Development of Pyro Igniter for Gas Turbine Engine Application

ASME 2013 Gas Turbine India Conference ◽

10.1115/gtindia2013-3517 ◽

2013 ◽

Author(s):

K. Jayaraman

Keyword(s):

Burning Rate ◽

Gas Turbine ◽

Mechanical Energy ◽

Average Energy ◽

Initial Pressure ◽

Chemical Energy ◽

Gas Turbine Combustor ◽

Composite Propellant ◽

Spark Plug ◽

The Impact

As the initiation of ignition of gas turbine combustor is relying on conventional spark plug methods, it has some limitations at fuel lean mixture conditions, turbulence streams and high altitude relight conditions. Severely reduced spark plug performance and durability is an unfortunate consequence as engines are simultaneously being pushed to higher power densities and leaner stoichiometry in order to improve efficiency and lower emissions. However, an important parameter is the ignition under extreme conditions, lean combustible mixture and high initial pressure, requiring high voltage when using conventional spark plug technology and also significantly reduces the lifetime. An alternative solution to standard spark plug is the use of pyro materials to igniter applications. The overall energy conversion efficiency from chemical energy to electrical energy and mechanical energy will be less when compared to direct conversion of chemical energy to the required applications. Also, the pyro type sources are compact in size. In the gas turbine the exploitation of pyro igniter is inevitable. This research paper involves the demonstration of chlorine free propellant formulation, burning rate studies, application and compatibility of pyro igniter to initiate the ignition of gas turbine combustor. Ammonium Nitrate (AN) plus polymer binder (Hydroxyl Terminated Poly Butadiene – HTPB) and Ammonium Dichromate (ADC) catalyst based composite propellant pyro igniter material have been considered. This composite propellant delivers comparatively low performance, low temperature and low burn rate when compared to Ammonium Perchlorate (AP) based propellant. But AP based propellants discharges corrosive (HCl) gases. AN based composite propellant have chosen for the clean exhaust and non-toxic gases. The impact sensitivity of AN based propellant is quite normal comparable with AP based compositions and low when compared to double based propellants. The burning rate of the propellant is measured in 10 to 60 bar pressure range. The pyro igniter is fabricated and ignition tests are conducted. Average energy release rate of the pyro igniter is 16.6 KJ/s in the designed configuration.

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Gas Turbine Combined Cycle With CO2-Capture Using Auto-Thermal Reforming of Natural Gas

Volume 2: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations ◽

10.1115/2000-gt-0162 ◽

2000 ◽

Cited By ~ 21

Author(s):

Thormod Andersen ◽

Hanne M. Kvamsdal ◽

Olav Bolland

Keyword(s):

Natural Gas ◽

Gas Turbine ◽

Process Integration ◽

Combined Cycle ◽

Co2 Removal ◽

Gas Turbine Combustor ◽

Chemical Absorption ◽

Fuel Gas ◽

The Impact ◽

Water Gas

A concept for capturing and sequestering CO2 from a natural gas fired combined cycle power plant is presented. The present approach is to decarbonise the fuel prior to combustion by reforming natural gas, producing a hydrogen-rich fuel. The reforming process consists of an air-blown pressurised auto-thermal reformer that produces a gas containing H2, CO and a small fraction of CH4 as combustible components. The gas is then led through a water gas shift reactor, where the equilibrium of CO and H2O is shifted towards CO2 and H2. The CO2 is then captured from the resulting gas by chemical absorption. The gas turbine of this system is then fed with a fuel gas containing approximately 50% H2. In order to achieve acceptable level of fuel-to-electricity conversion efficiency, this kind of process is attractive because of the possibility of process integration between the combined cycle and the reforming process. A comparison is made between a “standard” combined cycle and the current process with CO2-removal. This study also comprise an investigation of using a lower pressure level in the reforming section than in the gas turbine combustor and the impact of reduced steam/carbon ratio in the main reformer. The impact on gas turbine operation because of massive air bleed and the use of a hydrogen rich fuel is discussed.

