Hybrid RANS–LES Simulation of Turbulent Heat Transfer in a Channel Flow With Imposed Streamwise or Spanwise Mean Temperature Gradient
| Autor: | Olalekan O. Shobayo, D. Keith Walters |
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| Rok vydání: | 2021 |
| Předmět: |
Physics
business.industry Turbulence Mechanical Engineering 02 engineering and technology Mechanics Computational fluid dynamics 01 natural sciences 010305 fluids & plasmas Open-channel flow Physics::Fluid Dynamics Temperature gradient 020303 mechanical engineering & transports 0203 mechanical engineering Heat flux 0103 physical sciences Mean radiant temperature business Reynolds-averaged Navier–Stokes equations Large eddy simulation |
| Zdroj: | Journal of Fluids Engineering. 143 |
| ISSN: | 1528-901X 0098-2202 |
| DOI: | 10.1115/1.4051067 |
| Popis: | Computational fluid dynamics (CFD) results are presented for turbulent flow and heat transfer in a plane channel. This study investigates an idealized fully developed planar channel flow case for which the mean velocity gradient is nonzero only in the wall-normal direction, and the mean temperature gradient is imposed to be uniform and nonzero in the streamwise or spanwise direction. The objective is to evaluate the accuracy of turbulent heat flux predictions using hybrid Reynolds-averaged Navier–Stokes (RANS)–large eddy simulation (LES) models in wall-bounded flows. Results are obtained at Prandtl number of 0.71 and Reynolds number of 180 based on wall friction velocity and channel half-height and are compared to available direct numerical simulation (DNS) data and to a well-validated RANS model (k–ω shear-stress transport (SST)). The specific hybrid RANS–LES (HRL) models investigated include delayed detached eddy simulation (DDES), improved delayed detached eddy simulation (IDDES), and dynamic hybrid RANS–LES (DHRL). The DHRL model includes both the standard formulation that has been previously documented in the literature as well as a modified version specifically developed to improve predictive capability for flows in which the mean velocity and mean temperature gradients are not closely aligned. The modification consists of using separate RANS-to-LES blending parameters in the momentum and energy equations. Results are interrogated to evaluate the performance of the three different model types and specifically to evaluate the performance of the new modified DHRL variant compared with the baseline version. |
| Databáze: | OpenAIRE |
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