Advanced Combustor Exit Plane Temperature Diagnostics Based on Large Eddy Simulations

Autor: Guillaume Bonneau, Charlie Koupper, Florent Duchaine, Laurent Gicquel
Rok vydání: 2015
Předmět:
Zdroj: Flow, Turbulence and Combustion. 95:79-96
ISSN: 1573-1987
1386-6184
DOI: 10.1007/s10494-015-9607-3
Popis: The accurate description and flow calibration at the exit of a gas turbine combustor is a key point of turbine design. Indeed, the temperature field at the turbine inlet directly impacts both the work extraction by the turbine stages as well as drives the wall heat transfer occurring on the vanes and rotor surfaces. Properly simulating or measuring this critical planar interface has been an extensive topic of research. Despite such efforts, industrial exploitation of the various measures at that interface usually resumes to a quantification of the temperature heterogeneities through the Local Radial Temperature Distortion Factor (LRTDF), thereby loosing major spatial and unsteady information. As lean burn configurations become a standard for aero-engine combustors, the absence of dilution holes reduces the intensity of mixing and the use of more advanced statistical tools should propose an exhaustive representation of the temperature map and mixing quality. Current state-of-the-art numerical design of gas turbine combustor relies on Large Eddy Simulations (LES) giving access to a fully 3-D temporally dependent flow field throughout the combustion chamber. Going beyond LRTDF is therefore possible and advanced analyses of the combustor-turbine interface are accessible to better qualify proposed design changes. In this work, a simple statistical representation of the temperature distribution is introduced and applied for the analysis of a lean burn combustor simulator interface. It is shown that at the exit of this chamber, the temperature samples are distributed following a non-Gaussian shape, highlighting a most probable local temperature largely different from the conventional mean value. The use of high order moments explains such deviations and indicates the presence of strongly segregated zones governed by the technological implementation of effusion cooling systems. Based on this diagnostic, a new and complementary representation of the LRTDF is proposed, accounting for the statistical dimension of the classical (radius, temperature) formulation.
Databáze: OpenAIRE
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