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The Working Principle of a Turbine “Case Study: GE Frame 9E Gas Turbine”

Journal of Engineering Research and Reports ◽

10.9734/jerr/2019/v9i117005 ◽

2019 ◽

pp. 1-20

Author(s):

Obolo Olupitan Emmanuel

Keyword(s):

Internal Combustion Engine ◽

Gas Turbine ◽

Combustion Engine ◽

Mechanical Energy ◽

Internal Combustion ◽

Reciprocating Motion ◽

Fuel Gas ◽

Spark Plug ◽

Working Principle

Gas Turbine is one of the machines that use the thermodynamic principle converting fuel energy to mechanical energy. It is an internal combustion engine. Also, designed to accelerate a stream of gas, which is used to produce a reactive thrust to propel an object or to produce mechanical power that turns a load. It functions in the same way as the internal combustion engine. It sucks in air from the atmosphere, and compress it. The fuel (gas) is injected and ignited (spark plug). The gases expand doing work and finally exhausts outside. Instead of reciprocating motion, the gas turbine uses a rotary motion throughout, and that is the only difference.

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Prediction of Flow and Combustion Characteristics for a Gas Turbine Combustor Burning Low Heating Value Fuel

Volume 2: Combustion, Fuels and Emissions, Parts A and B ◽

10.1115/gt2010-22156 ◽

2010 ◽

Author(s):

M. R. Shaalan ◽

H. A. El Salmawy ◽

M. Anwar Ismail

Keyword(s):

Gas Turbine ◽

Performance Indicators ◽

Substantial Reduction ◽

Combustion Characteristics ◽

Swirl Ratio ◽

Operational Parameters ◽

Gas Turbine Combustor ◽

Heating Value ◽

Secondary Air ◽

The Impact

In this study, a numerical model has been developed to simulate the flow and combustion in a gas turbine combustor of type (Winnox-TUD-Combustor), which burns low heating value gas. The model relies on the computational code “FLUENT”. This code has been used to solve the governing equations. The characteristics of the model are; steady, turbulent, two dimensional, axisymmetric and swirling flow. The combustion process has been simulated as non-premixed combustion. The study includes the impact of several design and operational parameters on the characteristics of the flow and combustion inside the combustion chamber. These parameters include; ratio of secondary to primary air, ratio of tertiary to primary air, swirl ratio, number of inlets of the secondary air and their direction. Four performance indicators have been used to evaluate the impact of the aforementioned design and operating parameters. These indicators include; average temperature of the exhaust gases to the turbine, specific NOx emission, pattern factor and combustion efficiency of the combustor. In order to identify the optimum values of the aforementioned design and operational parameters, Artificial Neural Network (ANN) technique has been utilized to enrich the output results. This facilitates searching for the optimum values of the aforementioned parameters. Furthermore the effect of the variations in fuel composition on the combustion characteristics and accordingly on the performance indicators has been studied. It has been found that, all the studied parameters affect the performance of the combustor to a certain extent. However, fuel swirl ratio, primary to secondary air ratio and tertiary to primary air ratio as well as carbon monoxide to hydrogen ratio in the fuel are the controlling factors. Optimizing these parameters can lead to a substantial reduction in specific NOx emissions down to 4.0 gm/kg of fuel. Also an improvement in pattern factor to values below 0.3 has been achieved.

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Impact of Ethane and Propane Variation in Natural Gas on the Performance of a Model Gas Turbine Combustor

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.1584480 ◽

2003 ◽

Vol 125 (3) ◽

pp. 701-708 ◽

Cited By ~ 21

Author(s):

R. M. Flores ◽

V. G. McDonell ◽

G. S. Samuelsen

Keyword(s):

Natural Gas ◽

Gas Turbine ◽

Statistical Approach ◽

Present System ◽

Fuel Composition ◽

Gas Turbine Combustor ◽

Air Mixing ◽

Gas Fuel ◽

Model Gas Turbine Combustor ◽

The Impact

In the area of stationary power generation, there exists a growing interest in understanding the role that gaseous fuel composition plays on the performance of natural gas-fired gas turbine systems. In this study, an atmospherically fired model gas turbine combustor with a fuel flexible fuel/air premixer is employed to investigate the impact of significant amounts of ethane and propane addition into a baseline natural gas fuel supply. The impacts of these various fuel compositions, in terms of the emissions of NOx and CO, and the coupled impact of the degree of fuel/air mixing, are captured explicitly for the present system by means of a statistically oriented testing methodology. These explicit expressions are also compared to emissions maps that encompass and expand beyond the statistically based test matrix to verify the validity of the employed statistical approach.

