Numerical and chemical kinetic analysis to evaluate the effect of steam dilution and pressure on combustion of n-dodecane in a swirling flow environment
Lee, Bok Jik
Elbaz, Ayman M.
Roberts, William L.
Dash, Sukanta Kumar
Reddy, V. Mahendra
KAUST DepartmentClean Combustion Research Center
Physical Science and Engineering (PSE) Division
Mechanical Engineering Program
KAUST Grant NumberCRG
Embargo End Date2022-11-01
Permanent link to this recordhttp://hdl.handle.net/10754/666350
MetadataShow full item record
AbstractIn the present study, numerical analysis on the effect of steam dilution and high pressure on liquid fuel swirl combustion is carried out using a turbulent non-premixed combustion model. Tangential air injection scheme is adopted in a conical combustor. High recirculation is achieved inside the combustor due to the swirl pattern produced by the tangential air inlets. n-Dodecane, which is a major component of kerosene and Jet-A fuel, is selected as fuel in the present study. The thermal intensity of 5.37 MW/m3 with 21.1 kW thermal input is considered for the computational study. The chamber pressure is varied from 1 to 20 atm, keeping the momentum of inlet airflow constant. Steam added in the oxidizer as a diluent is varied from 0 to 20% by mass. Computational Fluid Dynamics (CFD) analysis using RANS (Reynolds Averaged Navier-Stokes) equations is performed to understand the flow characteristics and study the effect of steam dilution and pressure on NO formation. Realizable k-ε turbulence model is used in the present study to capture the flow behavior due to the swirling motion. Spray characteristics are modelled using the Discrete Phase Model. The chemical representation is realized using scalar conservation concept with β-PDF model. Detailed chemical kinetic analysis with ignition delay characteristics, rate of species production, reaction behavior and sensitivity analysis is carried out. It is observed that the ignition delay decreases rapidly with pressure and very slowly with steam dilution. Effect of pressure and dilution on the OH concentration and olefins are discussed. Peak flame temperature and NO formation decreased with the steam addition. Emission characteristics are presented in the paper.
CitationMohapatra, S., Garnayak, S., Lee, B. J., Elbaz, A. M., Roberts, W. L., Dash, S. K., & Reddy, V. M. (2020). Numerical and chemical kinetic analysis to evaluate the effect of steam dilution and pressure on combustion of n-dodecane in a swirling flow environment. Fuel, 119710. doi:10.1016/j.fuel.2020.119710
SponsorsThe authors (SM, SG, SKD and VMR) would like to acknowledge the funding received for this work from Science and Engineering Research Board (SERB) of India under Core Research Grant (Grant no-CRG/2019/005882). BJL would like to acknowledge the support by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry and Energy (MOTIE) of the Republic of Korea (Grant No. 20181110100290). For the KAUST team (AME and WLR), the research reported in this publication was supported by the Office of Sponsored Research (OSR) at King Abdullah University of Science and Technology (KAUST).