Experiments and numerical studies on a Syngas-fired Ultra low NOx combustor

Handle URI:
http://hdl.handle.net/10754/624903
Title:
Experiments and numerical studies on a Syngas-fired Ultra low NOx combustor
Authors:
S, Krishna; Ravikrishna, R. V.
Abstract:
Exhaust measurements of temperature and pollutants in a syngas-fired model trapped vortex combustor for stationary power generation applications are reported. The performance was further evaluated for configurations where mixing enhancement was obtained using struts in the mainstream flow. Mainstream premixing of fuel was also studied to investigate its effect on emissions. The exhaust temperature pattern factor was found to be poor for baseline cases, but improved with the introduction of struts. NO emissions were steadily below 3-ppm across various flow conditions, whereas CO emissions tended to increase with increasing Momentum Flux Ratios (MFRs) and mainstream fuel addition. Combustion efficiencies ~96% were observed for all conditions. The performance characteristics were found to be favourable at higher MFRs with low pattern factors and high combustion efficiencies. Numerical simulations employing RANS and LES with Presumed Probability Distribution Function (PPDF) model were also carried out. Mixture fraction profiles in the TVC cavity for non-reacting conditions show that LES simulations are able to capture the mean mixing field better than the RANS-based approach. This is attributed to the prediction of the jet decay rate and is reflected on the mean velocity magnitude fields, which reinforce this observation at different sections in the cavity. Both RANS and LES simulations show close agreement with the experimentally measured OH concentration, however, the RANS approach does not perform satisfactorily in capturing the trend of velocity magnitude. LES simulations clearly capture the trend observed in exhaust measurements which is primarily attributed to the flame stabilization mechanism.
KAUST Department:
Clean Combustion Research Center
Citation:
S K, Ravikrishna RV (2017) Experiments and numerical studies on a Syngas-fired Ultra low NOx combustor. Journal of Engineering for Gas Turbines and Power. Available: http://dx.doi.org/10.1115/1.4036945.
Publisher:
ASME International
Journal:
Journal of Engineering for Gas Turbines and Power
Issue Date:
6-Jun-2017
DOI:
10.1115/1.4036945
Type:
Article
ISSN:
0742-4795
Additional Links:
http://gasturbinespower.asmedigitalcollection.asme.org/article.aspx?articleid=2631256
Appears in Collections:
Articles; Clean Combustion Research Center

Full metadata record

DC FieldValue Language
dc.contributor.authorS, Krishnaen
dc.contributor.authorRavikrishna, R. V.en
dc.date.accessioned2017-06-12T08:33:42Z-
dc.date.available2017-06-12T08:33:42Z-
dc.date.issued2017-06-06en
dc.identifier.citationS K, Ravikrishna RV (2017) Experiments and numerical studies on a Syngas-fired Ultra low NOx combustor. Journal of Engineering for Gas Turbines and Power. Available: http://dx.doi.org/10.1115/1.4036945.en
dc.identifier.issn0742-4795en
dc.identifier.doi10.1115/1.4036945en
dc.identifier.urihttp://hdl.handle.net/10754/624903-
dc.description.abstractExhaust measurements of temperature and pollutants in a syngas-fired model trapped vortex combustor for stationary power generation applications are reported. The performance was further evaluated for configurations where mixing enhancement was obtained using struts in the mainstream flow. Mainstream premixing of fuel was also studied to investigate its effect on emissions. The exhaust temperature pattern factor was found to be poor for baseline cases, but improved with the introduction of struts. NO emissions were steadily below 3-ppm across various flow conditions, whereas CO emissions tended to increase with increasing Momentum Flux Ratios (MFRs) and mainstream fuel addition. Combustion efficiencies ~96% were observed for all conditions. The performance characteristics were found to be favourable at higher MFRs with low pattern factors and high combustion efficiencies. Numerical simulations employing RANS and LES with Presumed Probability Distribution Function (PPDF) model were also carried out. Mixture fraction profiles in the TVC cavity for non-reacting conditions show that LES simulations are able to capture the mean mixing field better than the RANS-based approach. This is attributed to the prediction of the jet decay rate and is reflected on the mean velocity magnitude fields, which reinforce this observation at different sections in the cavity. Both RANS and LES simulations show close agreement with the experimentally measured OH concentration, however, the RANS approach does not perform satisfactorily in capturing the trend of velocity magnitude. LES simulations clearly capture the trend observed in exhaust measurements which is primarily attributed to the flame stabilization mechanism.en
dc.publisherASME Internationalen
dc.relation.urlhttp://gasturbinespower.asmedigitalcollection.asme.org/article.aspx?articleid=2631256en
dc.rightsArchived with thanks to Journal of Engineering for Gas Turbines and Poweren
dc.subjectCombustion chambersen
dc.subjectSyngasen
dc.subjectNitrogen oxidesen
dc.subjectReynolds-averaged Navier–Stokes equationsen
dc.subjectExhaust systemsen
dc.subjectEngineering simulationen
dc.subjectSimulationen
dc.subjectEmissionsen
dc.subjectFlow (Dynamics)en
dc.subjectTemperatureen
dc.titleExperiments and numerical studies on a Syngas-fired Ultra low NOx combustoren
dc.typeArticleen
dc.contributor.departmentClean Combustion Research Centeren
dc.identifier.journalJournal of Engineering for Gas Turbines and Poweren
dc.eprint.versionPost-printen
dc.contributor.institutionCombustion and Spray Laboratory, Department of Mechanical Engineering, Indian Institute of Scienceen
kaust.authorS, Krishnaen
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