摘要:
A particulate accumulation amount estimating system is configured to accurately estimate an amount of particulate matter accumulated in a particulate filter based on the pressure difference across the particulate filter even when ash is accumulated in the particulate filter. The particulate accumulation amount estimating system is configured to estimate a particulate accumulation amount of particulate matter accumulated in the particulate filter based on a pressure difference that was detected across the particulate filter and an effective area change of the particulate filter that was detected due to the accumulation of ash in the particulate filter. The estimate of the particulate accumulation amount based on the pressure difference across the filter will be lower as the estimate value of the ash accumulation amount becomes larger.
摘要:
In an engine (10) comprising a fuel injector (12) which performs a post injection after performing a main injection into a cylinder and an exhaust valve (15) which opens and closes to discharge an exhaust gas, a controller (70) controls the fuel injector (12) to start the post injection during a period where a gas velocity in the cylinder along a cylinder axis increases after the exhaust valve (15) opens. A duration (t) of the post injection is controlled according to a crank angle at which the post injection is to be performed such that a breakup distance (L) at the end of which the injected fuel atomizes does not become larger than a distance (S) from an injection hole (12a) to a cylinder liner (10c), thereby ensuring that the injected fuel is supplied to an exhaust passage (23) without adhering to the cylinder liner (10c).
摘要:
A particulate accumulation amount estimating system is configured to accurately estimate an amount of particulate matter accumulated in a particulate filter based on the pressure difference across the particulate filter even when ash is accumulated in the particulate filter. The particulate accumulation amount estimating system is configured to estimate a particulate accumulation amount of particulate matter accumulated in the particulate filter based on a pressure difference that was detected across the particulate filter and an effective area change of the particulate filter that was detected due to the accumulation of ash in the particulate filter. The estimate of the particulate accumulation amount based on the pressure difference across the filter will be lower as the estimate value of the ash accumulation amount becomes larger.
摘要:
In an engine (10) comprising a fuel injector (12) which performs a post injection after performing a main injection into a cylinder and an exhaust valve (15) which opens and closes to discharge an exhaust gas, a controller (70) controls the fuel injector (12) to start the post injection during a period where a gas velocity in the cylinder along a cylinder axis increases after the exhaust valve (15) opens. A duration (t) of the post injection is controlled according to a crank angle at which the post injection is to be performed such that a breakup distance (L) at the end of which the injected fuel atomizes does not become larger than a distance (S) from an injection hole (12a) to a cylinder liner (10c), thereby ensuring that the injected fuel is supplied to an exhaust passage (23) without adhering to the cylinder liner (10c).
摘要:
To prevent an increase in torque when the fixed state of a throttle valve is released. When diagnostics reads fixed diagnostics flag 1 indicating that the throttle valve is in a fixed state, control value ATVO that can maintain throttle aperture RTVO is set (S11, S12) based on detected value RTVO for the throttle aperture in the current fixed state, fuel injection volume TiO that is calculated according to new air volume Q is secured at fuel injection volume TiL or greater in order to achieve the engine torque for when fail-safe control is executed, and when air-fuel ratioλis less than the lower limit valueλL, causing an increase in the amount of smoke, control is executed to suppress the occurrence of said smoke.
摘要:
A NOx purging system using a direct reduction type NOx catalyst, wherein sulfur is purged while avoiding the occurrence of secondary sulfur poisoning, taking advantage of capability of recovery from deterioration caused by sulfur poisoning at exhaust gas temperature exhibited at normal operating zone, so that the influence of sulfur poisoning can be eliminated and NOx is efficiently purged; and a method of reactivating deteriorated catalyst therein. In particular, a NOx purging system (10) comprising exhaust gas passage (2) and, arranged therein, direct reduction type NOx catalyst (3), which NOx purging system (10) is fitted with first sulfur purge control means (222) for performing such first sulfur purge operation that when exhaust gas temperature (Tg) becomes higher than given set temperature (T1) during normal operation, not only is the oxygen concentration of exhaust gas decreased but also the exhaust temperature (Tg) is raised to not below sulfur purge temperature (Tr).
摘要:
To prevent an increase in torque when the fixed state of a throttle valve is released. When diagnostics reads fixed diagnostics flag 1 indicating that the throttle valve is in a fixed state, control value ATVO that can maintain throttle aperture RTVO is set (S 11, S 12) based on detected value RTVO for the throttle aperture in the current fixed state, fuel injection volume TiO that is calculated according to new air volume Q is secured at fuel injection volume TiL or greater in order to achieve the engine torque for when fail-safe control is executed, and when air-fuel ratio), is less than the lower limit valueXL, causing an increase in the amount of smoke, control is executed to suppress the occurrence of said smoke.
摘要:
A compression-ignition internal combustion engine for conducting pilot injection and main injection beyond the top dead center, wherein pilot injection quantity and timing are optimized. A compression-ignition internal combustion engine, comprising a fuel injection valve for injecting fuel into a combustion chamber in a cylinder, the quantity and timing of the fuel injected through the fuel injection valve being controlled based on engine operating conditions; wherein pilot injection is carried out prior to the top dead center of compression, main injection is then carried out beyond the top dead center of compression, and fuel injection quantity and fuel injection timing of the pilot injection are set such that the maximum rate of heat release induced by the pilot injection is 60 kJ/s or less.
摘要:
To provide an exhaust gas purifying system and a control method therefor, capable of burning and removing PM collected at the downstream side of a DPF by utilizing HC and CO generated when performing the operation for recovering the NOx direct reduction type catalyst from a catalyst deterioration due to poisoning with sulfur. The exhaust gas purifying system (10) having a NOx direct reduction type catalyst (3) for purging NOx in an exhaust gas and a DPF (4) with a catalyst for purging PM in the exhaust gas are sequentially arranged in an exhaust gas passage (2) in that order in the direction of from an upstream side to a downstream side, which further comprises an air supply system (5) for supplying air (Aa) between the NOx direct reduction type catalyst (3) and the DPF (4) with a catalyst during a operation for recovering the NOx direct reduction type catalyst (3) from a catalyst deterioration due to poisoning with sulfur by bringing the oxygen concentration in the exhaust gas to be substantially zero and raising the exhaust gas temperature.
摘要:
Adequate controllability is ensured when feedback control is provided to both the EGR valve and the intake throttle valve, and switching shock is prevented when control is switched from one to the other. The present apparatus comprises an EGR valve, an intake throttle valve, feedback control means for providing feedback control to the EGR valve and intake throttle valve such that the actual EGR volume approximates the target EGR volume corresponding to the running condition of the engine, and limiting means for limiting the operable opening ranges of the EGR valve and intake throttle valve in accordance with the target EGR volume. During EGR control of one valve, feedback control is provided to the other valve and the target opening is constantly calculated. The actual operations are merely limited, so these operations can start from the optimal opening and the switching shock can be prevented when a switch is made to the control of the other valve.