Challenges for large eddy simulation of partially premixed turbulent combustion using reduced-order manifold flame structure models

Bruce A. Perry, Michael E. Mueller

Research output: Contribution to conferencePaperpeer-review

1 Scopus citations


Partial premixing and the presence of multiple inlet streams are key features of many modern paradigms in combustion engine design but lead to systems that simultaneously involve premixed-like, nonpremixed-like, and intermediate combustion modes. In contrast, the classical reduced-order flame structure models used for Large Eddy Simulation (LES), such as "flamelet"-like models, are derived assuming a single dominant mode. A variety of reduced-order manifold approaches have been developed that attempt to model multi-modal combustion by switching between the classical single-mode models based on a parameter that indicates which mode is locally dominant. In this work, three approaches for including multi-modal effects in LES are compared for the case of a piloted jet burner with inhomogeneous inlets. These approaches are all based on an extended nonpremixed model that uses two mixture fractions to account for partial premixing of the fuel stream but use different methods of incorporating premixed combustion effects. Although the multi-modal models have shown improved predictions relative to single-mode models, they result in additional modeling challenges and still do not accurately predict the flame structure in all regions of the flame. Potential causes for the remaining inaccuracy in the predictions are assessed. In particular, the limitations of applying combustion models that rely on a 1D flame structure and are based on either premixed or nonpremixed combustion to a partially premixed system are discussed.

Original languageAmerican English
StatePublished - 2018
Event2018 Spring Technical Meeting of the Eastern States Section of the Combustion Institute, ESSCI 2018 - State College, United States
Duration: Mar 4 2018Mar 7 2018


Other2018 Spring Technical Meeting of the Eastern States Section of the Combustion Institute, ESSCI 2018
Country/TerritoryUnited States
CityState College

ASJC Scopus subject areas

  • Mechanical Engineering
  • Physical and Theoretical Chemistry
  • General Chemical Engineering


  • Large eddy simulation
  • Partially premixed combustion
  • Reduced-order manifolds

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