Soot catcher purgative diesel engine intake throttling method and

Abstract

A method for intake throttling for a diesel engine provided with an exhaust gas soot catcher, which also has an intake throttle valve for restricting intake air, thus heating the exhaust gases for purging the soot catcher. When the soot catcher is clogged with soot, throttling operation of the intake throttling valve is commenced after a first time period has elapsed after the point which represents the current operational condition of the diesel engine in a phase space whose dimensions are certain operating parameters of the diesel engine has transited from a first region representing non intake throttling combinations of these certain operating parameters to a second region, the complement of the first region, representing intake throttling combinations of these operating parameters; and/or such throttling operation of the intake throttling valve is ceased after a second time period has elapsed after this point has transited to this first region from this second region. Thus at proper times the soot catcher is heated up by heating up of the exhaust gases, with a proper time delay incorporated in this heating up of the exhaust gases, and is purged by combusting the accumulation of soot particles in it; and/or the heating up of the soot catcher to purge it is terminated by termination of the heating up of the exhaust gases, with a proper time delay incorporated in this termination of heating up of the exhaust gases. Apparatus is also described for practicing this method.