Method of estimating the fuel/air ratio of an internal combustion engine

Patent · Tue Dec 06 04:00:00 EST 1988

OSTI ID:6423066

Javaherian, H

This patent describes a method of estimating the ratio of the air and fuel mixture supplied to a cylinder of an internal combustion engine through an intake valve that is closed upon completion of the intake phase of the cylinder to trap an air-fuel charge in the cylinder at a predetermined crank angle during rotation of an output crankshaft of the engine, the intake phase being followed by a compression phase and a combustion phase as the engine crank angle increases, the method comprising the steps of: (a) determining the trapped charge mass m in the cylinder; (b) setting an initial estimated fuel/air ratio value; (c) for the estimated fuel/air ratio, determining the gas pressure in the cylinder and the engine crank angle corresponding thereto at which the mass fraction burned ..mu../sub b/ during combustion represents substantially complete combustion; (d) determining the mass burned m'/sub f/ based on the pressure and crank angle at which the mass fraction burned ..mu../sub b/ during combustion represented substantially complete combustion; (e) computing the total fuel mass burned m/sub f/ during combustion.

• Assignee: General Motors Corp., Detroit, MI
• Patent Number(s): US 4788854
• OSTI ID: 6423066
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
99 GENERAL AND MISCELLANEOUS
990220 -- Computers
Computerized Models
& Computer Programs-- (1987-1989)
COMPUTER CALCULATIONS
CONTROL EQUIPMENT
ENGINES
EQUIPMENT
FLOW REGULATORS
FUEL SYSTEMS
FUEL-AIR RATIO
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
METERING
OPERATION
VALVES