Advection scheme effects on large-eddy simulation of
separated turbulent flows past a three-dimensional hill in the weather research and forecasting model
Yong Cao,Tao Tao,Shuyang Cao,Kai Zhang,Dai Zhou
Abstract
Explicitly resolving fine-scale turbulent motions is increasingly prioritized within the Weather Research
and Forecasting - Large-Eddy Simulation (WRF-LES) framework. While much is known about turbulence models
and grid resolution in flat terrain, few studies have evaluated WRF-LES 's performance in resolving separated turbulent
flow past obstacles. This study focuses on flows past a three-dimensional axisymmetric hill, examining the effects of
advection schemes (3rd to 6th order accuracy) and stabilization filters on simulation accuracy and efficiency. These
aspects are often overlooked in WRF-LES practices. We also explore the performance of advection schemes under
varying wind speeds and Smagorinsky coefficients. Results indicate that fundamental coherent structures are
reproduced in the wake of the hill, regardless of the advection scheme. Switching from odd-order to even-order
schemes significantly improve predictions of flow instability and small-scale turbulent motions. Energy spectra show
that even-order schemes better capture the turbulence inertial subrange, achieving nearly twice the effective resolution.
The study finds that numerical dissipation in odd-order schemes diminishes at lower wind speeds. Increasing the off
centering coefficient enhances numerical stability without significantly affecting flow separation or small-scale
turbulence generation.
Key Words
3D hill; advection scheme; large-eddy simulation; weather research and forecasting model
Address
Yong Cao — 1)State Key Laboratory of Ocean Engineering, School of Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China 2)Chongqing Research Institute, Shanghai Jiao Tong University, Chongqing, 401135, China 3)Shenzhen Research Institute, Shanghai Jiao Tong University, Shenzhen 518063, China
Tao Tao — Engineering Research Center of Anhui Green Building and Digital Construction, Anhui Polytechnic University, Wuhu, 241000, China
Shuyang Cao — 5State Key Lab for Disaster Reduction in Civil Engineering, Tongji University, Shanghai, 200092, China
Kai Zhang — State Key Laboratory of Ocean Engineering, School of Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
Dai Zhou — State Key Laboratory of Ocean Engineering, School of Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
PDF Viewer
Preview is limited to the first 3 pages. Sign in to access the full PDF.
