Sports Engineering

, Volume 20, Issue 3, pp 231–238 | Cite as

CFD analysis of internal ventilation in high-speed human powered vehicles

  • Paolo BaldisseraEmail author
  • Cristiana Delprete
Original Article


When dealing with fully faired human powered vehicles (HPVs) for speed or endurance record attempts, the need for internal ventilation of the rider arises. Different solutions have been proposed in the literature and in practice by designers and builders of these bicycles. The present paper proposes an analytical approach to design the frontal air inlet according to the VO\(_{2}\)max of the rider in speed competitions. A 3D computational fluid dynamics (CFD) model is presented to analyse the external and internal flow interaction with respect to three design parameters: the presence of wheel covers, the location of the rear vent and its geometry. The CFD results predict that the wheel covers save 23 W of aerodynamic power at 125 km/h. A secondary but significant design parameter is the rear vent position that can provide a further reduction of 11 W at 125 km/h if properly located. Finally, the effect of the rear vent geometry was below the model confidence level, resulting in a likely negligible design parameter.


Human powered vehicles Computational fluid dynamics Internal ventilation Aerodynamic drag 



Computational resources provided by hpc@polito, which is a project of Academic Computing within the Department of Control and Computer Engineering at the Politecnico di Torino ( StarCCM+® licenses were kindly provided by Siemens as official partner of the Policumbent Team educational project.


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Copyright information

© International Sports Engineering Association 2017

Authors and Affiliations

  1. 1.Politecnico di TorinoTurinItaly

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