Three-Dimensional Gas Turbine Combustor Emissions Modeling

1993 ◽  
Vol 115 (3) ◽  
pp. 603-611 ◽  
Author(s):  
N. K. Rizk ◽  
H. C. Mongia
Keyword(s):  
Three Dimensional ◽  
Kinetic Scheme ◽  
Reaction Rates ◽  
Chemical Kinetic ◽  
Emission Model ◽  
Pollutant Formation ◽  
Emissions Modeling ◽  
Pollutant Concentrations ◽  
Mathematical Expressions ◽  
And Performance

An emission model that combines the analytical capabilities of three-dimensional combustor performance codes with mathematical expressions based on detailed chemical kinetic scheme is formulated. The expressions provide the trends of formation and/or the consumption of Nox, CO, and UHC in various regions of the combustor utilizing the details of the flow and combustion characteristics given by the three-dimensional analysis. By this means, the optimization of the combustor design to minimize pollutant formation and maintain satisfactory stability and performance could be achieved. The developed model was used to calculate the emissions produced by several engine combustors that varied significantly in design and concept, and operated on both conventional and high-density fuels. The calculated emissions agreed well with the measurements. The model also provided insight into the regions in the combustor where excessive emissions were formed, and helped to understand the influence of the combustor details and air admissions arrangement on reaction rates and pollutant concentrations.

Three-Dimensional Gas Turbine Combustor Emissions Modeling

1992 ◽  
Author(s):  
N. K. Rizk ◽  
H. C. Mongia
Keyword(s):  
Three Dimensional ◽  
Kinetic Scheme ◽  
Reaction Rates ◽  
Chemical Kinetic ◽  
Emission Model ◽  
Pollutant Formation ◽  
Emissions Modeling ◽  
Pollutant Concentrations ◽  
Mathematical Expressions ◽  
And Performance

An emission model that combines the analytical capabilities of 3-D combustor performance codes with mathematical expressions based on detailed chemical kinetic scheme is formulated. The expressions provide the trends of formation and/or the consumption of NOx, CO, and UHC in various regions of the combustor utilizing the details of the flow and combustion characteristics given by the 3-D analysis. By this means, the optimization of the combustor design to minimize pollutant formation and maintain satisfactory stability and performance could be achieved. The developed model was used to calculate the emissions produced by several engine combustors that varied significantly in design and concept, and operated on both conventional and high density fuels. The calculated emissions agreed well with the measurements. The model also provided insight into the regions in the combustor where excessive emissions were formed, and helped to understand the influence of the combustor details and air admission arrangement on reaction rates and pollutant concentrations.

A Semi-Analytical Emission Model for Diffusion Flame, Rich/Lean and Premixed Lean Combustors

1995 ◽  
Vol 117 (2) ◽  
pp. 290-301 ◽  
Author(s):  
N. K. Rizk ◽  
H. C. Mongia
Keyword(s):  
Gas Turbine ◽  
Diffusion Flame ◽  
Kinetic Scheme ◽  
Reaction Rates ◽  
Chemical Kinetic ◽  
Operating Conditions ◽  
Development Effort ◽  
Emission Model ◽  
Performance And Emissions ◽  
And Performance

To enhance gas turbine combustor performance and emissions characteristics, better design methods need to be developed. In the present investigation, an emission model that simulates a detailed chemical kinetic scheme has been developed to provide the rate of reactions of the parent fuel, an intermediate hydrocarbon compound, CO, and H2. The intermediate fuel has variable carbon and hydrogen contents depending on operating conditions, that were selected in the development effort to simulate actual operation of rich/lean, diffusion flame, and lean combustor concepts. The developed reaction rate expressions address also the limited reaction rates that may occur in the near-wall regions of the combustor due to the admittance of radial air jets and cooling air in these regions. The validation effort included the application of the developed model to a combustor simulated by a multiple-reactor arrangement. The results indicate the accurate duplication of the calculations obtained from the detailed kinetic scheme using the developed model. This illustrates the great potential of using such a unified approach to guide the design of various types of combustor to meet the more stringent approach to guide the design of various types of combustor to meet the more stringent emissions and performance requirements of next-generation gas turbine engines.

scholarly journals A Semianalytical Emission Model for Diffusion Flame, Rich/Lean, and Premixed Lean Combustors

1993 ◽  
Author(s):  
N. K. Rizk ◽  
H. C. Mongia
Keyword(s):  
Gas Turbine ◽  
Diffusion Flame ◽  
Kinetic Scheme ◽  
Reaction Rates ◽  
Chemical Kinetic ◽  
Operating Conditions ◽  
Development Effort ◽  
Emission Model ◽  
Turbine Engine ◽  
Performance And Emissions

