Fast and accurate CFD-model for NOx emission prediction during oxy-fuel combustion of natural gas using detailed chemical kinetics

C. Schluckner, C. Gaber, M. Landfahrer, M. Demuth, C. Hochenauer

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Accurate prediction of NOx emission is essential in designing combustion devices and troubleshooting of existing ones. The aim of this work is to investigate the sensitivity of NOx formation during the combustion of natural gas with oxygen using a numerically inexpensive computational fluid dynamics model. To this end, an industrial jet burner was experimentally and numerically analysed for NOx formation at 600 kW controlled at 1320 and 1450°C during the combustion of natural gas with pure oxygen and oxidizer mixtures containing up to 10%v nitrogen. Two mixture-fraction based and two classical species transport models were investigated for their ability to: (1) predict the flame shape and temperature, (2) calculate the OH and CH emissions driving the NOx formation, and (3) fast and accurately predict the NOx emissions during oxy-fuel combustion and during the presence of low nitrogen amounts in the oxidizer. The study shows that the widely-used steady-flamelet model fails to correctly predict the flame shape and temperature, due to a too low velocity difference between the oxidizer and the fuel. It is highlighted that only the partially-premixed steady flamelet model predicted the flame shape and the NOx formation rates adequately, fitting the experimental and numerical data closely. Moreover, the shear rate in the annular gap was identified as a crucial parameter for the applicability of mixture fraction-based models. Species transport models should be used for validity checks but they disqualify as fast-solving alternatives due to their high computational demand (EDC) or lack of detailed chemistry interaction (EDM).

Original languageEnglish
Article number116841
JournalFuel
Volume264
DOIs
Publication statusPublished - 15 Mar 2020

Fingerprint

Reaction kinetics
Natural gas
Computational fluid dynamics
Nitrogen
Oxygen
Fuel burners
Shear deformation
Dynamic models
Temperature

Keywords

  • CFD NOx study
  • Detailed combustion chemistry
  • OEC and oxy-fuel natural gas combustion
  • Semi-industrial burner chamber

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Fuel Technology
  • Energy Engineering and Power Technology
  • Organic Chemistry

Cite this

Fast and accurate CFD-model for NOx emission prediction during oxy-fuel combustion of natural gas using detailed chemical kinetics. / Schluckner, C.; Gaber, C.; Landfahrer, M.; Demuth, M.; Hochenauer, C.

In: Fuel, Vol. 264, 116841, 15.03.2020.

Research output: Contribution to journalArticleResearchpeer-review

@article{fea84679799a447bb4d4ebf400c763d3,
title = "Fast and accurate CFD-model for NOx emission prediction during oxy-fuel combustion of natural gas using detailed chemical kinetics",
abstract = "Accurate prediction of NOx emission is essential in designing combustion devices and troubleshooting of existing ones. The aim of this work is to investigate the sensitivity of NOx formation during the combustion of natural gas with oxygen using a numerically inexpensive computational fluid dynamics model. To this end, an industrial jet burner was experimentally and numerically analysed for NOx formation at 600 kW controlled at 1320 and 1450°C during the combustion of natural gas with pure oxygen and oxidizer mixtures containing up to 10{\%}v nitrogen. Two mixture-fraction based and two classical species transport models were investigated for their ability to: (1) predict the flame shape and temperature, (2) calculate the OH and CH emissions driving the NOx formation, and (3) fast and accurately predict the NOx emissions during oxy-fuel combustion and during the presence of low nitrogen amounts in the oxidizer. The study shows that the widely-used steady-flamelet model fails to correctly predict the flame shape and temperature, due to a too low velocity difference between the oxidizer and the fuel. It is highlighted that only the partially-premixed steady flamelet model predicted the flame shape and the NOx formation rates adequately, fitting the experimental and numerical data closely. Moreover, the shear rate in the annular gap was identified as a crucial parameter for the applicability of mixture fraction-based models. Species transport models should be used for validity checks but they disqualify as fast-solving alternatives due to their high computational demand (EDC) or lack of detailed chemistry interaction (EDM).",
keywords = "CFD NOx study, Detailed combustion chemistry, OEC and oxy-fuel natural gas combustion, Semi-industrial burner chamber",
author = "C. Schluckner and C. Gaber and M. Landfahrer and M. Demuth and C. Hochenauer",
year = "2020",
month = "3",
day = "15",
doi = "10.1016/j.fuel.2019.116841",
language = "English",
volume = "264",
journal = "Fuel",
issn = "0016-2361",
publisher = "Elsevier B.V.",

