초록 ▼

A method to dynamically determine a parametric value for combustion chamber deposits (CCD), e.g. in a controlled auto-ignition engine, including in-situ evaluation of thickness of CCD, based on a sensor which monitors combustion in a homogeneous charge compression ignition engine. It includes a temp

A method to dynamically determine a parametric value for combustion chamber deposits (CCD), e.g. in a controlled auto-ignition engine, including in-situ evaluation of thickness of CCD, based on a sensor which monitors combustion in a homogeneous charge compression ignition engine. It includes a temperature sensor operative to monitor the combustion chamber, and a CCD parameter that is based upon a peak combustion temperature measured at a crank angle. A CCD parameter can also be determined utilizing an in-cylinder pressure monitor, wherein a combustion chamber deposit parameter is based upon crank angle location of a peak in-cylinder pressure parameter.

대표청구항 ▼

The invention claimed is: 1. Method for determining a parameter for combustion chamber deposits of an internal combustion engine adapted to be operative in a controlled auto-ignition combustion mode, said engine comprising a spark-ignition, direct-injection, four-stroke, internal combustion engine

The invention claimed is: 1. Method for determining a parameter for combustion chamber deposits of an internal combustion engine adapted to be operative in a controlled auto-ignition combustion mode, said engine comprising a spark-ignition, direct-injection, four-stroke, internal combustion engine including a variable volume combustion chamber defined by a piston reciprocating within a cylinder between top-dead-center and bottom-dead-center points and a cylinder head, said piston operably connected to a rotating crankshaft, the method comprising: monitoring a combustion parameter; determining a combustion chamber deposit parameter based upon the combustion parameter; and wherein monitoring the combustion parameter comprises monitoring a combustion chamber surface temperature and a related engine crank angle. 2. The method of claim 1, wherein determining a combustion chamber deposit parameter based upon the combustion parameter comprises: determining magnitude of combustion chamber deposits based upon an engine crank angle at which a peak combustion chamber surface temperature occurs during an engine cycle. 3. Method for determining a parameter for combustion chamber deposits of an internal combustion engine adapted to be operative in a controlled auto-ignition combustion mode, said engine comprising a spark-ignition, direct-injection, four-stroke, internal combustion engine including a variable volume combustion chamber defined by a piston reciprocating within a cylinder between top-dead-center and bottom-dead-center points and a cylinder head, said piston operably connected to a rotating crankshaft, the method comprising: monitoring a combustion parameter comprising monitoring a related engine crank angle, determining an in-cylinder combustion pressure parameter during each engine cycle, and determining the combustion pressure parameter based upon a peak in-cylinder pressure and the crank angle location of the peak in-cylinder pressure; and determining a combustion chamber deposit parameter based upon the combustion parameter. 4. The method of claim 3, wherein determining the in-cylinder combustion pressure parameter comprises monitoring output of an in-cylinder pressure sensing device. 5. The method of claim 3, wherein determining the in-cylinder combustion pressure parameter comprises monitoring an in-cylinder spark ionization signal. 6. A method for operating a multi-cylinder direct-injection, four-stroke internal combustion engine capable of operating with a controlled auto-ignition process, comprising: determining a parametric measure of combustion chamber deposits; and, controlling engine operation based upon the combustion chamber deposit parameter, wherein determining a parametric measure of combustion chamber deposits comprises: monitoring a combustion parameter and determining a parametric measure of combustion chamber deposits based upon said combustion parameter comprising determining magnitude of combustion chamber deposits based upon an engine crank angle at which a peak combustion chamber surface temperature occurs during an engine cycle. 7. The method of claim 6, wherein monitoring the combustion parameter further comprises: monitoring a related engine crank angle; determining an in-cylinder combustion pressure parameter during each engine cycle; and determining the combustion pressure parameter based upon a peak in-cylinder pressure and the crank angle location of the peak in-cylinder pressure. 8. The method of claim 7, wherein determining the in-cylinder combustion pressure parameter comprises monitoring output of an in-cylinder pressure sensing device. 9. The method of claim 7, wherein determining the in-cylinder combustion pressure parameter comprises monitoring an in-cylinder spark ionization signal.