In advance of the market launch of the highly anticipated next generation NSX, the engineers leading the supercar’s development shared new technical details and design strategies with the automotive engineering community at the SAE 2015 World Congress and Exhibition. Additional information about the team’s efforts to achieve a true “New Sports Experience” included details of the NSX’s world’s first body construction process that helped create a multi-material space frame resulting in class-leading body rigidity, the advanced total airflow management system and an update on NSX’s power unit specifications.
Ted Klaus, chief engineer and global development leader of the new NSX, introduced key powertrain, body and dynamic performance engineers who shared new product and technical details in their related areas of the development. The unprecedented sharing of technical details prior to the car’s market introduction reflects the desire of the NSX development team and the company to inspire the imagination of automotive and technology enthusiasts along with the next generation of engineers.
“Our goal is to create something altogether new and exciting, something that advances the concept of a next generation supercar in the spirit of the original NSX,” said Klaus. “In order to provide NSX-level value, we needed to push ourselves to experiment with, refine and then realize many new technologies.”
Significant technical revelations concerning the NSX included:
Additional details on each of these engineering achievements follow:
Acura’s First Application of a Multi-Material Body with Space Frame Construction
Developing the Most Rigid-in-Class, Multi-Material Body
At the core of the NSX mission to deliver timeless sports car values is an aluminium intensive, multi-material space frame. This innovative space frame represents a next-generation leap in body design with class-leading technology that is exclusive to Honda within the automotive market. Based on internal data, the all-new NSX multi-material body is by far the most rigid in its competitive set.
While the all-aluminium monocoque body of the original NSX was ahead of its time, current aluminium and ultra high strength steel intensive body architecture has been taken to the limit for supercar design.
“For this new NSX development, anything and everything that could offer incredible base rigidity and lightweight design was on the table,” said Shawn Tarr, principal engineer and NSX body development leader. “We considered an all-aluminium unibody, carbon fibre monocoque and space frame designs and ultimately engineered a multi-material space frame because it offers the lowest weight and best rigidity, precision and hybrid powertrain packaging capability of any design.”
A key advancement in casting technology allowed the NSX development team to realise a quantum leap in body design, for the first time being able to engineer a vehicle with castings in key locations for rigidity, that also support the ductility necessary for placement within crush zones.
World’s First Application of Ablation Casting
The NSX heralds the world’s first application of ablation casting technology in the automotive industry. Ablation casting combines traditional casting methods with rapid cooling techniques to offer the design flexibility and rigidity of casting with the ductility and energy absorption characteristics of extruded material.
Traditional castings provide the ultimate rigidity in space frame and other body designs, but have traditionally suffered a major drawback: traditional castings are brittle. With the no-compromise performance goals of the NSX, a groundbreaking new casting method within the crush zones had to be used.
New A-Pillar Construction Technique
In addition to the world’s first casting technology, the NSX applies an all-new three-dimensionally formed ultra high strength steel A-pillar that provides next-generation rigidity and precise shape specification tolerances.
The previous generation NSX had a thin A-pillar that provided very good outward visibility. Reflecting this heritage with modern rigidity and roof crush performance requirements demanded this new, ultra high strength production method.
Advanced Materials Strategy
NSX represents an advanced expression of modern body design theory: the strategic integration of multiple materials to achieve optimal body performance for numerous targets, including rigidity, dynamic response, superior fit and finish and occupant protection.
Total Airflow Management
Engineering a Next Generation Thermal and Aerodynamic Package via
Total Airflow Management
To meet the challenge of the ambitious performance targets, radical packaging design and exotic styling for the next generation NSX, the development team had to totally re-imagine the thermal and aerodynamic engineering for this modern supercar so that maximum energy is extracted from the flow of air around and through the NSX with the highest efficiency.
This new total airflow management strategy supports component cooling, aerodynamic performance (drag and downforce) at a very high level without the use of active aero technology, while also contributing to even more dynamic styling.
Computational fluid dynamics (CFD) was used extensively during development to allow the U.S. based development team to maximise the performance of a power unit being developed in Japan. CFD models were run on computers totalling many years’ worth of computational uptime.
Thermal CFD was effectively used in two ways during development, first for the proof-of-concept in establishing heat management strategy at the earliest development stage and second, for continuous thermal performance improvement as the vehicle matured through development. Extensive involvement of thermal CFD with design engineers during the development enabled maximum design optimization.
Along with the use of advanced CFD, wind tunnel and real world testing, the development team also employed computerised lap-time simulation models of some of the world’s most legendary proving grounds that could then be run on chassis-dynamometers allowing testing and validation of computer models for thermal management.
NSX achieves top-class aerodynamic balance and supercar aerodynamic downforce without the use of active aero. Aerodynamic drag is minimised, even while moving large airflows through NSX as it inhales and exhales. Aerodynamic downforce is created through the total airflow management focus on utilising airflow through each vent, as NSX exhales, and through more traditional aerodynamic shape optimisation.
NSX has undergone extensive testing at the company's state-of-the-art wind tunnel in Raymond, Ohio, using ultra-detailed 40-percent-scale models that replicate the entire intake and exhaust vents, heat exchangers and major under-hood components. These highly accurate scale models replicate drag and lift performance with near perfect approximation. It has been verified and put through its paces at the company’s full-scale wind tunnel in Japan, and on real and simulated proving grounds throughout the world.
Total airflow management vents and precision ducting also help create strong, consistent downforce for NSX and were tuned to optimised forms with aerodynamicist and designer input during working wind tunnel sessions.
Sport Hybrid Super Handling All-Wheel Drive
A new handling paradigm decades in the making
The groundbreaking Sport Hybrid SH-AWD dynamic torque vectoring technology applied to the all-new NSX represents research and development that has been ongoing for well over two decades.
Next-generation torque vectoring
Honda has been continuously refining its advanced torque vectoring technology while in parallel developing new ways of accomplishing the timeless sports car values of lightweight, rigid chassis and potent powerplants. This all-new Sport Hybrid SH-AWD represents a system injected with more electric power, delivered more directly, managing more internal combustion power than any system Acura has engineered to date.
In keeping with the development team’s ‘human- centred supercar’ concept, the new NSX and its Sport Hybrid Super Handling drivetrain were truly engineered from the driver out. While the NSX provides a new sports experience with ‘on rails handling,’ its Super Handling technology was optimised to enhance the driving experience by responding instantaneously and intuitively to the will of the driver.
Sport-Hybrid SH-AWD Power Unit
Powering the Sport Hybrid Power Unit with Racing Technologies
As announced at the 2015 North American International Auto Show, the new NSX will utilise an all-new power unit from a clean sheet design. At its heart is an all-new longitudinally mounted twin-turbo V6 engine that is mated to an all-new, Honda developed 9-speed DCT with an electric motor that applies its torque directly to the crankshaft for higher output with immediate power delivery to the rear wheels.
The all-new NSX represents the convergence of timeless sports car values and advanced technology in a pinnacle supercar. Timeless sports car values include classic goals like a rigid and light chassis with the mass placed low and close to the driver. Advanced technologies include those that enhance the driving experience in new ways.
To bring back the legendary NSX the global development team has innovated in the critical, timeless areas of frame and aerodynamics in addition to tirelessly refining its key advanced technology - the state-of-the-art hybrid power unit. The NSX has many innovative components, but the basic recipe is simple: timeless sports car values blended perfectly with advanced technologies that deliver a new sports experience.
1Ablation casting is co-developed for this world’s first automotive application with the original inventor of the process, Alotech Limited.