Qualitative assessment of the bi-stable states in the wake of a finite-width double backward facing step
Artikel i vetenskaplig tidskrift, 2019

The flow past a simplified frigate shape model which is analogous to a finite-width double backward facing step is investigated numerically using well-resolved large eddy simulations at Re≃8×104. The geometric configuration of this model permits the occurrence of bi-stable flow states, with an asymmetrical flow topology being observed in the lateral midplane behind each step. In each flow state, the flow at the top step is anti-symmetrical to that observed on the bottom step, and the two flow states are anti-symmetrical to each other. Furthermore, incorporating a base cavity on the top step leads to the suppression of the asymmetrical flow topology on both the steps. The recirculation bubble formed by the downwash at each step is elongated when the base cavity is used, as compared to that observed in either of the two flow states, resulting in a decrease of the drag coefficient. In each of the two flow states, the unequal strength of the streamwise vortices close to the lateral edgeson the top step has been identified as the likely cause of the asymmetrical flow on the bottom step.

Wakes

Författare

Anirudh Narayan Rao

Chalmers, Mekanik och maritima vetenskaper, Strömningslära

Jie Zhang

Chalmers, Mekanik och maritima vetenskaper, Strömningslära

Guglielmo Minelli

Chalmers, Mekanik och maritima vetenskaper, Strömningslära

Branislav Basara

Chalmers, Mekanik och maritima vetenskaper

Sinisa Krajnovic

Chalmers, Mekanik och maritima vetenskaper, Strömningslära

Journal of Wind Engineering and Industrial Aerodynamics

0167-6105 (ISSN)

Vol. 186 241-249

Aktiv strömningskontroll för minskat motstånd för tåg, lastbilar och fartyg

Energimyndigheten, 2016-12-01 -- 2018-08-31.

Drivkrafter

Hållbar utveckling

Styrkeområden

Transport

Ämneskategorier

Teknisk mekanik

Strömningsmekanik och akustik

Fundament

Grundläggande vetenskaper

Infrastruktur

C3SE (Chalmers Centre for Computational Science and Engineering)

DOI

10.1016/j.jweia.2019.01.007

Mer information

Senast uppdaterat

2019-03-12