VDE_Accepted.pdf (1.93 MB)
Download fileImpact and observations of cylinder deactivation and reactivation in a downsized gasoline turbocharged direct injection engine
journal contribution
posted on 2019-10-08, 08:31 authored by Matthew Parker, Changzhao Jiang, Daniel ButcherDaniel Butcher, Adrian SpencerAdrian Spencer, Colin GarnerColin Garner, Dennis WittCylinder deactivation, sometimes referred to as Variable Displacement Engine (VDE)
technology, is a method being employed in state-of-the-art reciprocating engines to
improve fuel economy. The approach involves disabling the valve actuation of one or more
cylinders to deactivate them, thus forcing the engine to operate at a higher specific load
across the remaining cylinders to produce the torque demanded. Operating at such a point
with an increased throttle opening reduces the engine’s pumping losses and hence reduces
fuel consumption. In this work, the spray morphology, combustion and emissions of a
three-cylinder downsized gasoline turbocharged direct injection (GTDI) engine with VDE
capability on one cylinder were studied. This investigation allowed the interaction between
the fuel spray, engine performance and emissions immediately following the reactivation
of the deactivated cylinder to be better understood. Three operation modes were examined
which included running the engine at full displacement, at the reduced displacement and at
full displacement with increased indicated mean effective pressure (IMEP), matching that
of the reduced displacement mode. The study showed that cylinder deactivation
significantly reduced specific fuel consumption at the conditions tested in comparison to
full displacement operation. It was also found that when running the engine at full
displacement but with the reduced displacement level IMEP, the specific fuel consumption
was greater than for reduced displacement operation. In addition, it was observed that
particulate number (PN) emissions increase transiently during the deactivation period due
the disturbances to the fuelling control caused by displacement transitions. Improved
fuelling control, refinement of the engine calibration during reduced displacement
operation or a Gasoline Particulate Filter (GPF) could be used to manage this PN level.
Funding
TSB/APC project number 101891
History
School
- Aeronautical, Automotive, Chemical and Materials Engineering
Department
- Aeronautical and Automotive Engineering