Effects of different preheated CO2/O2 jet in cross-flow on combustion instability and emissions in a lean-premixed combustor

Combustion instability and nitrogen oxides emission are crucial factors for modern gas turbine combustors, which seriously hampers the research and development of advanced combustors. To eliminate combustion instability and NOx emissions simultaneously, effects of the ?Oxy? (CO2/O2, N2/O2, Ar/O2and He/O2) jet in cross flow(JICF)on combustion instability and NOx emissions are experimentally studied. In this research, the flow rate and oxygen ratio of the combustor are varied to evaluate the control effectiveness. Results denotes that all the four oxy fuel gas: CO2/O2, N2/O2, Ar/O2and He/O2, could suppress combustion instability and NOx emissions. The CO2/O2dilution can achieve a better damping results than the other three cases. There are peak values or lowest points of sound pressure amplitude as the parameter of ?Oxy? JICF changes. Mode transition appears in both acoustic signal and CH* chemiluminescence of the flame. But the turning point of mode transition is different. Under the CO2/O2cases, the NOx emission decreases from 22.3ppm to 15.2ppm, the damping ratio of NOxis 40.39%. The flame shape and length were changed under different JICF dilutions. This research could promote the application of jet in cross flow methods on combustion instability or pollutant emissions in gas turbines.

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Numerical study of the velocity field predicted downstream a jet in cross flow using linear and non-linear turbulence models

10.26678/abcm.cobem2019.cob2019-1939 ◽

2019 ◽

Author(s):

Kelvin Cristófalo de Morais ◽

Luis Santos ◽

Claudia Andrade

Keyword(s):

Velocity Field ◽

Numerical Study ◽

Cross Flow ◽

Turbulence Models ◽

Jet In Cross Flow ◽

Non Linear

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Large Eddy Simulation of a Supercritical Fuel Jet in Cross Flow using GPU-Acceleration

54th AIAA Aerospace Sciences Meeting ◽

10.2514/6.2016-1939 ◽

2016 ◽

Cited By ~ 5

Author(s):

Kalyana C. Gottiparthi ◽

Ramanan Sankaran ◽

Anthony M. Ruiz ◽

Guilhem Lacaze ◽

Joseph C. Oefelein

Keyword(s):

Large Eddy Simulation ◽

Cross Flow ◽

Gpu Acceleration ◽

Eddy Simulation ◽

Jet In Cross Flow ◽

Fuel Jet ◽

Large Eddy

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LES of Fuel Jet in Cross-Flow Using Lattice Boltzmann Method

39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit ◽

10.2514/6.2003-5206 ◽

2003 ◽

Cited By ~ 1

Author(s):

Homayoon Feiz ◽

Suresh Menon

Keyword(s):

Lattice Boltzmann Method ◽

Lattice Boltzmann ◽

Cross Flow ◽

Jet In Cross Flow ◽

Fuel Jet ◽

Boltzmann Method

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Extension of the Combustion Stability Range in Dry Low NOx Lean Premixed Gas Turbine Combustor Using a Fuel Rich Annular Pilot Burner

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4026186 ◽

2014 ◽

Vol 136 (5) ◽

Cited By ~ 5

Author(s):

L. Rosentsvit ◽

Y. Levy ◽

V. Erenburg ◽

V. Sherbaum ◽

V. Ovcharenko ◽

...

Keyword(s):

Gas Turbine ◽

Combustion Zone ◽

Combustion Instability ◽

Experimental Results ◽

Nox Emission ◽

Combustion Stability ◽

Stability Range ◽

Numerical Effort ◽

Lean Premixed ◽

Pilot Burner

The present work is concerned with improving combustion stability in lean premixed (LP) gas turbine combustors by injecting free radicals into the combustion zone. The work is a joint experimental and numerical effort aimed at investigating the feasibility of incorporating a circumferential pilot combustor, which operates under rich conditions and directs its radicals enriched exhaust gases into the main combustion zone as the means for stabilization. The investigation includes the development of a chemical reactors network (CRN) model that is based on perfectly stirred reactors modules and on preliminary CFD analysis as well as on testing the method on an experimental model under laboratory conditions. The study is based on the hypothesis that under lean combustion conditions, combustion instability is linked to local extinctions of the flame and consequently, there is a direct correlation between the limiting conditions affecting combustion instability and the lean blowout (LBO) limit of the flame. The experimental results demonstrated the potential reduction of the combustion chamber's LBO limit while maintaining overall NOx emission concentration values within the typical range of low NOx burners and its delicate dependence on the equivalence ratio of the ring pilot flame. A similar result was revealed through the developed CHEMKIN-PRO CRN model that was applied to find the LBO limits of the combined pilot burner and main combustor system, while monitoring the associated emissions. Hence, both the CRN model, and the experimental results, indicate that the radicals enriched ring jet is effective at stabilizing the LP flame, while keeping the NOx emission level within the characteristic range of low NOx combustors.

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The Histogram of Pressure Oscillations Amplitudes, in Lean Premixed Combustions, Caused by Thermo-Acoustic Instabilities

ASME 2010 3rd Joint US-European Fluids Engineering Summer Meeting: Volume 1, Symposia – Parts A, B, and C ◽

10.1115/fedsm-icnmm2010-31102 ◽

2010 ◽

Author(s):

Nasser Seraj Mehdizadeh ◽

Nozar Akbari

Keyword(s):

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Equivalence Ratio ◽

Combustion Instability ◽

Premixed Combustion ◽

Space Distribution ◽

Rayleigh Criterion ◽

Pressure Oscillations ◽

Lean Premixed

Lean premixed combustion is widely used in recent years as a method to achieve the environmental standards with regard to NOx emission. In spite of the mentioned advantage, premixed combustion systems, with equivalence ratios less than one, are susceptible to the combustion instability. To study the lean combustion instability, by experiments, one premixed combustion setup, equipped with reactant supplying system, is designed and manufactured in Amirkabir University of Technology. In this research, gaseous propane is introduced as fuel and several experiments are performed at nearly atmospheric pressure, with equivalence ratios within the range of 0.7 to 1.5. In this experiments fuel mass flow rate is varied between 2 and 4 gr/s. Unstable operating condition has been observed in combustion chamber when equivalence ratio is less than one. To distinguish the combustion instability for various operating conditions, probability density functions, spectral diagrams, and space distribution of pressure oscillations, along with Rayleigh Criterion, are utilized. Accordingly, effect of equivalence ratio on stabilizing the unstable combustion system is investigated. Moreover, convective delay time is calculated for all experiments and the results are compared with Rayleigh Criterion. This comparison has shown good agreement the experimental results and Rayleigh Criterion. Finally, stability limits are identified based on inlet mass flow rate and equivalence ratio.

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