A Shifted Boundary Method for Thermal Flows

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Yang, Cheng-Hau, Scovazzi, Guglielmo, Krishnamurthy, Adarsh, Ganapathysubramanian, Baskar
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913687515693056
author Yang, Cheng-Hau
Scovazzi, Guglielmo
Krishnamurthy, Adarsh
Ganapathysubramanian, Baskar
author_facet Yang, Cheng-Hau
Scovazzi, Guglielmo
Krishnamurthy, Adarsh
Ganapathysubramanian, Baskar
contents This paper presents an incomplete Octree mesh implementation of the Shifted Boundary Method (Octree-SBM) for multiphysics simulations of coupled flow and heat transfer. Specifically, a semi-implicit formulation of the thermal Navier-Stokes equations is used to accelerate the simulations while maintaining accuracy. The SBM enables precise enforcement of field and derivative boundary conditions on cut (intercepted) elements, allowing for accurate flux calculations near complex geometries, when using non-boundary fitted meshes. Both Dirichlet and Neumann boundary conditions are implemented within the SBM framework, with results demonstrating that the SBM ensures precise enforcement of Neumann boundary conditions on Octree-based meshes. We illustrate this approach by simulating flows across different regimes, spanning several orders of magnitude in both the Rayleigh number ($Ra \sim 10^3$--$10^9$) and the Reynolds number ($Re \sim 10^0$--$10^4$), and covering the laminar, transitional, and turbulent flow regimes. Coupled thermal-flow phenomena and their statistics across all these regimes are accurately captured without any additional numerical treatments, beyond a Residual-based Variational Multiscale formulation (RB-VMS). This approach offers a reliable and efficient solution for complex geometries, boundary conditions and flow regimes in computational multiphysics simulations.
format Preprint
id arxiv_https___arxiv_org_abs_2501_00143
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle A Shifted Boundary Method for Thermal Flows
Yang, Cheng-Hau
Scovazzi, Guglielmo
Krishnamurthy, Adarsh
Ganapathysubramanian, Baskar
Fluid Dynamics
Numerical Analysis
This paper presents an incomplete Octree mesh implementation of the Shifted Boundary Method (Octree-SBM) for multiphysics simulations of coupled flow and heat transfer. Specifically, a semi-implicit formulation of the thermal Navier-Stokes equations is used to accelerate the simulations while maintaining accuracy. The SBM enables precise enforcement of field and derivative boundary conditions on cut (intercepted) elements, allowing for accurate flux calculations near complex geometries, when using non-boundary fitted meshes. Both Dirichlet and Neumann boundary conditions are implemented within the SBM framework, with results demonstrating that the SBM ensures precise enforcement of Neumann boundary conditions on Octree-based meshes. We illustrate this approach by simulating flows across different regimes, spanning several orders of magnitude in both the Rayleigh number ($Ra \sim 10^3$--$10^9$) and the Reynolds number ($Re \sim 10^0$--$10^4$), and covering the laminar, transitional, and turbulent flow regimes. Coupled thermal-flow phenomena and their statistics across all these regimes are accurately captured without any additional numerical treatments, beyond a Residual-based Variational Multiscale formulation (RB-VMS). This approach offers a reliable and efficient solution for complex geometries, boundary conditions and flow regimes in computational multiphysics simulations.
title A Shifted Boundary Method for Thermal Flows
topic Fluid Dynamics
Numerical Analysis
url https://arxiv.org/abs/2501.00143