To enhance gas turbine combustor performance and emissions characteristics better design methods need to be developed. In the present investigation, an emission model that simulates a detailed chemical kinetic scheme has been developed to provide the rate of reactions of the parent fuel, an intermediate hydrocarbon compound, CO, and H2. The intermediate fuel has variable carbon and hydrogen contents depending on operating conditions, that were selected in the development effort to simulate actual operation of rich/lean, diffusion flame, and lean combustor concepts. The developed reaction rate expressions address also the limited reaction rates that may occur in the near wall regions of the combustor due to the admittance of radial air jets and cooling air in these regions. The validation effort included the application of the developed model to a combustor simulated by a multiple-reactor arrangement. The results indicate the accurate duplication of the calculations obtained from the detailed kinetic scheme using the developed model. This illustrates the great potential of using such a unified approach to guide the design of various types of combustors to meet the more stringent emissions and performance requirements of next generation gas turbine engine.

scholarly journals Review of effective emissions modeling and computation

2011 ◽  
Vol 4 (3) ◽  
pp. 643-667 ◽  
Author(s):  
R. Paoli ◽  
D. Cariolle ◽  
R. Sausen
Keyword(s):  
Large Scale ◽  
Three Dimensional ◽  
Reaction Rates ◽  
Transport Models ◽  
Global Circulation ◽  
Global Circulation Models ◽  
Emissions Modeling ◽  
Exhaust Plumes ◽  
Physical And Chemical ◽  
Scale Grid

Abstract. An important issue in the evaluation of the environmental impact of emissions from concentrated sources such as transport modes, is to understand how processes occurring at the scales of exhaust plumes can influence the physical and chemical state of the atmosphere at regional and global scales. Indeed, three-dimensional global circulation models or chemistry transport models generally assume that emissions are instantaneously diluted into large-scale grid boxes, which may lead, for example, to overpredict the efficiency of NOx to produce ozone. In recent times, various methods have been developed to incorporate parameterizations of plume processes into global models that are based e.g. on correcting the original emission indexes or on introducing "subgrid" reaction rates in the models. This paper provides a review of the techniques proposed so far in the literature to account for local conversion of emissions in the plume, as well as the implementation of these techniques into atmospheric codes.

scholarly journals Semianalytical Correlations for NOx, CO, and UHC Emissions

1992 ◽  
Author(s):  
N. K. Rizk ◽  
H. C. Mongia
Keyword(s):  
Kinetic Scheme ◽  
Large Data ◽  
Chemical Kinetic ◽  
Reaction Scheme ◽  
Emission Model ◽  
Future Goals ◽  
Unburned Hydrocarbon ◽  
Annular Combustor ◽  
Analytical Approaches ◽  
Detailed Chemical

To meet the future goals of reduced emissions produced by gas turbine combustors, a better understanding of the process of formation of various pollutants is required. Both empirical and analytical approaches are used to provide the exhaust concentrations of pollutants of interest such as NOx, CO, and unburned hydrocarbon with varying degrees of success. In the present investigation, an emission model that simulates the combustor by a number of reactors representing various combustion zones is proposed. A detailed chemical kinetic scheme was used to provide a fundamental basis for the derivation of a number of expressions that simulate the reaction scheme. The model addresses the combined effects of spray evaporation and mixing in the reaction zone. The model validation included the utilization of a large data base obtained for an annular combustor of a modern turbopropulsion engine. In addition to the satisfactory agreement with the measurements, the model provided insight into the regions within the combustor that could be responsible for the excessive formation of emissions. Methods to reduce the emissions may be implemented in light of such information.

Semianalytical Correlations for NOx, CO, and UHC Emissions

1993 ◽  
Vol 115 (3) ◽  
pp. 612-619 ◽  
Author(s):  
N. K. Rizk ◽  
H. C. Mongia
Keyword(s):  
Kinetic Scheme ◽  
Large Data ◽  
Chemical Kinetic ◽  
Reaction Scheme ◽  
Emission Model ◽  
Future Goals ◽  
Unburned Hydrocarbon ◽  
Annular Combustor ◽  
Analytical Approaches ◽  
Detailed Chemical

To meet the future goals of reduced emissions produced by gas turbine combustors, a better understanding of the process of formation of various pollutants is required. Both empirical and analytical approaches are used to provide the exhaust concentrations of pollutants of interest such as NOx, CO, and unburned hydrocarbon with varying degrees of success. In the present investigation, an emission model that simulates the combustor by a number of reactors representing various combustion zones is proposed. A detailed chemical kinetic scheme was used to provide a fundamental basis for the derivation of a number of expressions that simulate the reaction scheme. The model addresses the combined effects of spray evaporation and mixing in the reaction zone. The model validation included the utilization of a large data base obtained for an annular combustor of a modern turbopropulsion engine. In addition to the satisfactory agreement with the measurements, the model provided insight into the regions within the combustor that could be responsible for the excessive formation of emissions. Methods to reduce the emissions may be implemented in light of such information.

