Search International and National Patent Collections

1. (WO2013124532) METHOD FOR OPERATING INTERNAL COMBUSTION ENGINE

Pub. No.:    WO/2013/124532    International Application No.:    PCT/FI2013/050148
Publication Date: Fri Aug 30 01:59:59 CEST 2013 International Filing Date: Tue Feb 12 00:59:59 CET 2013
IPC: F02D 41/00
F02B 37/16
F02M 25/07
Applicants: WÄRTSILÄ FINLAND OY
Inventors: DELNERI, Diego
RIZZETTO, Gino
AXELSSON, Martin
SCROCCO, Pietro
Title: METHOD FOR OPERATING INTERNAL COMBUSTION ENGINE
Abstract:
The method for operating an internal combustion engine (1) comprises at least two different operating modes. In at least one operating mode the intake valves (12) are closed during the intake stroke before bottom dead center for lowering the pressure in the cylinders (3), and internal exhaust gas recirculation (EGR) is used by reopening the exhaust valves (13) after the closing of the intake valves and before bottom dead center for allowing exhaust gas recirculation from the exhaust duct (4) into the cylinders (3). Water is injected into exhaust ports (4a) for cooling the recirculated exhaust gas. Different valve overlap durations are used in different operating modes for regulating the amount of the exhaust gas that is trapped within the cylinders (3) and in at least one operating mode the amount of the recirculated exhaust gas is regulated by means of a by-pass valve (7) that is arranged between an intake duct (2) and an exhaust duct (4) of the engine (1).