Engine systems and methods use a dual air injection approach to control exhaust reactions and to maintain temperatures below a maximum limit of exhaust system components during engine enrichment operation conditions. Dual air injectors are disposed in the exhaust system with one upstream from, and another downstream from, the catalytic converter. Providing air injection before and/or after the converter helps convert all HC, CO, and PM emissions while keeping the catalyst temperature below the catalyst protection temperature limit. Air injection quantity may be controlled and diagnosed by monitoring the temperatures before and after the catalytic converter. The catalytic converter may be a three-way catalytic converter for lower cost or a downstream two-way catalytic converter may be added if further emission reduction is necessary.

Engine systems and methods use a dual air injection approach to control exhaust reactions and to maintain temperatures below a maximum limit of exhaust system components during engine enrichment operation conditions. Dual air injectors are disposed in the exhaust system with one upstream from, and another downstream from, the catalytic converter. Providing air injection before and/or after the converter helps convert all HC, CO, and PM emissions while keeping the catalyst temperature below the catalyst protection temperature limit. Air injection quantity may be controlled and diagnosed by monitoring the temperatures before and after the catalytic converter. The catalytic converter may be a three-way catalytic converter for lower cost or a downstream two-way catalytic converter may be added if further emission reduction is necessary.

An exhaust treatment device for a diesel engine is provided, which includes a parked regeneration requirement notification component and a parked regeneration start operation component. A regeneration process of the diesel particulate filter (DPF) includes an automatic regeneration process and a parked regeneration process. The automatic regeneration process is automatically started when an estimation value of particulate material (PM) accumulated in the DPF reaches a predetermined automatic regeneration start determination value. The parked regeneration process is performed when first and a second conditions are satisfied. The first condition is that a parked regeneration requirement notification component performs a notification of a parked regeneration requirement when a number of cancellations of the automatic regeneration process reaches a predetermined value. The second condition is that the parked regeneration start operation component is subjected to a start operation during a parked state in which an engine equipped machine is neither traveling nor working.

In a method and device for controlling and/or monitoring the function of a secondary air supply in an emission control system of an internal combustion engine, the emission control system includes at least two catalytic converters situated in succession in an exhaust duct, it being possible for the second catalytic converter to be implemented as a combination of catalytic converter and particulate filter. For a secondary air diagnosis and for secondary air control, a two-point lambda probe is situated, with respect to a direction of flow of exhaust gas, downstream of the first catalytic converter. Measures are applied for compensating tolerance and aging effects of the two-point lambda probe. This results in particular in cost advantages in emission control systems for fulfilling stricter emission requirements. In particular, this makes it possible to operate the particulate filter in optimized fashion.

A method and control device for correcting an output signal of an exhaust gas sensor in an exhaust gas conduit of an internal combustion engine, a secondary air delivery system for delivering air into the exhaust gas conduit being associated with the exhaust gas conduit upstream from the exhaust gas sensor in the flow direction of the exhaust gas. During a measurement of the output signal of the exhaust gas sensor, air is delivered to the exhaust gas conduit via the secondary air delivery system during a correction phase by way of which a correction of the output signal of the exhaust gas sensor is derived. In this operating mode, a defined oxygen content exists in the gas mixture surrounding said sensor, so that the output signal can be compared with reference values.

An EHC line leakage diagnosis method can operate a heater of an oxygen detector when satisfying one or more conditions of an engine off time, a coolant temperature, and an outside air temperature by a diagnosis controller upon the key-on of the non-operation of an engine, and then, determine the normality or abnormality of a temperature drop using a change in a temperature value of a signal value and the temperature value detected by the oxygen detector after an air pump is driven, and then confirm the leakage of an exhaust line and a line on the rear end portion of an EHC valve of an air line using the number of times of the occurrence of the abnormality of the temperature drop, and can perform the failure diagnosis without generating the exhaust gas by not operating an engine.

A method for checking the operability of a secondary-air system of an internal combustion engine includes measuring a first pressure between a first secondary-air pump and a first master secondary-air valve as well as a second master secondary-air valve, measuring a second pressure between a second secondary-air pump and a first slave secondary-air valve and a second slave secondary-air valve, controlling the first master secondary-air valve and the first slave secondary-air valve together, and controlling the second master secondary-air valve and the second slave secondary-air valve together. A secondary-air system includes a first control and a second control, wherein a first master secondary-air valve and a first slave secondary-air valve are controllable together by the first control and wherein a second master secondary-air valve and a second slave secondary-air valve are controllable together by the second control.

An airflow control system control system for a gas turbine system according to an embodiment includes: an airflow generation system including a plurality of air moving systems for selective attachment to a rotatable shaft of a gas turbine system, the airflow generation system drawing in an excess flow of air through an air intake section; and a mixing area for receiving an exhaust gas stream of the gas turbine system; the airflow generation system: directing a first portion and a second portion of the excess flow of air generated by the airflow generation system into the mixing area to reduce a temperature of the exhaust gas stream; and directing a third portion of the excess flow of air generated by the airflow generation system into a discharge chamber of a compressor component of the gas turbine system.

An exemplary vehicle exhaust system includes, among other things, a housing defining a fluid chamber and at least one pressure sensor positioned within the fluid chamber. The housing has a fluid inlet configured to receive fluid from a fluid supply and a fluid outlet. A heater heats fluid supplied from the fluid supply such that heated fluid can be injected into a vehicle exhaust component via the fluid outlet. A controller is configured to receive pressure data from the at least one pressure sensor and to determine optimal timing for dosing of the vehicle exhaust component based on the pressure data.

A device for adjusting and controlling the actual supplied amount of urea entering an exhaust system comprises an electronic control unit (1), a compressed air supply device (2), a urea storage device (3), a compressed air control device (4), a metering pump or a metering valve (5), a spray nozzle (6), a main pipeline (7), a urea pipeline (8), and a urea control device (9). The urea control device (9) is in communication with the electronic control unit (1) and controls the actual supplied amount of urea injected into the exhaust system from the spray nozzle according to the starting time point and the finishing time point. A method for adjusting and controlling the actual supplied amount of urea entering an exhaust system is also disclosed. The present device and method effectively prevent the excessive urea from being injected into the exhaust system, and enable the original exhaust system to match with stricter emission standards through a low cost improvement.