A Numerical Prediction of Stabilized Turbulent Partially Premixed Flames Using Ammonia/Hydrogen Mixture

Authors

  • Moataz Medhat Department of Mechanical Power, Faculty of Engineering, Cairo University, Giza, Egypt
  • Mohamed Yehia Department of Mechanical Power, Faculty of Engineering, Cairo University, Giza, Egypt
  • Adel Khalil Department of Mechanical Power, Faculty of Engineering, Cairo University, Giza, Egypt
  • Miguel C. Franco IDMEC, Mechanical Engineering Department, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal
  • Rodolfo C. Rocha IDMEC, Mechanical Engineering Department, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal

DOI:

https://doi.org/10.37934/arfmts.87.3.113133

Keywords:

Partially premixed, gas turbine combustion, ammonia-hydrogen mixtures, cfd, flame stability

Abstract

The objective of this work is to computationally assess the performance of a carbon free ammonia-hydrogen mixture when burnt in a gas turbine like combustor. Recently, utilizing ammonia as an alternative carbon-free fuel for future power, industry applications and achieving clean energy attracted enormous interest. Pure ammonia oxidation is facing many challenges such as high NOx emissions, high ignition energy, slow reactivity and lower laminar flame speeds. Therefore, the use of ammonia/hydrogen mixture provides flame stability and increasing flame speed. In this manuscript a numerical study for a new swirl stabilized combustor for oxidizing ammonia/hydrogen mixture. Numerical two dimensional model simulations of a turbulent flame on Reynolds Averaged Navier Stokes (RANS) including a realizable k-e turbulent scheme with the aid of chemistry mechanism were performed under various conditions. Partially premixed combustion model with flame-let concept was selected and radiation effects are also considered. Validation for the predicted results showed a reasonable agreement when validated with the experimental data. The results discuss the influence of changing inlet pressure and equivalence ratio on the stability and the characteristics of unburnt NHand NO emissions. Results show that for constant operating conditions such as constant equivalence ratio of 0.8 that increasing hydrogen content resulted in increasing NO emission. Also, for constant ammonia/hydrogen concentrations, NO emissions increases with equivalence ratio then reduced at rich conditions and NHemissions are generally low. Equivalence ratio lower than 1.2 will be preferable to reduce the amount of unburnt NH3 formation.

Author Biographies

Moataz Medhat, Department of Mechanical Power, Faculty of Engineering, Cairo University, Giza, Egypt

motaz.medhat@cu.edu.eg

Mohamed Yehia, Department of Mechanical Power, Faculty of Engineering, Cairo University, Giza, Egypt

myehia@cu.edu.eg

Adel Khalil, Department of Mechanical Power, Faculty of Engineering, Cairo University, Giza, Egypt

adelkhk@yahoo.com

Miguel C. Franco, IDMEC, Mechanical Engineering Department, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal

coelho.franco@tecnico.ulisboa.pt

Rodolfo C. Rocha, IDMEC, Mechanical Engineering Department, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal

rodolfocrocha@tecnico.ulisboa.pt

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Published

2021-10-06

How to Cite

Moataz Medhat, Mohamed Yehia, Adel Khalil, Franco, M. C. ., & Rocha, R. C. . (2021). A Numerical Prediction of Stabilized Turbulent Partially Premixed Flames Using Ammonia/Hydrogen Mixture. Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, 87(3), 113–133. https://doi.org/10.37934/arfmts.87.3.113133

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