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Title: PeleLM-FDF large eddy simulator of turbulent reacting flows
A new computational methodology, termed ‘PeleLM-FDF’ is developed and utilised for high fidelity large eddy simulation (LES) of complex turbulent combustion systems. This methodology is constructed via a hybrid scheme combining the Eulerian PeleLM base flow solver with the Lagrangian Monte Carlo simulator of the filtered density func- tion (FDF) for the subgrid scale reactive scalars. The resulting methodology is capable of simulating some of the most intricate physics of complex turbulence-combustion interactions. This is demonstrated by LES of a non-premixed CO/H2 temporally evolv- ing jet flame. The chemistry is modelled via a skeletal kinetics model, and the results are appraised via a posteriori comparisons against direct numerical simulation (DNS) data of the same flame. Excellent agreements are observed for the time evolution of various statistics of the thermo-chemical quantities, including the manifolds of the multi-scalar mixing. The new methodology is capable of capturing the complex phe- nomena of flame-extinction and re-ignition at a 1/512 of the computational cost of the DNS. The high fidelity and the computational affordability of the new PeleLM-FDF solver warrants its consideration for LES of practical turbulent combustion systems.  more » « less
Award ID(s):
2152803
PAR ID:
10425276
Author(s) / Creator(s):
Editor(s):
Taylor and Francis
Date Published:
Journal Name:
Combustion theory and modelling
Volume:
26
Issue:
6
ISSN:
1364-7830
Page Range / eLocation ID:
1--18
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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