Abstract: An exhaust gas control apparatus includes a control device controlling 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. When an ammonia adsorption amount in a predetermined part on a 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 thereof. The urea addition valve is controlled based on an adsorption amount distribution obtained from a model on which the catalyst is divided into 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 smaller than the threshold.

Abstract: Utilizing the finding that the state of adsorption of NH3 on a selective reduction type NOx catalyst includes a weakly adsorbed state in which the adsorbed NH3 is useful for a reduction reaction of NOx and a strongly adsorbed state in which the adsorbed NH3 is not useful for the reduction reaction of NOx unless the state of adsorption is changed into the weakly adsorbed state, the apparatus of the invention includes an actual weakly-adsorbed amount-calculation NH3 that is adsorbed on the selective reduction type NOx catalyst in the weakly adsorbed state, and a dispensation control portion that performs a dispensation control of the reductant dispensed by a reductant-dispensation portion, according to the actual weakly adsorbed amount calculated by the actual weakly adsorbed amount calculation portion.

Abstract: Utilizing the finding that the state of adsorption of NH3 on a selective reduction type NOx catalyst includes a weakly adsorbed state in which the adsorbed NH3 is useful for a reduction reaction of NOx and a strongly adsorbed state in which the adsorbed NH3 is not useful for the reduction reaction of NOx unless the state of adsorption is changed into the weakly adsorbed state, the apparatus of the invention includes an actual weakly-adsorbed amount-calculation NH3 that is adsorbed on the selective reduction type NOx catalyst in the weakly adsorbed state, and a dispensation control portion that performs a dispensation control of the reductant dispensed by a reductant-dispensation portion, according to the actual weakly adsorbed amount calculated by the actual weakly adsorbed amount calculation portion.

Abstract: A technique that, in an exhaust gas purification apparatus of an internal combustion engine, can avoid a decrease in a NOx purification rate by adding a reducing agent as continuously as possible, while avoiding NH3 from passing through a selective reduction type NOx catalyst to a downstream side thereof. The selective reduction type NOx catalyst has an active spot which purifies NOx by the use of NH3, and an adsorption site which adsorbs NH3, wherein a vicinity site, which is located in the vicinity of the active spot, and a distant site, which is located distant from the active spot, exist in the adsorption site. The addition of the reducing agent from the reducing agent addition part is controlled based on the desorption rate of NH3 in the vicinity site so as to continue to cause the NH3 adsorbed to the vicinity site to exist.

Abstract: An object of the present invention is to increase the flexibility in the layout of an exhaust gas purification system for an internal combustion engine including selective catalytic reduction catalyst provided in an exhaust passage of the internal combustion engine and an addition device for supplying reducing agent derived from ammonia to the selective catalytic reduction catalyst, without a deterioration of the performance in reducing nitrogen oxides. To achieve the object, the exhaust gas purification system for an internal combustion engine according to the present invention is configured to supply hydrocarbon at the same time when reducing agent derived from ammonia is supplied to the selective catalytic reduction catalyst, thereby producing reducing agent that is hard to be oxidized by a precious metal catalyst.

Abstract: An exhaust gas purification system is equipped with a burner in an exhaust passage upstream of an exhaust gas purification apparatus and having a burner combustion chamber in which flame is produced. When the temperature of the exhaust gas purification apparatus is raised, the burner produces flame that extends from the interior of the burner combustion chamber to the interior of the exhaust passage when the flow rate of the exhaust gas is not higher than a predetermined flow rate, and the burner causes the size of the flame to be smaller than when it is determined that the flow rate of the exhaust gas is not higher than the predetermined flow rate or to produce flame only in the interior of the burner combustion chamber when it is determined that the flow rate of exhaust gas is higher than the predetermined flow rate.