}

TY - JOUR

T1 - Fast and accurate CFD-model for NOx emission prediction during oxy-fuel combustion of natural gas using detailed chemical kinetics

AU - Schluckner, C.

AU - Gaber, C.

AU - Landfahrer, M.

AU - Demuth, M.

AU - Hochenauer, C.

PY - 2020/3/15

Y1 - 2020/3/15

N2 - Accurate prediction of NOx emission is essential in designing combustion devices and troubleshooting of existing ones. The aim of this work is to investigate the sensitivity of NOx formation during the combustion of natural gas with oxygen using a numerically inexpensive computational fluid dynamics model. To this end, an industrial jet burner was experimentally and numerically analysed for NOx formation at 600 kW controlled at 1320 and 1450°C during the combustion of natural gas with pure oxygen and oxidizer mixtures containing up to 10%v nitrogen. Two mixture-fraction based and two classical species transport models were investigated for their ability to: (1) predict the flame shape and temperature, (2) calculate the OH and CH emissions driving the NOx formation, and (3) fast and accurately predict the NOx emissions during oxy-fuel combustion and during the presence of low nitrogen amounts in the oxidizer. The study shows that the widely-used steady-flamelet model fails to correctly predict the flame shape and temperature, due to a too low velocity difference between the oxidizer and the fuel. It is highlighted that only the partially-premixed steady flamelet model predicted the flame shape and the NOx formation rates adequately, fitting the experimental and numerical data closely. Moreover, the shear rate in the annular gap was identified as a crucial parameter for the applicability of mixture fraction-based models. Species transport models should be used for validity checks but they disqualify as fast-solving alternatives due to their high computational demand (EDC) or lack of detailed chemistry interaction (EDM).

AB - Accurate prediction of NOx emission is essential in designing combustion devices and troubleshooting of existing ones. The aim of this work is to investigate the sensitivity of NOx formation during the combustion of natural gas with oxygen using a numerically inexpensive computational fluid dynamics model. To this end, an industrial jet burner was experimentally and numerically analysed for NOx formation at 600 kW controlled at 1320 and 1450°C during the combustion of natural gas with pure oxygen and oxidizer mixtures containing up to 10%v nitrogen. Two mixture-fraction based and two classical species transport models were investigated for their ability to: (1) predict the flame shape and temperature, (2) calculate the OH and CH emissions driving the NOx formation, and (3) fast and accurately predict the NOx emissions during oxy-fuel combustion and during the presence of low nitrogen amounts in the oxidizer. The study shows that the widely-used steady-flamelet model fails to correctly predict the flame shape and temperature, due to a too low velocity difference between the oxidizer and the fuel. It is highlighted that only the partially-premixed steady flamelet model predicted the flame shape and the NOx formation rates adequately, fitting the experimental and numerical data closely. Moreover, the shear rate in the annular gap was identified as a crucial parameter for the applicability of mixture fraction-based models. Species transport models should be used for validity checks but they disqualify as fast-solving alternatives due to their high computational demand (EDC) or lack of detailed chemistry interaction (EDM).

KW - CFD NOx study

KW - Detailed combustion chemistry

KW - OEC and oxy-fuel natural gas combustion

KW - Semi-industrial burner chamber

UR - http://www.scopus.com/inward/record.url?scp=85076859227&partnerID=8YFLogxK

U2 - 10.1016/j.fuel.2019.116841

DO - 10.1016/j.fuel.2019.116841

M3 - Article

VL - 264

JO - Fuel

JF - Fuel

SN - 0016-2361

M1 - 116841

ER -