Flex fuel internal combustion engine system
First Claim
Patent Images
1. A method of operating a flex fuel combustion system, comprising:
- determining the ethanol concentration in the fuel for the combustion system;
adjusting fuel and air intake into the combustion system in order to maintain stoichiometry if the ethanol concentration is determined to be less than a threshold value;
adjusting fuel and air intake into the combustion system to provide lean combustion at higher efficiency if the ethanol concentration is determined to be above the threshold value.
0 Assignments
0 Petitions
Accused Products
Abstract
A flex fuel internal combustion engine system includes means for sensing ethanol concentration of the fuel. If the ethanol concentration is determined to be above a given threshold, engine operation is adjusted for lean combustion of the fuel. An aftertreatment system is provided to remove harmful emissions from the exhaust.
26 Citations
5 Claims
-
1. A method of operating a flex fuel combustion system, comprising:
-
determining the ethanol concentration in the fuel for the combustion system; adjusting fuel and air intake into the combustion system in order to maintain stoichiometry if the ethanol concentration is determined to be less than a threshold value; adjusting fuel and air intake into the combustion system to provide lean combustion at higher efficiency if the ethanol concentration is determined to be above the threshold value. - View Dependent Claims (2)
-
-
3. A flex-fuel combustion and aftertreatment system, comprising:
-
an engine; a fuel tank configured to hold a fuel comprising gasoline, ethanol, or a mixture thereof, for combustion in the engine; a fuel injector fluidly connected to the fuel tank, configured to provide the fuel for combustion in the engine; means for determining the ethanol concentration of the fuel; means for controlling the fuel injector and air intake valve, programmed to maintain stoichiometric air-fuel ratio if the ethanol concentration is determined to be less than a threshold value, but to provide substantial excess air for lean combustion at higher efficiency if the ethanol concentration is not determined to be less than the threshold value; a three-way catalyst for cleaning exhaust from the combustion; and a lean NOx aftertreatment device to remove harmful emissions from combustion. - View Dependent Claims (4)
-
-
5. A flex-fuel combustion and aftertreatment system, comprising:
-
an engine; a fuel tank configured to hold a fuel for combustion in the engine; fuel injectors fluidly connected to the fuel tank, configured to provide the fuel for combustion in the engine; means for determining the sulfur concentration of the fuel; means for controlling the fuel injectors and an air intake valve, programmed to maintain stoichiometric air-fuel ratio if the sulfur concentration is determined to be greater than a threshold value, but to provide substantial excess air for lean combustion at higher efficiency if the sulfur concentration is not determined to be greater than the threshold value; a three-way catalyst for cleaning exhaust from the combustion; and a lean NOx aftertreatment device to remove harmful emissions from combustion.
-
Specification