The Combustion of Lean Mixtures of Methane and Air—A Kinetic Investigation

1986 ◽  
Vol 108 (4) ◽  
pp. 336-342 ◽  
Author(s):  
M. Hanna ◽  
G. A. Karim
Keyword(s):  
Combustion Process ◽  
Kinetic Scheme ◽  
Reaction Rates ◽  
Chemical Kinetic ◽  
Energy Utilization ◽  
Wide Range ◽  
Lean Mixtures ◽  
The Times ◽  
Combustion Processes ◽  
Detailed Chemical

The combustion of lean mixtures of methane, representing natural gas, in air is examined analytically employing a detailed chemical kinetic scheme involving 14 species and made up of 32 reaction steps that proceed simultaneously. The changes with time in the concentrations of the major relevant reactive species are determined throughout, right from the commencement of the preignition reactions to the time of achieving near equilibrium conditions. The results of such an approach to the combustion process are considered over a wide range of temperature (1200 K–2200 K) and equivalence ratios (from 0.20 to the stoichiometric value). Information is then presented in relation to some important combustion parameters that included the ignition delay, overall reaction rates and the times needed for completing the combustion process. Some guidelines are suggested for effecting eventually improved energy utilization and reduced environmental pollution from combustion processes involving lean mixtures of methane and air.

An Analytical Examination of the Partial Oxidation of Rich Mixtures of Methane and Oxygen

1992 ◽  
Vol 114 (2) ◽  
pp. 152-157 ◽  
Author(s):  
G. A. Karim ◽  
A. S. Hanafi
Keyword(s):  
Partial Oxidation ◽  
Equivalence Ratio ◽  
Kinetic Scheme ◽  
Reaction Rates ◽  
Chemical Kinetic ◽  
Operating Conditions ◽  
Wide Range ◽  
Rich Mixtures ◽  
Detailed Chemical

The uncatalyzed partial oxidation of rich mixtures of methane and oxygen is examined analytically, primarily with the view of hydrogen and/or synthesis gas (hydrogen plus carbon monoxide) production while employing a detailed chemical kinetic scheme of 108 simultaneous reactions and 28 species. The role of various operating conditions in establishing the yield of hydrogen and other products, the corresponding ignition delay periods and reaction rates is examined over a wide range of temperature, equivalence ratio and pressure. Correlations in terms of simple overall Arrhenius expressions are also provided.

Digitalization system of ancient architecture decoration art based on neural network and image features

2020 ◽  
pp. 1-12
Author(s):  
Wu Xin ◽  
Qiu Daping
Keyword(s):  
Neural Network ◽  
Construction Industry ◽  
Three Dimensional ◽  
Performance Testing ◽  
Image Features ◽  
Three Dimensional Model ◽  
Performance Effect ◽  
Data Process ◽  
And Performance ◽  
Construction Mode

The inheritance and innovation of ancient architecture decoration art is an important way for the development of the construction industry. The data process of traditional ancient architecture decoration art is relatively backward, which leads to the obvious distortion of the digitalization of ancient architecture decoration art. In order to improve the digital effect of ancient architecture decoration art, based on neural network, this paper combines the image features to construct a neural network-based ancient architecture decoration art data system model, and graphically expresses the static construction mode and dynamic construction process of the architecture group. Based on this, three-dimensional model reconstruction and scene simulation experiments of architecture groups are realized. In order to verify the performance effect of the system proposed in this paper, it is verified through simulation and performance testing, and data visualization is performed through statistical methods. The result of the study shows that the digitalization effect of the ancient architecture decoration art proposed in this paper is good.

Sea Urchins and Circuses: The Modernist Natural Histories of Jean Painlevé and Alexander Calder

2018 ◽  
Vol 13 (2) ◽  
pp. 187-211
Author(s):  
Patricia E. Chu
Keyword(s):  
New Media ◽  
Sea Urchins ◽  
Life Sciences ◽  
Three Dimensional ◽  
Machine Age ◽  
Avant Garde ◽  
History Of ◽  
And Performance ◽  
The One ◽  
Natural Historian

The Paris avant-garde milieu from which both Cirque Calder/Calder's Circus and Painlevé’s early films emerged was a cultural intersection of art and the twentieth-century life sciences. In turning to the style of current scientific journals, the Paris surrealists can be understood as engaging the (life) sciences not simply as a provider of normative categories of materiality to be dismissed, but as a companion in apprehending the “reality” of a world beneath the surface just as real as the one visible to the naked eye. I will focus in this essay on two modernist practices in new media in the context of the history of the life sciences: Jean Painlevé’s (1902–1989) science films and Alexander Calder's (1898–1976) work in three-dimensional moving art and performance—the Circus. In analyzing Painlevé’s work, I discuss it as exemplary of a moment when life sciences and avant-garde technical methods and philosophies created each other rather than being classified as separate categories of epistemological work. In moving from Painlevé’s films to Alexander Calder's Circus, Painlevé’s cinematography remains at the forefront; I use his film of one of Calder's performances of the Circus, a collaboration the men had taken two decades to complete. Painlevé’s depiction allows us to see the elements of Calder's work that mark it as akin to Painlevé’s own interest in a modern experimental organicism as central to the so-called machine-age. Calder's work can be understood as similarly developing an avant-garde practice along the line between the bestiary of the natural historian and the bestiary of the modern life scientist.

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