The eVOLVE Hybrid Wheel made of metal and plastic, designed for the 2012 MYFord Focus SE, has shown an increase of 1.1 MPG highway in third-party tests, compared to the car's standard production wheel. (Source: Lacks Wheel Trim Systems)
tekochip, one of the things that made me want to write about this wheel design was the fact that in other stories about alternative wheel materials some have commented about how much aerodynamics, as well as less weight from lighter materials, could add up to better performance.
Thanks for weighing in, Chuck. The amount of MPG saved is one of the main things that attracted me to write about this. Also the fact that these guys have done their homework with 3rd-party testing, and at the same facilities, as automotive OEMs.
Excellent Post--I think this is the way highway mileage improvement will occur-in an incremental fashion. I know from previous posts, automotive companies are working on many projects to meet the new Federal guidelines coming quickly. I have been following with great interest materials that are lighter yet as strong as ones now being used. I feel the metal/plastic wheels represent a great breakthrough.
The compromise: reduced cross flow = less cooling of brakes.
On most consumer cars the impact would likely be minimal.
On my car.. well, let's just say I like "spirited" driving on mountain roads.
At "Indy" a number of years ago.... they were noting other trade offs relating to the wheel design. Specifically the affect on handling at high speeds when the wheel was optimized for minimal drag, the wheels would start acting like forward "rudders" during high speed turns - making suspension tuning kinda weird.
While lighter wheels are nice, what I would prefer to see instead is for cars to get rid of all the electric motors for seats, door locks, windows, heat controls, etc.
Manual operations not only weight far less, but are far more reliable and cheaper to maintain. If customers were actually told that things like keyless entry and remote start required leaving radio receivers on all the time, I doubt anyone would actually still want these silly features.
Thanks for covering this, Ann. While power-train and alternative fuel research is well-known and well-covered, I had no idea research into wheels also was being done to boost MPG on automobiles. It's quite interesting to read about and I am consistently impressed by the multifaceted work designers and engineers are doing.
The three-piece modular wheel is even lighter. A 15" dia 10" wide Jongbloed wheel from the mid- '70s weighed 14 lbs. It used two spun aluminum wheel halfs and a forged magnesium center. This was a racing wheel so it was plenty strong but it was difficult to maintain-- dogs would come from adjacent counties to pee on mag wheels!
As far as aerodynamics are concerned, Bonneville racers have used "Moon Discs" since the '50s to improve the rotating and wind resistance of their wheels. These are spun aluminum discs that cover the center of a standard steel wheel. They are still used in land speed racing. They do not allow brake cooling air circulation, however.
Instead of such a complex wheel structure as this new wheel design, why not just mould that design with a carbon fiber reinforced polymer?
Unsprung mass is a big deal for vehicle performance although not necessarily fuel economy. Reduced rotating inertia probably has an impact on city driving more than taking weight out of the seat frames. I wonder how much the plastic is about appearance rather than aerodynamics. Wheels take a beating, and I know they will look pretty bad by the time I buy a 2014 focus in the year 2025.
NIST's new five-year strategic plan for its Material Measurement Laboratory lists additive manufacturing materials development as one of the main areas it will support by developing measurements, data, techniques, and models.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.