Exhaust gas recirculation systems with variable venturi devices
AssigneeCummins Inc.
InventorRajkumar Subramanian
Life of this patent
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Abstract
Systems, methods and techniques for exhaust gas recirculation are provided. The system includes a variable venturi device that connects an inlet air supply line and recirculating exhaust gas supply line to an intake manifold supply. A controller in communication with at least one pumping pressure sensor and a flow control element position sensor associated with the variable venturi mixing device is operable to determine a flow rate of the recirculating exhaust gas. The flow rate determination may be used to control NOx emissions during operation of the internal combustion engine.
Claims20
A method for determining a recirculated exhaust gas flow rate, comprising:
- determining a pumping pressure for the recirculated exhaust gas created by a variable venturi mixing device that fluidly mixes the recirculated exhaust gas with a fresh air supply;
- determining a position of a flow control element within the variable venturi mixing device;
- and
- determining the flow rate of the recirculated exhaust gas as a function of the pumping pressure and the position of the flow control element.
An exhaust gas recirculation system, comprising:
- an inlet air supply line;
- an internal combustion engine;
- a recirculating exhaust gas supply line connected to an exhaust manifold of the internal combustion engine;
- an intake manifold supply line connected to an intake manifold of the internal combustion engine;
- a variable venturi mixing device connecting the inlet air supply line and the recirculating exhaust gas supply line to the intake manifold supply line, wherein air entering through the inlet air supply line and exhaust gas entering though the recirculating exhaust gas supply line mix in the variable venturi mixing device to create a mixture of air and exhaust gas to the intake manifold supply line, the variable venturi mixing device including a flow control element positioned therein that is movable to any one of a plurality of positions;
- and
- a controller operable to determine a flow rate of the recirculating exhaust gas flowing through the recirculating exhaust gas supply line as a function of a current position of the flow control element and a current pumping pressure for the recirculating exhaust gas created by the variable venturi mixing device.
A control system for controlling an exhaust gas recirculation system, said control system comprising:
- a controller operable to receive a signal indicative of a current position of a flow control element of a variable venturi device, wherein the variable venturi device connects an inlet air supply line and a recirculating exhaust gas supply line to an intake manifold supply line;
- at least one sensor operable to generate a signal indicative of a current pumping pressure of the variable venturi device that draws recirculating exhaust gas from the recirculating exhaust gas supply line into the intake manifold supply line;
- and
- wherein the controller is in communication with the at least one sensor and operable to receive the sensor signal indicative of the sensed pumping pressure, the controller further being operable to generate a control signal based at least in part on a current flow rate of the recirculating exhaust gas determined according to the current position of the flow control element and the current pumping pressure.
Dependencies are inferred from the claim text.