Prediction of flow instabilities in an atmospheric low swirl burner using urans models Articles uri icon

authors

  • RAMIREZ, JUAN A.
  • CORTES, CRISTOBAL
  • CARRION, ALBERTO
  • CARMONA, MAURICIO
  • LEGRAND, MATHIEU

publication date

  • October 2012

start page

  • 479

end page

  • 498

issue

  • 6

volume

  • 62

international standard serial number (ISSN)

  • 1040-7782

electronic international standard serial number (EISSN)

  • 1521-0634

abstract

  • Swirl-induced phenomena are used in gas turbine burners as a mechanism to stabilize the flame. The formation of coherent structures under turbulent swirling conditions plays a fundamental role in the stabilization and needs to be completely understood also in the absence of combustion. In this work, numerical calculations of the unsteady, Reynolds-averaged Navier-Stokes (URANS) equations for isothermal flow in an unconfined annular low swirl burner (50kW) are reported. The standard k-epsilon and Reynolds stress models are used to run computational cases at a Reynolds number of 12,000 and two swirl numbers (S-L = 0.57 and S-H = 0.64). The numerical method is validated with the experiments reported by Legrand et al. [27]. Numerical results agree well with experiments for mean flow, temporal pressure measurements, and transient coherent structures. 2-D proper orthogonal decomposition (POD), 3-D iso-surfaces and advanced, vortex-related visualization methods are used to document the latter.

keywords

  • tracking velocimetry ptv ; large-eddy simulation ; vortex breakdown ; coherent structures ; combustion characteristics ; numerical simulations ; turbulent flows ; nox emissions ; heat-transfer ; jet