25-09-2010, 12:46 PM
ABSTRACT
Future internal combustion engines for light duty applications will have to cope with a very complex set of customer, legal and business requirements. durability, reliability, drivability, fuel economy, and cost of ownership etc are the digfferent area where the customers would like improvements. DIesel engines will have to cater to future emission standards at affordable cost. airhandling/boosting and control system are the focus areas. fuel economy improvements through improved combustion
systems will be the focus for petrol engines. high power density, low manufacturing cost, recyclability etc should be maintained while reducing the emissions.
THE DIESEL EMISSIONS CHALLENGE
These kind of engiens must cop up with future emission targets at affordable cost. Euro Stage 4 standard must be met the next year itself. NOx and particulate matter (PM) standards must be particularly focussed while keeping an eye on CO and HC too.
LOW NOx DIESEL COMBUSTION
HCCI, pHCCI, UNIBUS, PREDIC, MK, NADI, ACCP, HCLI, HCDC etc are the various low NOx diesel combustion processes. These are low temperature combustion (LTC) processes and they have high EGR rates so that bulk temperature of the cylinder charge can be limited. a boosting/airhandling/ EGR system that effectively provides the right mixture out of boost pressure and EGR rate under all load and speed
conditions is an essential component for maintaining low temperature combustion.
Diesel exhaust after treatment
Lean NOx traps and selective catalytic reduction must be focussed upon. However the SCR has the most potential as it has a higher NOx reduction potential because of its
wider temperature window with high conversion rates
Full report:
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