Non-symmetric bi-stable flow around the Ahmed body

Walter Meile; Thomas Ladinek; Günter Brenn; Aaron Reppenhagen; Anton Fuchs

doi:10.1016/j.ijheatfluidflow.2015.11.002

Non-symmetric bi-stable flow around the Ahmed body

Walter Meile, Thomas Ladinek, Günter Brenn, Aaron Reppenhagen, Anton Fuchs

Research output: Contribution to journal › Article › peer-review

Abstract

The flow around the Ahmed body at varying Reynolds numbers under yawing conditions is investigated experimentally. The body geometry belongs to a regime subject to spanwise flow instability identified in symmetric flow by Cadot and co-workers (Grandemange et al., 2013b). Our experiments cover the two slant angles 25° and 35° and Reynolds numbers up to 2.784 × 106. Special emphasis lies on the aerodynamics under side wind influence. For the 35° slant angle, forces and moments change significantly with the yawing angle in the range 10° ≤ |β| ≤ 15°. The lift and the pitching moment exhibit strong fluctuations due to bi-stable flow around a critical angle β of ±12.5°, where the pitching moment changes sign. Time series of the forces and moments are studied and explained by PIV measurements in the flow field near the rear of the body.

Original language	English
Pages (from-to)	34-47
Journal	International Journal of Heat and Fluid Flow
Volume	57
DOIs	https://doi.org/10.1016/j.ijheatfluidflow.2015.11.002
Publication status	Published - 2016

Fields of Expertise

Mobility & Production

Access to Document

10.1016/j.ijheatfluidflow.2015.11.002

Aerodynamik von Kraftfahrzeuge - Automobile Aerodynamics
Brenn, G. & Meile, W.
1/08/07 → 31/01/09
Project: Research project

Cite this

@article{e80a6d04872049378ecfed981ba74230,

title = "Non-symmetric bi-stable flow around the Ahmed body",

abstract = "The flow around the Ahmed body at varying Reynolds numbers under yawing conditions is investigated experimentally. The body geometry belongs to a regime subject to spanwise flow instability identified in symmetric flow by Cadot and co-workers (Grandemange et al., 2013b). Our experiments cover the two slant angles 25° and 35° and Reynolds numbers up to 2.784 × 106. Special emphasis lies on the aerodynamics under side wind influence. For the 35° slant angle, forces and moments change significantly with the yawing angle in the range 10° ≤ |β| ≤ 15°. The lift and the pitching moment exhibit strong fluctuations due to bi-stable flow around a critical angle β of ±12.5°, where the pitching moment changes sign. Time series of the forces and moments are studied and explained by PIV measurements in the flow field near the rear of the body.",

author = "Walter Meile and Thomas Ladinek and G{\"u}nter Brenn and Aaron Reppenhagen and Anton Fuchs",

year = "2016",

doi = "10.1016/j.ijheatfluidflow.2015.11.002",

language = "English",

volume = "57",

pages = "34--47",

journal = "International Journal of Heat and Fluid Flow",

issn = "1879-2278",

publisher = "Elsevier B.V.",

}

TY - JOUR

T1 - Non-symmetric bi-stable flow around the Ahmed body

AU - Meile, Walter

AU - Ladinek, Thomas

AU - Brenn, Günter

AU - Reppenhagen, Aaron

AU - Fuchs, Anton

PY - 2016

Y1 - 2016

N2 - The flow around the Ahmed body at varying Reynolds numbers under yawing conditions is investigated experimentally. The body geometry belongs to a regime subject to spanwise flow instability identified in symmetric flow by Cadot and co-workers (Grandemange et al., 2013b). Our experiments cover the two slant angles 25° and 35° and Reynolds numbers up to 2.784 × 106. Special emphasis lies on the aerodynamics under side wind influence. For the 35° slant angle, forces and moments change significantly with the yawing angle in the range 10° ≤ |β| ≤ 15°. The lift and the pitching moment exhibit strong fluctuations due to bi-stable flow around a critical angle β of ±12.5°, where the pitching moment changes sign. Time series of the forces and moments are studied and explained by PIV measurements in the flow field near the rear of the body.

AB - The flow around the Ahmed body at varying Reynolds numbers under yawing conditions is investigated experimentally. The body geometry belongs to a regime subject to spanwise flow instability identified in symmetric flow by Cadot and co-workers (Grandemange et al., 2013b). Our experiments cover the two slant angles 25° and 35° and Reynolds numbers up to 2.784 × 106. Special emphasis lies on the aerodynamics under side wind influence. For the 35° slant angle, forces and moments change significantly with the yawing angle in the range 10° ≤ |β| ≤ 15°. The lift and the pitching moment exhibit strong fluctuations due to bi-stable flow around a critical angle β of ±12.5°, where the pitching moment changes sign. Time series of the forces and moments are studied and explained by PIV measurements in the flow field near the rear of the body.

U2 - 10.1016/j.ijheatfluidflow.2015.11.002

DO - 10.1016/j.ijheatfluidflow.2015.11.002

M3 - Article

SN - 1879-2278

VL - 57

SP - 34

EP - 47

JO - International Journal of Heat and Fluid Flow

JF - International Journal of Heat and Fluid Flow

ER -

Non-symmetric bi-stable flow around the Ahmed body

Abstract

Fields of Expertise

Access to Document

Fingerprint

Projects

Aerodynamik von Kraftfahrzeuge - Automobile Aerodynamics

Cite this