Abstract: A technique that, in an exhaust gas purification apparatus of an internal combustion engine, can avoid a decrease in a NOx purification rate by adding a reducing agent as continuously as possible, while avoiding NH3 from passing through a selective reduction type NOx catalyst to a downstream side thereof. The selective reduction type NOx catalyst has an active spot which purifies NOx by the use of NH3, and an adsorption site which adsorbs NH3, wherein a vicinity site, which is located in the vicinity of the active spot, and a distant site, which is located distant from the active spot, exist in the adsorption site. The addition of the reducing agent from the reducing agent addition part is controlled based on the desorption rate of NH3 in the vicinity site so as to continue to cause the NH3 adsorbed to the vicinity site to exist.

Abstract: In an exhaust gas purification apparatus for an internal combustion engine, the regeneration of a filter and the purification of NOx are made compatible with each other while suppressing an excessive supply of HC.

Abstract: An exhaust emission purifier able to suppress overheats of an exhaust emission purifying catalyst and execute fuel addition promptly when fuel addition to the exhaust emission purifying catalyst is requested is provided. In the exhaust emission purifier of an internal combustion engine including exhaust emission purifying catalyst of purifying exhaust emission of an internal combustion engine and a fuel addition valve of adding fuel from upstream of the exhaust emission purifying catalyst, cycles are repeated in order that the exhaust emission purifying catalyst is to be regulated at a target temperature, the cycle being a combination of an addition period during which fuel is added from the fuel addition valve and a halt period during which fuel addition is halted, and the fuel addition valve is manipulated such that the halt period is disposed so as to sandwich the addition period in the cycle.

Abstract: In an exhaust gas purification apparatus for an internal combustion engine, reducing agent is diffused and the exhaust resistance is made small. The apparatus includes a reducing agent addition valve that injects reducing agent, a reducing agent addition valve mount portion that has a space in which the reducing agent addition valve injects the reducing agent outside a stream of exhaust gas flowing in an exhaust passage of an internal combustion engine and on which the reducing agent addition valve is mounted, and an impingement portion that is provided in the reducing agent addition valve mount portion and on which the reducing agent injected through the reducing agent addition valve impinges, wherein the direction of injection of the reducing agent from the reducing agent addition valve is oriented toward the impingement portion, and toward downstream of the reducing agent addition valve with respect to the exhaust gas flow.

Abstract: In an exhaust gas control apparatus for an internal combustion engine (1) of the invention, including an exhaust gas control catalyst (8) which purifies exhaust gas released from the internal combustion engine (1), and a fuel supply valve (10) which supplies fuel to a portion upstream of the exhaust gas control catalyst (8), the fuel supply valve (10) is operated such that a cycle formed by combining a fuel supply period in which fuel is supplied from the fuel supply valve (10) and a fuel supply stopped period in which fuel is not supplied is repeatedly performed in order to control the temperature of the exhaust gas control catalyst (8) to the target temperature. The arrangement of the fuel supply period and the fuel supply stopped period is controlled such that the temperature of the exhaust gas control catalyst (8) at each of a starting point (P1) and an ending poring (P3) of each cycle is equal to the target temperature.

Abstract: An exhaust emission purifier is provided and able to suppress overheating of an exhaust emission purifying catalyst and execute fuel addition promptly when fuel addition to the exhaust emission purifying catalyst is requested. In the exhaust emission purifier of an internal combustion engine, exhaust purifying cycles are repeated in order that the exhaust emission purifying catalyst is to be regulated at a target temperature, the cycle being a combination of an addition period during which fuel is added from the fuel addition valve and a halt period during which fuel addition is halted, and the fuel addition valve is manipulated such that the halt period is disposed so as to sandwich the addition period in the cycle.

Abstract: To homogeneously diffuse, in the exhaust gas, an additive that is fed into a device for purifying exhaust gas of an internal combustion engine.

