Approach for controlling exhaust gas recirculation
AssigneeFord Global Technologies, LLC
InventorsJianwen James Yi, Steven Wooldridge, Brad Alan VanDerWege, Shiyou Yang, Thomas A. McCarthy
Life of this patent
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Abstract
Various embodiments related to controlling EGR in an engine are disclosed. In one embodiment, a first EGR amount is supplied to a cylinder at a first temperature and a first engine speed and load. Further, at the first engine speed and load, as engine temperature increases from the first temperature to a second temperature, a first fuel amount is injected after exhaust valve closing and before intake valve opening while a second EGR amount is supplied to the cylinder that is greater than the first EGR amount.
Claims22
A method comprising:
- at a first temperature and a first engine speed and load, supplying a first EGR amount to a cylinder;
- and
- at the first engine speed and load, responsive to engine temperature increasing to a second temperature, injecting a first fuel amount after exhaust valve closing and before intake valve opening and supplying a second EGR amount to the cylinder greater than the first EGR amount after intake valve opening.
An engine system comprising:
- a cylinder coupled to an engine intake and an engine exhaust;
- a fuel injector configured to directly inject fuel into the cylinder;
- an EGR system for recirculating an amount of exhaust gas from the engine exhaust to the engine intake;
- and
- a controller including a processor and computer readable medium holding instruction that when executed by the processor:
- at a first engine temperature and a first engine speed and load, supply a first EGR amount after intake valve opening to the cylinder via the EGR system;
- and
- at the first engine speed and load, responsive to engine temperature increasing from the first engine temperature to a second engine temperature, inject a first fuel amount after exhaust valve closing and before intake valve opening via the fuel injector while supplying a second EGR amount to the cylinder that is greater than the first EGR amount after intake valve opening via the EGR system.
A method comprising:
- at a first engine temperature, injecting a first fuel amount to a cylinder after intake valve opening while supplying a first EGR amount to the cylinder;
- and
- at a second engine temperature that is greater than the first engine temperature, injecting a second fuel amount to the cylinder after exhaust valve closing and before intake valve opening, and injecting a third fuel amount to the cylinder after intake valve opening while supplying a second EGR amount to the cylinder that is greater than the first EGR amount, the first EGR amount and second EGR amount supplied to the cylinder from an exhaust passage to an intake passage via an EGR passage.
A method, comprising:
- for a given condition at a lower temperature, operating with a lower EGR amount and a single direct fuel injection commencing after intake valve opening during an intake stroke;
- and
- for the given condition at a higher temperature, operating with a higher EGR amount, a first direct fuel injection commencing after exhaust valve closure but before intake valve opening, and a second direct fuel injection commencing after the intake valve opening, where the given condition is a given engine speed and load and where the lower EGR amount and higher EGR amount are supplied from an exhaust passage to an intake passage via an EGR passage.
Dependencies are inferred from the claim text.