Effects of mesh resolution on large eddy simulation of reacting flows in complex geometry combustors

Journal Article · Wed Oct 15 00:00:00 EDT 2008 · Combustion and Flame

DOI:https://doi.org/10.1016/J.COMBUSTFLAME.2008.04.013· OSTI ID:21116106

Boudier, G; Gicquel, L Y.M. ^[1]; Poinsot, T J ^[2]

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1. CERFACS, 42 Avenue G. Coriolis, 31057 Toulouse cedex (France)
2. Institut de Mecanique des Fluides de Toulouse, Avenue C. Soula, 31400 Toulouse (France)

The power of current parallel computers is becoming sufficient to apply large eddy simulation (LES) tools to reacting flows not only in academic configurations but also in real gas turbine chambers. The most limiting factor in performing LES of real systems is the mesh size, which directly controls the overall cost of the simulation, so that the effects of mesh resolution on LES results become a key issue. In the present work, an unstructured compressible LES solver is used to compute the reacting flow in a domain corresponding to a sector of a realistic helicopter chamber. Three grids ranging from 1.2 to 44 million elements are used for LES and results are compared in terms of mean and fluctuating fields as well as of pressure spectra. Results show that the mean temperature, reaction rate, and velocity fields are almost insensitive to the grid size. The RMS field of the resolved velocity is also reasonably independent of the mesh, while the RMS fields of temperature exhibit more sensitivity to the grid, as expected from the fact that most of the combustion process proceeds at small scales. The acoustic field exhibits a limited sensitivity to the mesh, suggesting that LES is adapted to the computation of combustion instabilities in complex systems. (author)

• OSTI ID: 21116106
• Journal Information: Combustion and Flame, Vol. 155, Issue 1-2; Other Information: Elsevier Ltd. All rights reserved; ISSN 0010-2180
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
GAS TURBINES
COORDINATES
COMPUTERIZED SIMULATION
RESOLUTION
COMBUSTION
COMBUSTION INSTABILITY
REACTION KINETICS
COMBUSTORS
HELICOPTERS
SENSITIVITY
VELOCITY
CALCULATION METHODS
COMBUSTION CHAMBERS
CONFIGURATION
COST
SPECTRA
COMPUTER CALCULATIONS
Mesh resolution
Large eddy simulations