Abstract: An exhaust gas control method of an engine may include calculating a target mass flux of EGR gas by using air mass entering into a cylinder and target air mass supplied into the engine, calculating a target effective flow area (EFAd) of the EGR valve by using the target mass flux of the EGR gas and front/rear condition of the EGR valve, and calculating a valve opening rate of the EGR valve by using a predetermined curve fitting formula and the target effective flow area (EFAd).

Abstract: An EGR system control method of an engine may include calculating a target mass flux ({dot over (m)}egrd) of EGR gas flowing an EGR line, calculating an effective flowing area (EFA) of an EGR valve disposed on the EGR line, calculating an EGR flow sensitivity by dividing the target mass flux with the effective flowing area, and controlling a real opening rate of the EGR valve by applying the EGR flow sensitivity to a target opening rate of the EGR valve. Accordingly, a gain value is varied on a real time according to an effective flowing area of the EGR valve and a target mass flux of EGR gas such that real opening rate of an EGR valve is accurately and precisely controlled.

Abstract: An EGR system control method of an engine may include calculating a target mass flux ({dot over (m)}egrd) of EGR gas flowing an EGR line, calculating an effective flowing area (EFA) of an EGR valve disposed on the EGR line, calculating an EGR flow sensitivity by dividing the target mass flux with the effective flowing area, and controlling a real opening rate of the EGR valve by applying the EGR flow sensitivity to a target opening rate of the EGR valve. Accordingly, a gain value is varied on a real time according to an effective flowing area of the EGR valve and a target mass flux of EGR gas such that real opening rate of an EGR valve is accurately and precisely controlled.

Abstract: An exhaust gas control method of an engine may include calculating a target mass flux of EGR gas by using air mass entering into a cylinder and target air mass supplied into the engine, calculating a target effective flow area (EFAd) of the EGR valve by using a target mass flux of the EGR gas and front/rear condition of the EGR valve, and calculating a valve opening rate of the EGR valve by using a predetermined curve fitting formula and the target effective flow area (EFAd). Accordingly, a target mass flux of EGR gas flowing an EGR line is calculated to be applied an opening rate of the EGR valve thereby such that a flux of the EGR gas precisely and quickly is control.