The greatest obstacle in the acceleration of a car through air is aerodynamic drag. With this increased drag is the expenditure of fuel. About 50-60% of a vehicles’ total fuel energy is lost to overcome adverse aerodynamic forces. However, with the increase of fuel prices, many solutions have surfaced. One of these solutions are the implementation of camera modules to replace bulky traditional side mirrors. For this report, a thorough analysis was conducted into the aerodynamic benefits of these newly proposed camera modules in comparison to the conventional solid state mirrors. Specifically, one conventional side mirror along with two newly proposed camera module’s were studied in this thesis report.
For this analysis, the overall drag of each module was found using CFD simulation under turbulent conditions at 60 km/h using the Realized K- method. The drag and Cd values found for the conventional side mirror were 3.985 N and 0.38 respectively. The values found for the two camera modules, Models B and C, were 0.526 N and 0.857 N. Their Cd values were found to be 0.312 and 0.365. This shows a potential of the drag reduction of the side mirror by almost 87% if the switch was made to the newer technology. This value also agreed with the prediction by Honda on their technology which has stated a possible drag reduction for this part by up to 90%.
However, when observing the bigger picture, it became evident that although this drag reduction is significant for locally, it simply is not enough to make a big impact on the drag reduction of the entire vehicle. With a maximum decrease in the total vehicle drag found to to be only 4%, the reduction in the fuel consumption of the vehicle would only decrease by 0.2 gallons per mile. On the other hand, improvements in parts such as the car rims or the underbelly of the car can result in fuel improvements of upwards of 12%-25%. For this reason, it can be concluded that automobile manufacturers research other possible solutions to reduce the vehicle drag such as with the redesign of the underbelly of the car or wheel arches and rims.