Patent Document ID: 9921131
Application ID: 13870482
Patent Flag: 1

Claim One:
1. A method for controlling an aftertreatment device based on estimating an engine-out NO x content of exhaust gas produced by an internal combustion engine, without the need to determine cylinder pressure, the method comprising: determining an engine speed and sending a signal indicative of the determined engine speed; determining an engine load and sending a signal indicative of the determined engine load; determining an intake oxygen level and sending a signal indicative of the determined intake oxygen level; determining a fuel pressure and sending a signal indicative of the determined fuel pressure; determining a fuel quantity and sending a signal indicative of the determined fuel quantity; and sending each of the signals indicative of the determined engine speed, engine load, intake oxygen level, fuel pressure, and fuel quantity to a control unit which is programmed to receive and process each of the signals indicative of determined engine speed, engine load, intake oxygen level, fuel pressure, and fuel quantity using a NO x model which utilizes a linear relationship between the intake oxygen level and engine-out NOx for the signal indicative of predetermined engine speed, and which utilizes a linear relationship between the intake oxygen level and engine-out NOx for the signal indicative of engine load, and which utilizes a linear relationship between the intake oxygen level and engine-out NOx for the signal indicative of intake oxygen level, and which utilizes a linear relationship between the intake oxygen level and engine-out NOx for the signal indicative of fuel pressure, and which utilizes a linear relationship between the intake oxygen level and engine-out NOx for the signal indicative of fuel quantity to arrive at an estimate of the engine-out NO x content; and controlling an aspect of the aftertreatment device based on the estimated engine-out NOx content.