95/01724 Fuel NOx formation characteristics and its reduction in gas turbine combustor

Flame interaction between neighboring burners in a gas turbine combustor is investigated numerically for pursuit of its effect on NOx emission from the burners. In a model chamber or liner, EV burners with double cone are installed. Two burners with the same rotating direction of air stream are adopted and the distance between them is variable from 74.2 mm to 222.6 mm by the step size of 37.1 mm. Gaseous methane and air are adopted as fuel and oxidizer, respectively. From steady-state numerical analyses, flow, temperature, and NO concentration fields are calculated in all computational cases to find their correlation with NOx formation. NOx emission is evaluated at the exit of the model chamber with two burners as a function of burner distance and compared with that from a single burner. In all cases of two-burner calculations, NOx emission is higher than that of a single burner, which results from flow interactions between neighboring burners as well as between a burner and a liner wall. NOx emission is affected significantly by flow and flame interactions between them and strongly depends on burner distance. Burner interaction is divided into two regimes of a burner-burner interaction and a burner-wall interaction depending on the distance. In the former regime, NOx emission is reduced as flame interaction between burners is enhanced and in the latter regime, it is also reduced as interaction between the burner and the liner wall is enhanced.

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03/01903 Gas turbine combustor for biomass derived LCV gas, a first approach towards fuel-NOx modeling and experimental validation

Fuel and Energy Abstracts ◽

10.1016/s0140-6701(03)92019-4 ◽

2003 ◽

Vol 44 (5) ◽

pp. 319-320

Keyword(s):

Gas Turbine ◽

Experimental Validation ◽

Gas Turbine Combustor ◽

Fuel Nox

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COMBUSTION AND NOX FORMATION MODELING USING EDDY RESOLVING TURBULENCE MODELS

NONEQUILIBRIUM PROCESSES: RECENT ACCOMPLISHMENTS ◽

10.30826/nepcap9a-37 ◽

2020 ◽

Author(s):

A. M. Sipatov ◽

◽

A. V. Khokhlov ◽

T. V. Abramchuk ◽

R. A. Zagitov ◽

...

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Numerical Methods ◽

Gas Turbine ◽

Turbulence Models ◽

Gas Turbine Combustor ◽

Nox Formation ◽

Engine Design ◽

Computational Fluid Dynamics Cfd ◽

Physical Phenomena

The study of processes occurring in gas turbine combustor is an important part of engine design for achieving the required technical, operational, and environmental characteristics of the engine. During engine design process, both experimental and computational methods are used. The progress in numerical methods of modeling fourdimensional (space and time) physical phenomena and increasing of computation capacity allow application of complex computational fluid dynamics (CFD) methods for simulating such technical devices as the gas turbine combustor.

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A NOx Correlation Method for Gas Turbine Combustors Based on NOx Formation Assumptions

ASME 1974 Winter Annual Meeting: GT Papers ◽

10.1115/74-wa/gt-10 ◽

1974 ◽

Cited By ~ 3

Author(s):

Géza Vermes

Keyword(s):

Gas Turbine ◽

A Priori ◽

Combustion Process ◽

Correlation Method ◽

Inlet Temperature ◽

Nox Emissions ◽

Gas Turbine Combustor ◽

Nox Formation ◽

Simple Method ◽

Fuel Flow

Based on a simplified description of the combustion process in the primary zone of a can type gas turbine combustor, a generalized NOx versus fuel flow relationship is proposed. Using this relationship and considerations based on chemical kinetics, the effect of combustor inlet pressure, inlet temperature and air residence time on NOx formation is investigated in industrial and automotive type combustion chambers. Data reported in the literature and original test work is cited to substantiate the validity of the assumptions. Based on the findings, a simple method is presented to predict NOx emissions of a gas turbine combustor under conditions which differ substantially from those of the test run. The assumptions may be used to assemble a model for a priori prediction of NOx emissions in a given combustion geometry.

