The CRONUZ was developed from a blank page to fulfil best-in-class aerodynamic values thanks to the seamless cooperation between Applus IDIADA’s aerodynamicists and designers. That cooperation allowed the upper-body to be optimized while keeping the design concepts. This concept car includes breakthrough aerodynamic solutions that include active and passive aerodynamic enablers that focus on key areas such as the wheelhouses and underbody.
CRONUZ technical specifications
- Compact electric SUV (C class)
- 1 electric motor per axle
- 4 seats
- Lightweight BiW: 200 kg
- Dimensions: 4,415 x 1,819 x 1,536 mm
- Skateboard battery pack platform: 200L
- Wheelbase: 2,720 mm
- Closed under-hood with active grill shutter
- Ground clearance: 177 mm
- Rear view cameras
- Low-friction high-efficiency 195/55/R20 tyres
- Intelligent light system
Aerodynamics innovations within the CRONUZ Project
Active systems: various rocker and fairings were investigated achieving a potential improvement of 11 drag counts. This force reduction is achieved mainly by reducing forces on the wheels, and increased base pressure via reduced wake intensity. Assuming that the rocker and front fairing could break the design line, we decided to develop active systems for these parts
Wheelhouse & underbody: The wheelwell areas and underbody are responsible for 40% of the aerodynamic losses and therefore have high potential for improvement. Design actions in this area include optimized rims and underbody wheelhouse covers that interact perfectly with the extended rockers and front fairings to minimize the wheel house air circulation. The effect of the wheelhouse covers and the rims makes a 44 drag count reduction possible
CRONUZ Design features
The objective of the designing team was to create a minimalist aero design concept to achieve a pure and elegant form with surface and volume solutions to reach a Cx below 0.2. These are the main design features:
- Emotional surfaces
- Streamlined design form
- Steering laser headlamps
- Progressive brightness OLED stop lights
- Dynamics active cooling system/grille
- Driving integrated mirror camera
Final assessment in wind tunnel
The full-scale model was used for testing the vehicle configurations and enablers with better CFD performance, as well as confirming the accuracy of the CFD aerodynamic forces. The best performing vehicle configuration provided a Cx value of 0.19.
Detailed flow measurement in the wake to validate the simulation set-up, including mesh discretization, turbulence modelling and wind tunnel representation were also performed.