Computation of transonic diffuser flows by a lagged κ-ω turbulence model

Q. Xiao, H.M. Tsai, F. Liu

Research output: Contribution to journalArticlepeer-review


The lag model proposed by Olsen and Coakley is applied in combination with the baseline κ-ω two-equation turbulence model to simulate the steady and unsteady transonic flows in a diffuser. A fully implicit time-accurate multigrid algorithm is used to solve the unsteady Navier-Stokes equations and the coupled κ-ω turbulence model equations. Two test cases are investigated, one with a weak shock in the channel corresponding to an exit-static-to-inlet-total pressure ratio Rp=0.82 and the other with a strong shock corresponding to Rp=0.72. Unsteady flows are induced by imposing fluctuating backpressure. Computational results are compared with experimental data and demonstrate notable improvement by the lag model for flows with strong shock-boundary-layer interactions.
Original languageEnglish
Pages (from-to)473-483
Number of pages11
JournalJournal of Propulsion and Power
Issue number3
Publication statusPublished - 31 May 2003


  • algorithms
  • boundary layers
  • diffusers (fluid)
  • mathematical models
  • Navier Stokes equations
  • shock waves
  • steady flow
  • transonic flow
  • turbulence
  • unsteady flow
  • lag model
  • multigrid algorithm
  • transonic diffuser flows
  • aircraft parts and equipment

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