摘要:
An exhaust gas control apparatus includes a control device that controls a urea addition valve for adding urea from an upstream side of a NOx reduction catalyst. The control device obtains an ammonia adsorption amount distribution through the NOx reduction catalyst, and when an ammonia adsorption amount in a predetermined part on an exhaust gas flow direction downstream side equals or exceeds a predetermined threshold, the control device controls the urea addition valve to stop the urea supply or reduce the amount of urea supply. The urea addition valve is controlled basis on an adsorption amount distribution obtained from a model on which the catalyst is divided into a plurality of cells such that an ammonia adsorption amount in a first cell positioned furthest upstream equals or exceeds a predetermined threshold close to a saturation adsorption amount and an ammonia adsorption amount in a second cell positioned downstream of the first cell reaches a predetermined target value that is smaller than the threshold.
摘要:
An exhaust gas control apparatus includes a control device that controls a urea addition valve for adding urea from an upstream side of a NOx reduction catalyst. The control device obtains an ammonia adsorption amount distribution through the NOx reduction catalyst, and when an ammonia adsorption amount in a predetermined part on an exhaust gas flow direction downstream side equals or exceeds a predetermined threshold, the control device controls the urea addition valve to stop the urea supply or reduce the amount of urea supply. The urea addition valve is controlled basis on an adsorption amount distribution obtained from a model on which the catalyst is divided into a plurality of cells such that an ammonia adsorption amount in a first cell positioned furthest upstream equals or exceeds a predetermined threshold close to a saturation adsorption amount and an ammonia adsorption amount in a second cell positioned downstream of the first cell reaches a predetermined target value that is smaller than the threshold.
摘要:
An exhaust gas control apparatus includes a control device that controls a urea addition valve for adding urea from an upstream side of a NOx reduction catalyst. The control device obtains an ammonia adsorption amount distribution through the NOx reduction catalyst, and when an ammonia adsorption amount in a predetermined part on an exhaust gas flow direction downstream side equals or exceeds a predetermined threshold, the control device controls the urea addition valve to stop the urea supply or reduce the amount of urea supply. The urea addition valve is controlled basis on an adsorption amount distribution obtained from a model on which the catalyst is divided into a plurality of cells such that an ammonia adsorption amount in a first cell positioned furthest upstream equals or exceeds a predetermined threshold close to a saturation adsorption amount and an ammonia adsorption amount in a second cell positioned downstream of the first cell reaches a predetermined target value that is smaller than the threshold.
摘要:
An exhaust gas control apparatus includes a control device (8) that controls a urea addition valve for adding urea from an upstream side of a NOx reduction catalyst (7). The control device (6) obtains an ammonia adsorption amount distribution through the NOx reduction catalyst (7), and when an ammonia adsorption amount in a predetermined part on an exhaust gas flow direction downstream side equals or exceeds a predetermined threshold, the control device (8) controls the urea addition valve (6) to stop the urea supply or reduce the amount of urea supply. The urea addition valve (6) is controlled basis on an adsorption amount distribution obtained from a model on which the catalyst is divided into a plurality of cells such that an ammonia adsorption amount in a first cell (71) positioned furthest upstream equals or exceeds a predetermined threshold close to a saturation adsorption amount and an ammonia adsorption amount in a second cell (72) positioned downstream of the first cell (71) reaches a predetermined target value that is smaller than the threshold.
摘要:
An exhaust gas purification apparatus for an internal combustion engine comprises: a selective catalytic reduction (SCR) catalyst selectively reducing NOx in an exhaust gas of the internal combustion engine using ammonia as a reducing agent; a supply device adding an additive agent, such as ammonia, to the exhaust gas at an upstream side of the SCR catalyst; and a controller, when a temperature of SCR catalyst is higher than a predetermined temperature, increases a NOx concentration of the exhaust gas flowing into the SCR catalyst and increases an amount of addition of the additive agent in such a manner that a ratio of an amount of ammonia with respect to an amount of NOx contained in the exhaust gas flowing into the SCR catalyst, becomes large, as compared to when the temperature is equal to or less than the predetermined temperature.