Secondary air injection

About: Secondary air injection is a research topic. Over the lifetime, 11452 publications have been published within this topic receiving 112147 citations.

Turbocharged engine with pressurized gas recirculation

Abstract: A multi-cylinder internal combustion engine, such as for a vehicle, having some of the cylinders connected to a first exhaust manifold and the remaining cylinders connected to a second exhaust manifold. The exhaust gases in the first exhaust manifold are used for driving the turbine section of a first turbocharger, the compressor section of which forces the air or air-fuel mixture into the intake manifold for distribution to the cylinders. The exhaust gases discharged from the first turbocharger are then supplied through an intermediate conduit to the compressor section of a second turbocharger, the turbine section of which is driven by the exhaust gases from the second exhaust manifold. The compressor section of the second turbocharger communicates with the intake manifold so that the fraction of the exhaust gases which are pressurized by the second turbocharger are mixed with the air or air-fuel mixture therein. A part of the exhaust gases are thus recycled through the cylinders to achieve higher compression ratios while utilizing leaner fuel mixtures.

Method and device for simultaneous regulation of an intake air flow for an internal combustion engine and a secondary air flow in the exhaust system of the same internal combustion engine

Abstract: The invention concerns a method and a device for simultaneous regulation of an intake air flow (24) of an internal combustion engine (10) and a secondary air flow (21) in the exhaust system (12) of the internal combustion engine, wherein the secondary air flow is produced by a compressor (20) powered by a turbine (18). The turbine (18) is mounted in a bypass (16), wherein said bypass is disposed parallel to a throttle valve (14) in the intake tract (11) of the internal combustion engine. The amount (21) of secondary air supplied thereby depends on the position of the throttle valve. In order to provide compensation therefor, a regulating valve (32) is provided, which is connected to the secondary air line (22) by means of a connecting line (34). The regulating valve influences the cross section of the bypass (16) so that the cross section of the bypass can be simultaneously widened when the throttle valve (14) is opened, whereby a pressure drop in the turbine caused by the opening of the throttle valve can be compensated for. In another embodiment, a control valve that is controlled by a control unit can also be mounted, wherein mechanical coupling of the throttle organ in the bypass and the throttle valve is also possible. The disclosed method enables simultaneous regulation of intake air flow and secondary air flow with acceptable structural complications thereby representing an economical solution.

Exhaust gas system

Abstract: An exhaust gas system for converting harmful substances of an exhaust gas of a mobile internal combustion engine includes at least one reducing agent feed, a catalytic converter, a filter element and an exhaust pipe. The reducing agent feed opens into the exhaust pipe upstream of the filter element, while the catalytic converter is disposed downstream of the filter element, as seen in exhaust gas flow direction. Additional components, such as a mixer, a pre-catalytic converter and a heating element, etc. used for purifying exhaust gas, may also be advantageously integrated into the system.

Supercharged internal combustion engine exhaust system

Abstract: An exhaust system for a supercharged internal-combustion engine in which of the exhaust-gas-carrying components, the exhaust gas pipes leading from the cylinder outlets to the turbines, or the turbines, or the turbines and the exhaust gas pipes are arranged jointly in an exhaust-gas-tight housing. Openings in the exhaust-gas-carrying components cause the space formed between the exhaust-gas-carrying components and the housing to be filled with exhaust gas. By way of a bypass pipe which is connected with the space and leads to the turbine, exhaust gas can be blown off from the space. A blow-off valve is arranged in the bypass pipe.

Air/fuel ratio control system and method for fuel vapor purging

Abstract: A system and method for controlling operation of an engine wherein a fuel vapor recovery system is coupled between an air/fuel intake and a fuel supply system. An air/fuel ratio indication is provided by a proportional plus integral feedback controller coupled to a two-state exhaust gas oxygen sensor. In response to the air/fuel ratio indication and a measurement of inducted air flow, a base fuel command is generated. To compensate for purging of fuel vapors, a reference air/fuel ratio is subtracted from the air/fuel ratio indication and the resulting error signal generated. This compensation factor represents a learned value which is directly related to fuel vapor concentration, and it is subtracted from the base fuel command to correct for induction of fuel vapors. At initiation of fuel vapor purging, the rate of purge flow is incremented a predetermined amount with each change in state of the exhaust gas oxygen sensor.