Spark-ignition internal combustion engine having urea introduction device and method for operating an internal combustion engine of this type

Patent metadata

Field	Value
Publication number	US-11111884-B2
Application number	US-201916963805-A
Country	US
Kind code	B2
Filing date	Jan 18, 2019
Priority date	Feb 5, 2018
Publication date	Sep 7, 2021
Grant date	Sep 7, 2021

Abstract

A spark-ignition internal combustion engine has an air intake tract for supplying fresh air to a combustion chamber of the spark-ignition internal combustion engine, an exhaust tract for discharging exhaust gases from the combustion chamber, and a urea introduction device having a urea injection nozzle for introducing an aqueous urea solution into the combustion chamber. The urea injection nozzle is disposed in the combustion chamber or upstream of the combustion chamber in relation to an air flow from the air intake tract into the combustion chamber.

First claim

What is claimed is:

1. A spark-ignition internal combustion engine, comprising:
a combustion chamber;
an air inlet tract, wherein air is suppliable to the combustion chamber via the air inlet tract;
an exhaust tract, wherein exhaust gases are dischargeable from the combustion chamber via the exhaust tract; and
a urea introduction device with a urea injection nozzle, wherein an aqueous urea solution is introducible into the combustion chamber via the urea injection nozzle, wherein the urea injection nozzle is disposed in the combustion chamber or upstream of the combustion chamber with respect to an air flow from the air inlet tract into the combustion chamber, and wherein the aqueous urea solution is a liquid which comprises urea and demineralized water.

2. A method for operating the spark-ignition internal combustion engine according to claim 1 , comprising the acts of:
operating the spark-ignition internal combustion engine as a four stroke engine with an intake stroke, a compression stroke, a working stroke, and an exhaust stroke;
at least during the intake stroke introducing an aqueous urea solution directly into the air inlet tract or into the combustion chamber by the urea injection nozzle; and
cooling an air flowing into the combustion chamber through the air inlet tract by evaporation of the aqueous urea solution.

3. The spark-ignition internal combustion engine according to claim 1 , wherein the aqueous urea solution comprises 32.5% of urea and 67.5% of demineralized water.

4. The spark-ignition internal combustion engine according to claim 1 , wherein the urea injection nozzle is disposed in the combustion chamber.

Assignees

• Bayerische Motoren Werke Ag

Inventors

• Pueschel Eckard

Classifications

• F02M25/03 Primary

  into the cylinder {or the pre-combustion chamber} · CPC title

• F02B47/00

  Methods of operating engines involving adding non-fuel substances or anti-knock agents to combustion air, fuel, or fuel-air mixtures of engines · CPC title

• F02M25/028

  into the charge intakes · CPC title

• Y02T10/12

  Improving ICE efficiencies · CPC title

• F02D41/0025

  Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures · CPC title