A system for controlling the temperature of a particulate filter coupled to an exhaust outlet of an internal combustion engine includes a controller responsive to volumetric flow and temperature of exhaust gas to determine a filter regeneration parameter. In a hybrid electric-engine vehicle application, various control strategies are implemented as a function of the regeneration parameter to control exhaust gas temperature suitably for proper regeneration of the particulate filter. Such strategies include shifting the duty cycle of the engine toward lower engine speed operation along lines of constant power output, modifying the ratio of electrical power and engine power and controlling recharging of the battery supplying electrical energy to the vehicle's electric drive motor under vehicle deceleration conditions. In vehicle applications including a transmission coupled directly to the engine, shift points of the transmission are modified as a function of the regeneration parameter to control exhaust gas temperature.

System for controlling particulate filter temperature

A diesel engine exhaust particulate trap and regeneration system for trapping of particulates in the engine gases and periodic burning thereof is disclosed. Collected particulates are burned in the trap by increasing the trap temperature utilizing a backpressure valve in the exhaust gas line. A microprocessor, which receives engine operating parameters via sensors, compares the sensed parameter valves to engine maps stored in its memory and opens or closes the valve via an actuator in response thereto.

Diesel engine particulate trap regeneration system

A regeneration system for a particulate trap (2) provided in an exhaust pipe (1a) of an engine in which the regeneration is initiated when the pressure loss across the trap (2) has reached a preset value Then the preset value is renewed when the peak value of the trap temperature through the regeneration resides out of a predetermined range or when the pressure loss after the regeneration exceeds the preset value even though the peak value resides within said predetermined range The initial value of said preset value is determined on the basis of the minimum value within the variation of the pressure loss of cleaned traps

Regeneration system for particulate trap

A method and system for reducing pollutant concentration within an internal combustion engine exhaust stream is disclosed. Soot and products of incomplete combustion in the engine exhaust stream are destroyed by oxidizing them in a flameless thermal oxidizer that contains a matrix of heat-resistant media. Methods and systems for increasing particle residence time within the thermal oxidizer are also disclosed. These techniques include employing electrostatic precipitation, centrifugal force, and particle impaction sections. A method and system for reducing oxides of nitrogen (NOx) emissions is also disclosed. Low NOx concentration may be obtained by adding a SCR system after a thermal oxidizer, by tuning the engine to produce low NOx/high soot and destroying the soot in a thermal oxidizer, and by injecting a reductant into the thermal oxidizer. The flameless thermal oxidizer may be located between the engine and a turbo-charger to enhance thermal efficiency and to reduce turbo-charger wear. The thermal oxidizer comprises longitudinal and radial flow systems, which each may include a reaction wave of the following shapes: planar, cylindrical, Bunsen, Burke-Schumann, and an inverted V. An engineered matrix is disclosed to manipulate the shape of the reaction zone.

Method of reducing internal combustion engine emissions, and system for same

A matrix bed is disclosed in which a non-planar reaction wave front is formed during operation. This is accomplished by heating the matrix bed, containing heat-resistant material, until at least a reaction portion of the matrix bed is above the temperature required for a plurality of reactant gas streams to react. Next, the reactant gas streams are directed through the matrix bed in a manner so as to form at least a Bunsen, Burke-Schumann, inverted-V, or some other type of non-planar reaction wave front at the portion of the matrix bed that is heated above the reactant gas streams reaction temperature. At the non-planar reaction wave front, the reactant gas streams react to produce a reaction product gas stream that is then exhausted from the matrix bed.

Matrix bed for generating non-planar reaction wave fronts, and method thereof

An apparatus for controlling the supply of air to a burner used to recombust diesel particulates trapped in a ceramic filter. The inventive control apparatus includes an exhaust bypass line that bypasses the filter, an air supply line leading to a burner associated with the filter, a flow control valve that adjusts the cross-sectional area for the air flow in the air supply line, a relief valve that maintains a constant difference between pressures at points upstream and downstream of the flow control valve, and a control unit that controls the degree of opening of the flow control valve. With the invention, precise control over the flow rate of secondary air is ensured.

Regenerator for diesel particulate filter

A diesel particulate filter system for treating the exhaust gas of a diesel engine which is small in size and inexpensive. The system includes a particulate filter connected in a gas line from the engine, a burner, including an ignition plug, connected at a point upstream of the particulate filter and which is supplied with fuel, a primary air flow for atomizing the fuel, and a secondary air flow for burning the particulates trapped in the particular filter and which supplies the particulate filter with a hot burning gas produced by the ignition plug. Primary and secondary pumps supply, respectively, the primary and secondary air flows. A single motor drives both the primary and secondary air pumps. The ignition plug and motor are controlled so that when the amount of particulates trapped in the filter exceeds a preset level, the ignition plug and motor are activated to clean the filter by burning the particulates in the burner.

Diesel particulate filter system

A particulate removing device comprises a regenerating burner connected via an interrupting valve to a mixer subsequently connected to a particulate filter. The interrupting valve may be disposed in a housing for the burner on that end portion connected to the mixer through an exit to open and close the exit. When the burner generates a combustion gas, the valve opens the exit to permit the combustion gas to enter the mixer where it is mixed with an exhaust gas from a Diesel engine. The mixed gas heats and regenerates the particulate filter. When the burner is not used, the valve closes the exit to prevent the exhaust gas from the mixer from partly entering the burners housing. Alternatively, the interrupting valve may be disposed in a housing for the mixer on that end portion connected to the burner's housing through an exit to open and close the inlet.

Kiyoichi Shinsei

Papers

Regenerator for diesel particulate filter

Diesel particulate filter system

Device for removing particulates in exhaust gas