Horst Schulte, Martin Wirth
Ford Motor Company
Future internal combustion engines for light duty applications will have to cope with a very complex set of customer, legal and business requirements. Customers are expecting further improvements in durability, reliability, drivability, fuel economy, and cost of ownership. Legal requirements are focused on significant emission and fuel consumption reductions. Additional manufacturing cost reductions will be essential to maintain, or better grow the business in a very competitive environment.
The challenge for the diesel engine will be to meet the future emission standards at affordable cost, while maintaining its fuel economy advantages. Regarding the emissions, advanced diesel technologies will have to focus mainly on NOx reduction. New combustion system concepts in combination with advanced airhandling/boosting and control systems offer a promising potential.
The focus for future gasoline engine development will be on fuel economy improvements through improved combustion systems and reduced throttle losses at part load operation. This can be achieved through e.g. direct fuel injection with stratified lean part load operation. Downsizing in combination with boosting offers an additional potential. Internal combustion engines still have a huge potential to deal with the challenges of the future. In comparison with alternative powertrain concepts, at least for the next 20 years, the internal combustion engine should be able to maintain its advantages regarding high power density, low manufacturing cost, recyclability, long driving distance between two refueling events, well established fuel supply infrastructure, and its capability to use a wide variety of fuels. Key-words: Diesel and Gasoline Engines, Fuel Economy, Emissions, Combustion, Boosting INTRODUCTION
Future powertrains for light duty applications have to fulfil a very complex set of requirements (Figure 1), and there is always the question: "Will the internal combustion engine be able to cope with these challenges also in the future?" Price
More Features and Equipment
Market Share /Total Volume
Product Variety (Niche
Fuel Consumption / CO2
(ACEA / CAFÉ)
Figure 1: Interaction between Customer Expectations, Environmental/Legal Requirements and Business Aspects Regarding customer expectations, trends are very
similar for gasoline and diesel engines, especially in the
volume segments and markets. Customers are very
focused on total cost of ownership, which is determined
by such factors as price, resale value, fuel consumption
(and fuel price), maintenance cost, as well as reliability
and durability. At the same time, customer expectations
regarding "fun to drive" are still increasing. This
translates into a continuation of the "power and torque
race" to further improve vehicle performance and
drivability (Figure 2).
1990 1995 2000 2005 2010
Specific Power [kW/ltr.]
Figure 2: Development of Specific Power of Gasoline
and Diesel Engines
Advanced boosting technologies will play a major role
to further increase specific power and torque. In this
context, turbocharging will maintain it's dominant role.
In addition to performance improvements, at steadily
rising fuel prices, customers are expecting further
improvements in fuel economy and comfort (NVH) in
bigger (heavier) vehicles with more features and
equipment. Another set of conflicting...