Accessibility navigation


Wake characteristics of multiscale buildings in a turbulent boundary layer

Southgate-Ash, C., Mishra, A., Grimmond, S. ORCID: https://orcid.org/0000-0002-3166-9415, Robins, A. and Placidi, M. (2025) Wake characteristics of multiscale buildings in a turbulent boundary layer. Boundary Layer Meteorology, 191. 20. ISSN 1573-1472

[thumbnail of Open Access]
Preview
Text (Open Access) - Published Version
· Available under License Creative Commons Attribution.
· Please see our End User Agreement before downloading.

3MB
[thumbnail of 2025-BLM_Southgate-Ash.pdf] Text - Accepted Version
· Restricted to Repository staff only

1MB

It is advisable to refer to the publisher's version if you intend to cite from this work. See Guidance on citing.

Abstract/Summary

Urban forms characterised by multi-scale roughness can drastically modify the wind structure within cities affecting both pedestrian comfort and air quality at street level. For simplicity, most urban flow studies focus on cuboid buildings with a single length scale. We consider six forms to assess how additional length scales impact urban flow: two reference cuboid cases (standard and tall) that differ in aspect ratio (mean building height to width), plus two additional fractal iterations of each. The six models have the same mean building width, height, and frontal area but their length scale characteristics differ. These are used in wind tunnel experiments within a deep turbulent boundary layer. The length scale differences are found to affect the drag force exerted by the buildings in a non-negligible way (up to 5% and 13% for standard and tall buildings, respectively). The added length scales also modify the wake lateral spread and intensity of the turbulence fluctuations, with the smaller length scales having the lower (higher) intensity of fluctuations in the near (far) wake. Additionally, the strength of the vortex shedding emanating from the buildings is reduced by introducing systematically smaller length scales. This work suggests that the omission of additional length scales can lead to inaccuracies in drag and wake recovery estimations. The reduction in the intensity of vortex shedding found with each fractal iteration could have engineering applications (e.g. reducing vibration).

Item Type:Article
Refereed:Yes
Divisions:Science > School of Mathematical, Physical and Computational Sciences > Department of Meteorology
ID Code:122644
Uncontrolled Keywords:Drag Measurements · Multi-scale Roughness · Turbulent Boundary Layer · Wake Flows · Wind Tunnel Experiments · Fractal Buildings
Publisher:Springer

Downloads

Downloads per month over past year

University Staff: Request a correction | Centaur Editors: Update this record

Page navigation