The Range Rover Evoque is a compact luxury SUV, first introduced by Land Rover in 2012. Almost 800,000 units of the first-generation vehicle were sold. This paper explores some of the challenges entailed in developing the next generation of this successful product, maintaining key design cues while at the same time improving its aerodynamic efficiency.
A development approach is outlined that made use of both numerical simulation and full-scale moving ground wind tunnel testing. A drag coefficient of 0.32 was obtained for the best derivative by paying particular attention to:
the integration of active grille shutters;
the front bumper and tyre package;
brake cooling;
underfloor design;
wake control strategy; and
detail optimization.
This approach delivered the most aerodynamic Range Rover at the time of its introduction. The impact of these design changes on the aerodynamic flow field and consequently drag is highlighted. An interaction between front wheel deflectors and different tyres of the same nominal dimensions is explored over a range of small yaw angles, illustrating the need to develop vehicles using a range of boundary conditions. In addition, a relationship is shown between wake state defined in terms of the vertical pressure gradient and reduced aerodynamic drag.
Finally, changes in regulations governing the assessment of emissions and fuel economy are driving a need for vehicle manufacturers to go beyond the traditional focus on the drag of the best vehicle derivative and manage the spread of values arising from customers’ choice of powertrain, wheel and tyre fitment along with exterior trim options. For this vehicle, we highlight that the average drag coefficient for sales in the European market over a year was 15% lower than the outgoing car, showing that improved aerodynamic efficiency has actually been delivered to customers.
