SLICK SOLUTIONS FOR friction reduction

Suppliers and engine designers are attacking every potential source of internal friction-no longer a “low-hanging fruit”-as the battle to squeeze more mechanical work from less fuel intensifies.

Reducing internal friction has always been a priority of powertrain designers, but recently the subject has taken on greater urgency in the crunch to meet tough new global CO₂ regulations. In piston engines, friction loss rises with the square of rpm, which is one reason OEMs are “downspeeding” their new engine families. And with their key suppliers, they're digging deeper to find cost-effective solutions to this century-old challenge-from “rollerizing” camshafts to optimizing lubrication schemes, to new gas-cushion shaft seals, to decoupling front-end drive systems. New materials and surface coatings are also enablers.

“We looked across the entire propulsion system to find places we could reduce spin and drag losses and minimize internal friction,” said Tim Grewe, GM's General Director of Vehicle Electrification, speaking to Automotive Engineering about the 2016 Chevrolet Volt. “This is a major area of focus in vehicle development at GM and the industry going forward.”