摘要:
A method is disclosed for controlling operation of an engine coupled to an exhaust treatment catalyst. Under predetermined conditions, the method operates an engine with a first group of cylinders combusting a lean air/fuel mixture and a second group of cylinders pumping air only (i.e., without fuel injection). In addition, the engine control method also provides the following features in combination with the above-described split air/lean mode: idle speed control, sensor diagnostics, air/fuel ratio control, adaptive learning, fuel vapor purging, catalyst temperature estimation, default operation, and exhaust gas and emission control device temperature control. In addition, the engine control method also changes to combusting in all cylinders under preselected operating conditions such as fuel vapor purging, manifold vacuum control, and purging of stored oxidants in an emission control device.
摘要:
A method is disclosed for controlling operation of an engine coupled to an exhaust treatment catalyst. Under predetermined conditions, the method operates an engine with a first group of cylinders combusting a lean air/fuel mixture and a second group of cylinders pumping air only (i.e., without fuel injection). In addition, the engine control method also provides the following features in combination with the above-described split air/lean mode: idle speed control, sensor diagnostics, air/fuel ratio control, adaptive learning, fuel vapor purging, catalyst temperature estimation, default operation, and exhaust gas and emission control device temperature control. In addition, the engine control method also changes to combusting in all cylinders under preselected operating conditions such as fuel vapor purging, manifold vacuum control, and purging of stored oxidants in an emission control device.
摘要:
A method is disclosed for controlling operation of an engine coupled to an exhaust treatment catalyst. Under predetermined conditions, the method operates an engine with a first group of cylinders combusting a lean air/fuel mixture and a second group of cylinders pumping air only (i.e., without fuel injection). In addition, the engine control method also provides the following features in combination with the above-described split air/lean mode: idle speed control, sensor diagnostics, air/fuel ratio control, adaptive learning, fuel vapor purging, catalyst temperature estimation, default operation, and exhaust gas and emission control device temperature control. In addition, the engine control method also changes to combusting in all cylinders under preselected operating conditions such as fuel vapor purging, manifold vacuum control, and purging of stored oxidants in an emission control device.
摘要:
A method is disclosed for controlling operation of an engine coupled to an exhaust treatment catalyst. Under predetermined conditions, the method operates an engine with a first group of cylinders combusting a lean air/fuel mixture and a second group of cylinders pumping air only (i.e., without fuel injection). In addition, the engine control method also provides the following features in combination with the above-described split air/lean mode: idle speed control, sensor diagnostics, air/fuel ratio control, adaptive learning, fuel vapor purging, catalyst temperature estimation, default operation, and exhaust gas and emission control device temperature control. In addition, the engine control method also changes to combusting in all cylinders under preselected operating conditions such as fuel vapor purging, manifold vacuum control, and purging of stored oxidants in an emission control device.
摘要:
A system for trapping liquid exhaust during a cold start of an internal combustion engine is provided. As one example, a system includes, an exhaust inlet, an exchange area fluidly coupled downstream of said exhaust inlet, a trap coupled to said exchange area having a liquid exhaust chamber for collection of liquid exhaust, and a catalytic converter fluidly coupled downstream to said exchange area. In another example, a method includes condensing, at least partly, exhaust from the engine in an exchange area in an exhaust system into liquid exhaust, collecting liquid exhaust into a trap disposed in the exchange area, and evaporating the liquid exhaust into the exchange area after an evaporation temperature is reached in the trap.
摘要:
A method is disclosed for controlling operation of an engine coupled to an exhaust treatment catalyst. Under predetermined conditions, the method operates an engine with a first group of cylinders combusting a lean air/fuel mixture and a second group of cylinders pumping air only (i.e., without fuel injection). In addition, the engine control method also provides the following features in combination with the above-described split air/lean mode: idle speed control, sensor diagnostics, air/fuel ratio control, adaptive learning, fuel vapor purging, catalyst temperature estimation, default operation, and exhaust gas and emission control device temperature control. In addition, the engine control method also changes to combusting in all cylinders under preselected operating conditions such as fuel vapor purging, manifold vacuum control, and purging of stored oxidants in an emission control device.
摘要:
A system for trapping liquid exhaust during a cold start of an internal combustion engine is provided. As one example, a system includes, an exhaust inlet, an exchange area fluidly coupled downstream of said exhaust inlet, a trap coupled to said exchange area having a liquid exhaust chamber for collection of liquid exhaust, and a catalytic converter fluidly coupled downstream to said exchange area. In another example, a method includes condensing, at least partly, exhaust from the engine in an exchange area in an exhaust system into liquid exhaust, collecting liquid exhaust into a trap disposed in the exchange area, and evaporating the liquid exhaust into the exchange area after an evaporation temperature is reached in the trap.
摘要:
A method is described for operating an engine coupled to an emission control device that stores and reacts oxidants such as NOx. The method transitions from lean to stoichiometric or rich operation under various conditions. For example, a periodic transition is performed with an amount of NOx stored in the device reaches a threshold, or when a tip-in from idle conditions has been identified.
摘要:
A method is disclosed for controlling operation of an engine coupled to an exhaust treatment catalyst. Under predetermined conditions, the method operates an engine with a first group of cylinders combusting a lean air/fuel mixture and a second group of cylinders pumping air only (i.e., without fuel injection). In addition, the engine control method also provides the following features in combination with the above-described split air/lean mode: idle speed control, sensor diagnostics, air/fuel ratio control, adaptive learning, fuel vapor purging, catalyst temperature estimation, default operation, and exhaust gas and emission control device temperature control. In addition, the engine control method also changes to combusting in all cylinders under preselected operating conditions such as fuel vapor purging, manifold vacuum control, and purging of stored oxidants in an emission control device.
摘要:
A method for improving a purge conversion efficiency of a Lean NOx Trap coupled downstream of a lean-burn internal combustion engine is presented. This method recognizes that during a purge of the LNT, its temperature increases due to the exothermic reactions in the LNT. Once the LNT temperature exceeds a certain threshold, further increases lead to a reduction in the NOx storage capacity, and therefore an increase in NOx emissions during the purge of the LNT. Therefore, it is proposed to cool the LNT temperature once the threshold is exceeded. This method improves emission control and fuel economy during purge.