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Combustion Dynamics Diagnostics and Mitigation on a Prototype Gas Turbine Combustor

Volume 2: Combustion, Fuels and Emissions, Parts A and B ◽

10.1115/gt2012-68570 ◽

2012 ◽

Author(s):

Bassam S. Mohammad ◽

Preetham Balasubramanyam ◽

Keith McManus ◽

Jeffrey Ruszczyk ◽

Ahmed M. Elkady ◽

...

Keyword(s):

Gas Turbine ◽

Flame Temperature ◽

Operating Conditions ◽

Published Data ◽

Stable Operation ◽

Nox Emissions ◽

Gas Turbine Combustor ◽

Combustion Dynamics ◽

The Impact ◽

Intermittent Mode

Combustion dynamics have detrimental effects on hardware durability as well as combustor performance and emissions. This paper presents a detailed study on the impact of combustion dynamics on NOx and CO emissions generated from a prototype gas turbine combustor operating at a pressure of 180 psia (12.2 bars) with a pre-heat temperature of 720 F (655.3 K) (E-class machine operating conditions). Two unstable modes are discussed. The first is an intermittent mode, at 750 Hz, that emerges at flame temperatures near 2900°F (1866.5 K), resulting in high NOx and CO emissions. With increasing fuel flow, NOx and CO emissions continue to increase until the flame temperature reaches approximately 3250°F (2061 K), at which point the second acoustic mode begins to dominate. Flame images indicate that the intermittent mode is associated with flame motion which induces the high NOx and CO emissions. The second mode is also a 750 Hz, but of constant amplitude (no intermittency). Operation in this second 750 Hz mode results in significantly reduced NOx and CO emissions. At pressures higher than 180 psia (12.2 bars), the intermittent mode intensifies, leading to flashback at flame temperatures above 2850°F (1839 K). In order to mitigate the intermittent mode, a second configuration of the combustor included an exit area restriction. The exit area restriction eliminated the intermittent mode, resulting in stable operation and low emissions over a temperature range of 2700–3200°F (1755–2033 K). A comparison of the NOx emissions, as function of flame temperature, with previous published data for perfectly premixed indicates that, while the low amplitude 750 Hz oscillations have little effect, the intermittent mode significantly increases emissions. Mode shape analysis shows that the 750 Hz instability corresponds to the 1/4 wave axial mode. In the current research a ceramic liner is used while the previous published data was collected with a quartz liner. Typically, quartz is avoided due to reductions in effective flame temperature by radiation losses. Experiments showed that NOx emissions were not affected by the combustor liner type. This agreement between the quartz and ceramic liners data indicates limited effect from the radiation heat losses on NOx emissions.

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Impact of Ethane and Propane Variation in Natural Gas on the Performance of a Model Gas Turbine Combustor

Volume 1: Turbo Expo 2002 ◽

10.1115/gt2002-30080 ◽

2002 ◽

Author(s):

R. M. Flores ◽

V. G. McDonell ◽

G. S. Samuelsen

Keyword(s):

Natural Gas ◽

Gas Turbine ◽

Statistical Approach ◽

Present System ◽

Fuel Composition ◽

Gas Turbine Combustor ◽

Air Mixing ◽

Gas Fuel ◽

Model Gas Turbine Combustor ◽

The Impact

In the area of stationary power generation, there exists a growing interest in understanding the role that gaseous fuel composition plays on the performance of natural gas-fired gas turbine systems. In this study, an atmospherically fired model gas turbine combustor with a fuel flexible fuel/air premixer is employed to investigate the impact of significant amounts of ethane and propane addition into a baseline natural gas fuel supply. The impacts of these various fuel compositions, in terms of the emissions of NOX and CO, and the coupled impact of the degree of fuel/air mixing, are captured explicitly for the present system by means of a statistically oriented testing methodology. These explicit expressions are also compared to emissions maps that encompass and expand beyond the statistically based test matrix to verify the validity of the employed statistical approach.

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