Abstract: In an exhaust gas purification apparatus for an internal combustion engine, reducing agent is diffused and the exhaust resistance is made small. The apparatus includes a reducing agent addition valve that injects reducing agent, a reducing agent addition valve mount portion that has a space in which the reducing agent addition valve injects the reducing agent outside a stream of exhaust gas flowing in an exhaust passage of an internal combustion engine and on which the reducing agent addition valve is mounted, and an impingement portion that is provided in the reducing agent addition valve mount portion and on which the reducing agent injected through the reducing agent addition valve impinges, wherein the direction of injection of the reducing agent from the reducing agent addition valve is oriented toward the impingement portion, and toward downstream of the reducing agent addition valve with respect to the exhaust gas flow.

Abstract: An evaluation device (22) comprises an evaluation target model (31) which operates according to a control algorithm to be implemented in the control system, and which outputs a manipulated variable of a predetermined controlled equipment (8) included in the physical device (1) in correspondence with a predetermined input condition, a state quantity presumption model (32) which presumes a state quantity of the physical device subjected to an influence of an operation of the controlled equipment in correspondence with a predetermined state quantity presumption condition, and which outputs the presumed state quantity, and a model control device (33) which provides the input condition to the evaluation target model so that the manipulated variable is output therefrom.

Abstract: An object of the present invention is to provide a technology that enables efficient utilization of the purification capability of an exhaust gas purification apparatus. To achieve the object, according to the present invention, in an exhaust system of an internal combustion engine provided with a reducing agent supply apparatus that supplies a reducing agent to the exhaust gas before it flows into an exhaust gas purification apparatus, an extension chamber is provided downstream of the position at which the reducing agent supply apparatus supplies the reducing agent to the exhaust gas and upstream of the exhaust gas purification apparatus. The extension chamber is provided with a back step flow creating portion that creates a back step flow of the exhaust gas in the extension chamber and a swirling flow creating portion that creates a swirling flow.

Abstract: In an exhaust gas purification apparatus for an internal combustion engine, the regeneration of a filter and the purification of NOx are made compatible with each other while suppressing an excessive supply of HC.

Abstract: An exhaust emission purifier able to suppress overheats of an exhaust emission purifying catalyst and execute fuel addition promptly when fuel addition to the exhaust emission purifying catalyst is requested is provided. In the exhaust emission purifier of an internal combustion engine including exhaust emission purifying catalyst of purifying exhaust emission of an internal combustion engine and a fuel addition valve of adding fuel from upstream of the exhaust emission purifying catalyst, cycles are repeated in order that the exhaust emission purifying catalyst is to be regulated at a target temperature, the cycle being a combination of an addition period during which fuel is added from the fuel addition valve and a halt period during which fuel addition is halted, and the fuel addition valve is manipulated such that the halt period is disposed so as to sandwich the addition period in the cycle.

Abstract: An evaluation device (22) comprises an evaluation target model (31) which operates according to a control algorithm to be implemented in the control system, and which outputs a manipulated variable of a predetermined controlled equipment (8) included in the physical device (1) in correspondence with a predetermined input condition, a state quantity presumption model (32) which presumes a state quantity of the physical device subjected to an influence of an operation of the controlled equipment in correspondence with a predetermined state quantity presumption condition, and which outputs the presumed state quantity, and a model control device (33) which provides the input condition to the evaluation target model so that the manipulated variable is output therefrom.

Abstract: In an exhaust gas control apparatus for an internal combustion engine (1) of the invention, including an exhaust gas control catalyst (8) which purifies exhaust gas released from the internal combustion engine (1), and a fuel supply valve (10) which supplies fuel to a portion upstream of the exhaust gas control catalyst (8), the fuel supply valve (10) is operated such that a cycle formed by combining a fuel supply period in which fuel is supplied from the fuel supply valve (10) and a fuel supply stopped period in which fuel is not supplied is repeatedly performed in order to control the temperature of the exhaust gas control catalyst (8) to the target temperature. The arrangement of the fuel supply period and the fuel supply stopped period is controlled such that the temperature of the exhaust gas control catalyst (8) at each of a starting point (P1) and an ending poring (P3) of each cycle is equal to the target temperature.