Cycle ◽

Natural Gas Combined Cycle ◽

Reference Design ◽

Molten Fluoride

Because molten fluoride salts can deliver heat at temperatures above 600 °C, they can be used to couple nuclear and concentrating solar power heat sources to reheat air combined cycles (RACC). With the open-air configuration used in RACC power conversion, the ability to also inject natural gas or other fuel to boost power at times of high demand provides the electric grid with contingency and flexible capacity while also increasing revenues for the operator. This combination provides several distinct benefits over conventional stand-alone nuclear power plants and natural gas combined cycle and peaking plants. A companion paper discusses the necessary modifications and issues for coupling an external heat source to a conventional gas turbine and provides two baseline designs (derived from the GE 7FB and Alstom GT24). This paper discusses off-nominal operation, transient response, and start-up and shutdown using the GE 7FB gas turbine as the reference design.

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Investigations of a Syngas-Fired Gas Turbine Model Combustor by Planar Laser Techniques

Volume 1: Combustion and Fuels, Education ◽

10.1115/gt2006-90344 ◽

2006 ◽

Cited By ~ 5

Author(s):

Michael Tsurikov ◽

Wolfgang Meier ◽

Klaus-Peter Geigle

Keyword(s):

Gas Turbine ◽

Gas Turbines ◽

Power Plants ◽

Combined Cycle ◽

Operating Conditions ◽

Integrated Gasification Combined Cycle ◽

Combustion Behavior ◽

Air Temperatures ◽

Planar Laser ◽

Integrated Gasification

In order to investigate the combustion behavior of gas turbine flames fired with low-caloric syngases, a model combustor with good optical access for confined, non-premixed swirl flames was developed. The measuring techniques applied were particle image velocimetry, OH* chemiluminescence detection and laser-induced fluorescence of OH. Two different fuel compositions of H2, CO, N2 and CH4, with similar laminar burning velocities, were chosen. Their combustion behavior was studied at two different pressures, two thermal loads and two combustion air temperatures. The overall lean flames (equivalence ratio 0.5) burned very stably and their shapes and combustion behavior were hardly influenced by the fuel composition or by the different operating conditions. The experimental results constitute a data-base that will be used for the validation of numerical combustion models and form a part of a co-operative EC project aiming at the development of highly efficient gas turbines for IGCC (Integrated Gasification Combined Cycle) power plants.

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Dynamic Analysis of an O2 Separating Membrane Reactor for CO2-Emission Free Power Processes

Heat Transfer, Volume 1 ◽

10.1115/imece2006-14226 ◽

2006 ◽

Author(s):

Faruk Selimovic ◽

Jonas Eborn ◽

Bengt Sunde´n ◽

Hubertus Tummescheit

Keyword(s):

Oxygen Transfer ◽

Power Plants ◽

Transient Behavior ◽

Combined Cycle ◽

Pure Oxygen ◽

Reactor Model ◽

Integrated Gasification Combined Cycle ◽

Surface Exchange ◽

Natural Gas Combined Cycle ◽

Open Standard

The need to reduce CO2 emissions from fossil-fuel based power production creates the need for new power plant solutions where the CO2 is captured and stored or reused. Oxygen Transfer Membrane (OTM) is the key component of oxy-fuel combustion processes as pure oxygen is usually required to process reactions (e.g. Natural Gas Combined cycle NGCC, Pulverised Coal-fired power plants PC-plants, Integrated Gasification Combined Cycle IGCC). The transfer of oxygen across such OTM is limited by a number of processes, such as surface exchange and ambipolar diffusion through mixed-conducting gas separation layer. This paper shows a mathematical model of an oxygen transfer membrane incorporated into OTM reactor (OTM reactor consists of High Temperature Heat Exchanger and OTM), where transient behavior takes place. The modeling of the OTM reactor has been carried out to show the importance of optimizing OTM parameters (temperatures, oxygen partial pressures, oxygen flux) and reactor design that enables a high oxygen transfer for optimum performance of future power cycles with CO2 capture. All modeling work was carried out in the modeling language Modelica, which is an open standard for equation-based, object-oriented modeling of physical systems. The OTM reactor model has been built using the CombiPlant Library, a modeling library for combined cycle power plants which is under development.

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Wild Blue Yonder

Mechanical Engineering ◽

10.1115/1.2006-may-3 ◽

2006 ◽

Vol 128 (05) ◽

pp. 36-39

Author(s):

Lee S. Langston

Keyword(s):

Electric Power ◽

Gas Turbine ◽

Gas Turbines ◽

Power Plants ◽

Nuclear Reactor ◽

Combined Cycle ◽

Department Of Energy ◽

Total Production ◽

Integrated Gasification Combined Cycle ◽

Research And Innovation

This paper focuses on research and innovation in the gas turbine industry. The production of nonaviation gas turbines was $3.6 billion in 1990, only 15% of total production. With improvement in thermal efficiency, increases in unit size, and the building of record breaking combined-cycle electric power plants fueled by cheap natural gas, nonaviation production zoomed to a euphoric high of $25.8 billion in 2001. The US Department of Energy announced last year the award of $130 million for 10 new projects to integrate hydrogen-burning gas turbines and turbine subsystems into integrated gasification combined cycle (IGCC) central power stations. Nuclear generation is also a zero-emissions technology, and Pebble Bed Modular Reactor Ltd, a South African company, is developing a gas turbine-nuclear reactor electric power plant, with participating companies that include Westinghouse, MHI of Japan, Nukem of Germany, and South Africa's Eskom.

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