An LES investigation of the near-wake flow topology of a simplified heavy vehicle
Journal article, 2018

Recent experimental investigations of McArthur et al (2016) in the wake of
a simplified heavy vehicle or commonly known as the ground transportation
system (GTS) model has shown that the flow topology is invariant over a large
range of Reynolds numbers [2.7 × 104 − 2 × 106]. Numerical simulations are
performed to investigate the initial flow topology at a Reynolds number of 2.7×
104, using well-resolved large eddy simulations (LES). In the vertical midplane
behind the GTS, a flow state which is anti-symmetric to that reported in
McArthur et al (2016) is observed here, thereby, confirming the possibility of
occurrence of the complementary bi-stable flow state. The occurrence of this
bi-stable state does not depend on the ground clearance between the GTS and
the ground plane, as a similar flow topology is observed at both small and large
gap heights. Furthermore, the flow topology in the vertical midplane is also
found to be insensitive to the incoming flow for small yaw angles. However,
complex flow behaviour is observed in the wake for larger yaw angles, where
the flow topology in the vertical midplane becomes nearly symmetric, while an
asymmetric flow topology is now observed in the lateral midplane in the near
wake. Furthermore, the corner vortices which originate from either side at the
front of the model merge in the far wake, leading to a large vortex structure
nearly equal to the height of the model. The near-wake topology of the GTS
is analysed and compared with previous studies for a range of scenarios, and
the forces on the GTS are computed.

Wakes · bi-stability · LES · heavy vehicles

Author

Anirudh Narayan Rao

Chalmers, Mechanics and Maritime Sciences, Fluid Dynamics

Jie Zhang

Chalmers, Mechanics and Maritime Sciences, Fluid Dynamics

Guglielmo Minelli

Chalmers, Mechanics and Maritime Sciences, Fluid Dynamics

Branislav Basara

Chalmers, Mechanics and Maritime Sciences

Sinisa Krajnovic

Chalmers, Mechanics and Maritime Sciences, Fluid Dynamics

Flow, Turbulence and Combustion

1386-6184 (ISSN) 1573-1987 (eISSN)

1386-6184 1-27

Subject Categories

Other Mechanical Engineering

Applied Mechanics

Fluid Mechanics and Acoustics

Driving Forces

Sustainable development

Areas of Advance

Transport

Energy

Roots

Basic sciences

DOI

10.1007/s10494-018-9959-6

More information

Latest update

10/18/2018