Webbläsaren som du använder stöds inte av denna webbplats. Alla versioner av Internet Explorer stöds inte längre, av oss eller Microsoft (läs mer här: * https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Var god och använd en modern webbläsare för att ta del av denna webbplats, som t.ex. nyaste versioner av Edge, Chrome, Firefox eller Safari osv.

Investigation of two-equation turbulence models applied to a confined axis-symmetric swirling flow

Författare

Summary, in English

The modeling of industrial combustion applications today is almost exclusively based on two-equation turbulence models. Despite its known limitations, the most the widely used model is still the standard k-ε model. The objective of this paper is to investigate the performance of two-equation turbulence models applied to a confined swirling flow. Numerical modeling of an axis-symmetric confined sudden expansion, followed by a contraction with the assumption of steady flow and an incompressible fluid, has been conducted. The flow field is what can be expected in simplified dump gas turbine combustor geometry. In this investigation, three different swirl cases were considered: no swirl, moderate swirl (no central re-circulation zone) and strong swift (a central recirculation zone occurring). The models investigated were: the standard k-ε model, a curvature-modified k-ε model, Chen's k-ε model, a cubic non-linear k-ε model, the standard k-ω model and the Shear Stress Transport (SST) k-ω model. The results show that almost all models were able to predict the major impact of the moderate swirl: reduced outer re-circulation lengths and retardation of the axial velocity on the center-line. However, the Chen k-ε model and the SST k-ω model were found to better reproduce the mean velocity field and the turbulent kinetic energy field from the measurements. For a strong swift, a large re-circulation zone is formed along the center-line, which the standard k-ε model and the modified k-ε model fail to predict. However, the shape and size of the re-circulation zone differ strongly between the models. At this swirl number, the performances of all models were, without exception, worse than for the lower swift numbers. The SST k-ω model achieved the best agreement between computations and experimental data.

Avdelning/ar

Publiceringsår

2002

Språk

Engelska

Sidor

199-206

Publikation/Tidskrift/Serie

American Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication) PVP

Volym

448

Issue

2

Dokumenttyp

Konferensbidrag

Förlag

American Society Of Mechanical Engineers (ASME)

Ämne

  • Energy Engineering

Nyckelord

  • Gas turbine combustors

Conference name

Computational technologies for Fluid/Thermal/Structural/Chemical Systems with Industrial Applications (2002 ASME Prssure Vessels and Piping Conference)

Conference date

2002-08-05 - 2002-08-09

Conference place

Vancouver, BC, Canada

Status

Published

ISBN/ISSN/Övrigt

  • ISSN: 0277-027X
  • CODEN: AMPPD5