When it comes to performance, you have 3 options, increase power, reduce weight, or reduce drag. The latest NSX is going to focus a lot on the third, leveraging F1-style engineering to create a system Honda are calling ‘total airflow management’. This concept is designed to achieve superior levels of downforce, minimise drag and enhance grip, stability and balance.
NSX Aerodynamics and Cooling Project Leader, Thomas Ramsey is responsible for the new concept that leverages computational fluid dynamic (CFD) simulations and testing of 40 per cent scale models in Honda’s advanced wind tunnel facility in Ohio.
In many ways, with the design of the all-new Honda NSX, you literally have form following function, so this was a really exciting vehicle to work on as an aerodynamicist.
To meet the challenge of the ambitious performance targets, innovative packaging design and dramatic styling, Honda’s engineers had to totally re-imagine the exterior engineering for this modern supercar.
This new ‘total airflow management’ strategy supports component cooling and aerodynamic performance while also contributing to even more dynamic styling.
When creating a supercar, Honda is leveraging every trick possible to extract maximum benefit from the flow of air around the all-new NSX. By directing the airflow through the front of the car is guided through the front bar to cool the brakes while it also slides effortlessly over the hood to push the car to the ground.
As the air flows down the side of the car, its sucked into rear intakes to cool the rear brakes and up over the hips of the car to provide further rear grip, on top of the mechanical grip available from the rear tyres.
Surfaces, intake grilles and exhaust vents are shaped and proportioned to reduce aerodynamic drag, create downforce, maximise cooling and efficiently dissipate unwanted heat. The analysis was verified at Honda’s full-scale, moving ground plane wind tunnel in Tochigi, Japan.
Balancing downforce for optimal performance
The front-to-rear balance of downforce generated by the NSX’s exterior design was carefully tuned. An exhaustive research and development programme determined that generating approximately 3x the downforce at the rear relative as the front, would provide the optimal downforce distribution for high-performance and day-to-day driving.
A rear diffuser works together with the rear spoiler and taillight slots to generate significant downforce and manage effectively the drag created by the aerodynamic wake generated behind the car. The NSX’s high level of downforce is accomplished without the need for active aerodynamic bodywork or other devices.
The airflow through the car’s front-end follows carefully optimised exit paths, which take into consideration total airflow, maximum downforce and a low coefficient of drag. This air is then deliberately manipulated when exiting in order to achieve a pre-determined downstream flow pattern to feed the mid-engine air inlets.
Vents specifically positioned to reduce turbulence and aerodynamic loss around the front wheels work in conjunction with front wing vents to stabilise airflow down the side of the car. These vents combine with the floating C-pillars to provide airflow to the signature side intakes, channelling it into the engine intake, engine bay, and turbo intercoolers. The side intakes are also designed to direct airflow over the rear deck to increase downforce.
The NSX’s exterior design also provides highly efficient thermal management required by its hybrid powertrain. There are seven different primary heat sources – the 3.5-litre V6 engine, two turbochargers, the nine-speed Dual Clutch Transmission (DCT), the Power Distribution Unit and the two motors within the Twin Motor Unit. To provide efficient cooling to each of these elements, airflow is managed through 10 different heat exchangers.
Openings at the front of the vehicle supply cooling airflow across the key heat exchangers located within the front section – front engine radiators, twin motor unit cooler, condenser, transmission gear cooler and hybrid Power Distribution Unit. Air flowing over the roof and down the rear hatch glass is captured to feed the transmission clutch cooler and further facilitate engine bay cooling.
Check out the video below to see the ‘total airflow management’ concept in action.