Design of a front aerodynamic package : final design report
Aerodynamic devices are utilized in higher levels of motorsport such as Formula-1 to increase the traction of the tires by generating down force. This increase in traction increases the performance envelope of the race car since cornering can be performed at higher speeds without a loss of control. However, the aerodynamic device that provides the down force also increases drag. The additional drag is especially detrimental on straight sections of the track. As higher speeds are attained, the increased drag leads to a decrease in lap-times and the drive force required is increased. An ideal solution is a dynamically adjustable aerodynamic device which offers the ability to change the relative amount of down force and drag. Such devices have been used in many forms of motorsport in the past. The Society of Automotive Engineers (SAE) Collegiate Design Series is an engineering competition wherein university students compete in the design, building and racing of an open-wheel race car. The Formula Electric team has requested a design of an adjustable aerodynamic device. The device is to be mounted to the front of the vehicle such that the wing mount is integrated into the carbon fibre monocoque. Furthermore, the nose cone is to be designed such that there is absolutely no lift experienced by it. The dimensions of the vehicle were provided. The goal of the design is to decrease the team’s lap times during the autocross event at the SAE competition. In this report, the details of the design are presented. When the car is on a straight away, the device positions itself such that it has minimal detrimental aerodynamic effect, as requested by the client. During cornering, the functional position is assumed, which creates down force. The variable down force is accomplished by an active wing section that was optimized to create as much down force as possible given that the car would be banking a turn at approximately 50 km/h. In addition to the active wing, another wing section is fixed in close proximity to the ground. The bottom wing accomplishes several tasks. Firstly, it is used as a structural member supporting the endplates to which the active wing is mounted. Secondly, it houses the actuators and microcontroller responsible for the adjustment of the active wing. The developed design was used in a simulation of the current SAE Electric race car. At a representative speed of 50 km/h, the use of the active front wing was found to improve steady state cornering by 6% to 1.89g (active wing @ 13°). Alternatively, the car’s straight-line braking could be improved by 8% to 2.04g (active wing @ 28°). With the wing in the low-drag position (active wing @ +6°), the additional power requirement is only 19.45W.
design, front, aerodynamic, package