Blown front wheel hubs back at Williams
Williams sampled blown front wheel hubs on the FW40 last weekend. The Grove-based outfit actually came up first with the concept back in 2013 before ditching it halfway through that season.
The design returned in 2015 at Ferrari, McLaren, and Red Bull, with Force India and Toro Rosso following the trend in 2016. The rationale behind the concept is to deflect part of the airflow usually captured by the brake ducts before the energised flow is blown through the open wheel hub (as a result of the Venturi effect).
The high-pressure air that is blown through the open wheel hub helps prevent airflow separation, while also pushing away the dirty wake disrupting the air underneath the car. The blown front wheel hub concept does require compromise though, as it still creates some drag.
To what end? Well, when ambient airflow encounters a rotating wheel, several phenomena happen, including airflow separation from the tyre’s surface. This creates areas of low-pressure and turbulent air both above and around the wheel. This dirty wake, known as ‘tyre squirt’, generates drag but also upsets the airflow underneath the car as well as at the rear.
What’s more, Williams also tweaked its front wing, adding a vane to one of the flaps, while also making the winglet on the endplate longer.
