Search for dissertations about: "log-layer mismatch"

Found 2 swedish dissertations containing the words log-layer mismatch.

  1. 1. Methodologies for RANS-LES interfaces in turbulence-resolving simulations

    Author : Sebastian Arvidson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; zonal RANS-LES; aeronautics; RANS-LES interfaces; Hybrid RANS-LES; grey-area mitigation; log-layer mismatch; embedded LES; LES length scale; LES;

    Abstract : Hybrid Reynolds-Average Navier-Stokes (RANS)-Large-Eddy Simulations (LES) techniques are now seen by the aeronautical industry as the most promising turbulence-resolving approaches for complex high-Reynolds-number turbulent flows with regard to cost and accuracy. However, connecting RANS and LES simulated flows is a challenging task and needs special attention in order to increase simulation robustness and accuracy. READ MORE

  2. 2. Assessment and Some Improvements of Hybrid RANS-LES Methods

    Author : Sebastian Arvidson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LES; hybrid RANS-LES; zonal RANS-LES; embedded LES; PDH-LRN; log-layer mismatch; LES length scale; shock boundary-layer interaction;

    Abstract : Motivated by numerical analysis of a shock/boundary-layer interacting (SBLI) flow in a duct, where some typical existing hybrid RANS-LES methods become awkward to give accurate predictions of the shock-induced corner separation bubble, a new hybrid RANS-LES method, has been proposed. The model is based on a low-Reynolds-number (LRN) $k-\omega$ RANS model, which is one of the few models that are capable of giving reasonable predictions for the SBLI flow in RANS computations. READ MORE