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Reaction of Fuel NOx Formation for Gas Turbine Conditions

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2818169 ◽

1998 ◽

Vol 120 (3) ◽

pp. 474-480 ◽

Cited By ~ 5

Author(s):

T. Nakata ◽

M. Sato ◽

T. Hasegawa

Keyword(s):

Gas Turbine ◽

Coal Gasification ◽

Combustion Process ◽

Combined Cycle ◽

Inlet Section ◽

Mixing Condition ◽

Nox Formation ◽

Air Inlet ◽

Secondary Air ◽

Fuel Nox

Ammonia contained in coal-gasified fuel is converted to nitrogen oxides (NOx) in the combustion process of a gas turbine in integrated coal gasification combined cycle (IGCC) system. Research data on fuel-NOx formation are insufficient, and there still remains a wide explored domain. The present research aims at obtaining fundamental knowledge of fuel-NOx formation characteristics by applying reaction kinetics to gas turbine conditions. An instantaneous mixing condition was assumed in the cross section of a gas turbine combustor and both gradual mixing condition and instantaneous mixing condition were assumed at secondary air inlet section. The results may be summarized as follows: (1) in the primary combustion zone under fuel rich condition, HCN and other intermediate products are formed as ammonia contained in the fuel decomposes; (2) formation characteristics of fuel-NOx are affected by the condition of secondary air mixing; and (3) the conversion ratio from ammonia to NOx declines as the pressure inside the combustor rises under the condition of gradual mixing at the secondary air inlet. These results obtained agreed approximately with the experimentation.

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Modelling of NOx Formation of a Premixed DLE Gas Turbine Combustor

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

10.1115/2001-gt-0069 ◽

2001 ◽

Cited By ~ 4

Author(s):

R. L. G. M. Eggels

Keyword(s):

Gas Turbine ◽

Gas Turbines ◽

State Equation ◽

Gas Turbine Combustor ◽

Nox Formation ◽

No Formation ◽

Emission Regulations ◽

Lean Premixed ◽

Industrial Gas Turbines ◽

Two Stages

To comply with the stringent emission regulations industrial gas turbines operate under lean premixed conditions. To be able to predict emissions in an early design phase, advanced premixed combustion models are required. The rate of NOx formation is sensitive to temperature and some radical concentrations, therefore the flame predictions have to be accurate and detailed. It is well known that there are several routes (thermal, prompt, N2O mechanism) by which NOx can be formed. As lean premixed gas turbines operate at relative low flame temperatures, the contribution of the prompt NO and N2O mechanisms has to be accounted for. The modelling of NOx formation is done in a post-processor, as the influence of nitrogen species on the main combustion characteristics is negligible. This post-processor is based on flame calculations using a Flame Generated Manifold method. This is a reduced reaction mechanism, so that only a limited number of variables have to be solved during the CFD computations. A post-processor method has been developed to compute NO formation. Differential equations are solved for NO and N2O, other species including nitrogen are solved using a steady-state equation. The flame and post-processor models are applied to 2-D and 3-D models of an industrial series staged gas turbine. Parameter studies for the fuel split between the two stages and inlet fuel/air ratio variations have been carried out and the data has been compared with generic engine data.

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Catalytic Combustion for Gas Turbine Applications

Volume 1B: Gas Turbines ◽

10.1115/79-gt-188 ◽

1979 ◽

Cited By ~ 3

Author(s):

W. V. Krill ◽

J. P. Kesselring ◽

E. K. Chu

Keyword(s):

Gas Turbine ◽

Catalytic Combustion ◽

Design Criteria ◽

Gas Turbine Combustor ◽

New Concepts ◽

Combustion Technology ◽

Ongoing Development ◽

Model Gas Turbine Combustor ◽

Nox Control ◽

Fuel Nox

Developments in catalytic combustion have shown increasing potential for application in gas turbine combustors. Significant advantages in reducing combustor emissions, particularly nitrogen oxides (NOx), can be realized. Both thermal and fuel NOx control were demonstrated for a developed graded cell catalyst concept. Other criteria for catalyst scaleup and high pressure operation have been developed. The concepts have been demonstrated in a catalytic model gas turbine combustor and a catalytic staged combustor. The staged combustor shows great potential for control of fuel NOx. New concepts in turbine combustors are required to implement catalytic combustion technology. Gas turbine manufacturers were surveyed to identify design criteria. The established criteria were prioritized and incorporated into several conceptual designs for the combustor. Ongoing development will advance the concepts to prototype demonstration.

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