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Title: Subgrid modeling of reaction-rate using a multi-scale strategy for large-eddy simulation of turbulent combustion
In this study, we examine the performance of a multi-scale model for large-eddy simulation (LES) of tur- bulent combustion. The model referred to as RRLES performs the closure of the filtered reaction-rate term in the species transport equation while performing LES by using the linear eddy mixing (LEM) model. The RRLES model uses a multi-scale strategy to obtain the filtered reaction rate of the species and has been shown to address some of the challenges associated with the well-established LEMLES approach. The orig- inally proposed RRLES strategy used a multilevel adaptive mesh refinement (AMR) framework, which was extended to use a single grid-based strategy to enable the application to complex geometries. Additionally, a local dual-resolution grid strategy has also been developed and can potentially be used with different grid topologies, without the need for the AMR. We assess the accuracy and efficiency of the single and dual-grid RRLES approaches by considering a freely propagating turbulent premixed flame under two different initial conditions corresponding to the thin reaction zone (TRZ) and the broken/distributed reaction zone (B/DRZ) regimes.  more » « less
Award ID(s):
2301829
PAR ID:
10505520
Author(s) / Creator(s):
; ;
Publisher / Repository:
American Society of Thermal and Fluid Engineers
Date Published:
Journal Name:
Thermal and Fluids Engineering Conference
Format(s):
Medium: X
Location:
Oregon State University, OR
Sponsoring Org:
National Science Foundation
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