Dominant flow structures in the wake of a cyclist

Timothy N. Crouch, Mark Thompson, David Burton, John Sheridan, Nicholas A T Brown

Research output: A Conference proceeding or a Chapter in BookConference contribution

4 Citations (Scopus)

Abstract

In this wind tunnel investigation the time-averaged wake structure is analyzed for a full scale cyclist mannequin over a complete crank cycle. At typical elite level road cycling speeds, detailed velocity field measurements were performed by traversing a four-hole dynamic pressure probe in planes behind the mannequin for 15° increments in crank position. They highlight the complexity of flows associated with cyclist geometries and show that variations in drag with leg position are primarily attributed to changes in the flow regime and not frontal surface area. The wake is shown to be highly three-dimensional with the primary flow structures consisting of multiple streamwise vortices. The formation strength and interaction of these structures about the center plane of the mannequin depend on whether each leg is in an up or down position around the crank cycle. This dependence on the position of each leg results in an asymmetrical wake configuration for the majority of crank positions tested. This is further highlighted in a series of flow visualization studies showing the origin and asymmetry in the formation of these structures over the upper body with crank position. This work highlights the importance of considering multiple flow regimes when investigating the aerodynamic performance of cyclists.

Original languageEnglish
Title of host publication30th AIAA Applied Aerodynamics Conference 2012
Pages2022-2031
Number of pages10
DOIs
Publication statusPublished - 1 Dec 2012
Event30th AIAA Applied Aerodynamics Conference 2012 - New Orleans, LA, United States
Duration: 25 Jun 201228 Jun 2012

Conference

Conference30th AIAA Applied Aerodynamics Conference 2012
CountryUnited States
CityNew Orleans, LA
Period25/06/1228/06/12

Fingerprint

Flow structure
Flow visualization
Wind tunnels
Drag
Aerodynamics
Vortex flow
Geometry

Cite this

Crouch, T. N., Thompson, M., Burton, D., Sheridan, J., & Brown, N. A. T. (2012). Dominant flow structures in the wake of a cyclist. In 30th AIAA Applied Aerodynamics Conference 2012 (pp. 2022-2031) https://doi.org/10.2514/6.2012-3212
Crouch, Timothy N. ; Thompson, Mark ; Burton, David ; Sheridan, John ; Brown, Nicholas A T. / Dominant flow structures in the wake of a cyclist. 30th AIAA Applied Aerodynamics Conference 2012. 2012. pp. 2022-2031
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Crouch, TN, Thompson, M, Burton, D, Sheridan, J & Brown, NAT 2012, Dominant flow structures in the wake of a cyclist. in 30th AIAA Applied Aerodynamics Conference 2012. pp. 2022-2031, 30th AIAA Applied Aerodynamics Conference 2012, New Orleans, LA, United States, 25/06/12. https://doi.org/10.2514/6.2012-3212

Dominant flow structures in the wake of a cyclist. / Crouch, Timothy N.; Thompson, Mark; Burton, David; Sheridan, John; Brown, Nicholas A T.

30th AIAA Applied Aerodynamics Conference 2012. 2012. p. 2022-2031.

Research output: A Conference proceeding or a Chapter in BookConference contribution

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Crouch TN, Thompson M, Burton D, Sheridan J, Brown NAT. Dominant flow structures in the wake of a cyclist. In 30th AIAA Applied Aerodynamics Conference 2012. 2012. p. 2022-2031 https://doi.org/10.2514/6.2012-3212