Abstract:
An exhaust gas recirculation system adapted for use by an internal combustion engine, and for selectively diverting a recirculated portion of the engine exhaust away from the EGR cooler, includes a by-pass conduit and/or feed line shiftable between open and closed conditions, and an active material actuator.
Abstract:
A heat exchanger of motor vehicle processes a gas flow including combustion exhaust gas. Combustion by-product deposit build-up within the heat exchanger is reduced by maintaining a minimum gas flow velocity within the heat exchanger by reducing heat exchanger total gas flow cross section to locally increase a gas flow velocity.
Abstract:
The invention comprises a method to operate a direct-injection engine operative at various air/fuel ratios. The method comprises monitoring in-cylinder pressure, along with a corresponding engine crank position to periodically to determine instantaneous in-cylinder pressure states corresponding to the engine crank position during compression and expansion. Pressure ratios are determined based upon the instantaneous in-cylinder pressure states. A combustion heat release is determined based upon the pressure ratios. An aspect of the invention comprises extending the operation to diesel, diesel premixed and to HCCI engines.
Abstract:
A method for operating an internal combustion engine configured to operate lean of stoichiometry includes reducing temperature of a portion of an exhaust gas feedstream recirculated to an intake system of the engine, and reducing mass flowrate of particulate matter and hydrocarbons borne in the recirculated portion of the exhaust gas feedstream upstream of the heat exchanger effective to reduce deposition of particulate matter and hydrocarbons onto and adhesion to surface areas of the heat exchanger.
Abstract:
An internal combustion engine is equipped with an EGR system that includes an EGR heat exchanger. A method for monitoring the EGR heat exchanger includes monitoring an EGR gas inlet temperature to the EGR heat exchanger, an EGR gas outlet temperature from the EGR heat exchanger, a coolant temperature and a mass EGR flowrate through the EGR heat exchanger for a present engine operating point. An actual thermal effectiveness of the EGR heat exchanger for the present engine operating point is determined. A maximum heat transfer coefficient for the EGR side of the EGR heat exchanger is determined for the present engine operating point. The EGR heat exchanger is regenerated when the actual heat transfer coefficient differs from the maximum heat transfer coefficient for the present engine operating point.
Abstract:
A spark plug includes a center electrode substantially aligned with a longitudinal first axis and a surface-gap ground electrode radially aligned with the center electrode along a surface-gap electrode second axis substantially orthogonal to the longitudinal first axis and passing therethrough. The center electrode and the surface-gap ground electrode define a radial spark gap therebetween. The spark plug further includes a J-gap ground electrode radially aligned with the center electrode. The center electrode and the J-gap ground electrode define an axial spark gap therebetween. The J-gap ground electrode radial alignment has an angular separation from the surface-gap electrode second axis of no greater than about 30 degrees.
Abstract:
An internal combustion engine is configured with combustion chamber pressure sensing and exhaust gas recirculation apparatus. Fuel injection timing is adjusted based on combustion phasing and exhaust gas recirculation is controlled based on average fuel injection timing adjustments.
Abstract:
A method for operating an internal combustion engine configured to operate lean of stoichiometry includes reducing temperature of a portion of an exhaust gas feedstream recirculated to an intake system of the engine, and reducing mass flowrate of particulate matter and hydrocarbons borne in the recirculated portion of the exhaust gas feedstream upstream of the heat exchanger effective to reduce deposition of particulate matter and hydrocarbons onto and adhesion to surface areas of the heat exchanger.
Abstract:
A method for controlling operation of an internal combustion engine operating lean of stoichiometry is described. The engine is a multi-cylinder direct-injection engine operative in repetitive cycles each cycle including intake, compression, expansion, and exhaust strokes. The method includes adapting a plurality of fuel injectors to directly inject a first and a second mass of fuel into the cylinders during each cycle. Pressure sensing devices monitor in-cylinder pressure in the cylinders during ongoing operation. The first mass of fuel is injected into one of the cylinders. A cylinder pressure ratio is determined in the cylinder subsequent to injecting the first mass of fuel based upon the monitored pressure. The first mass of fuel injected is adjusted during a subsequent cycle based upon the cylinder pressure ratio.
Abstract:
A heat exchanger of motor vehicle processes a gas flow including combustion exhaust gas. Combustion by-product deposit build-up within the heat exchanger is reduced by maintaining a minimum gas flow velocity within the heat exchanger by reducing heat exchanger total gas flow cross section to locally increase a gas flow velocity.