Gasoline supercharged engine exhaust gas recirculation system device

Abstract

The invention discloses a gasoline turbocharged engine exhaust gas recirculation system device which comprises a cylinder cover; the exhaust side of the cylinder cover is provided with an exhaust manifold, and the gas inlet side is provided with a gas inlet manifold; the exhaust manifold is connected with a turbocharged system; an EGR gas inlet pipe is connected to the side of the exhaust manifold; the other end of the EGR gas inlet pipe is sequentially connected with an EGR valve, an EGR cooler and the gas inlet manifold; the cylinder cover is further provided with an EGR gas inlet water sleeve; and the EGR gas inlet pipe is wrapped with the EGR gas inlet water sleeve. The gasoline turbocharged engine exhaust gas recirculation system device greatly lowers the exhaust gas temperature before the EGR valve, reduces the size of the EGR system device, enables the exhaust gas content ratio in the gas inlet manifold to be higher and the EGR ratio to be higher as the gas inlet temperature ofEGR is lower at the same time and is beneficial to further inhibiting detonation and improving the fuel efficiency; in addition, the outlet pressure on the EGR gas inlet side is small in loss and is higher than the pressure on the gas inlet side of the turbocharged system, so that the EGR system is smooth in gas inlet, and the working condition range capable of running EGR by an engine is larger;and the exhaust gas storage quantity of the EGR gas inlet pipe is less, so that the regulation response time of the EGR valve is prolonged.

Description

technical field [0001] The invention relates to the technical field of engines, in particular to an exhaust gas recirculation system device of a gasoline supercharged engine. Background technique [0002] Engine exhaust gas recirculation technology (EGR) refers to the technology that reintroduces part of the exhaust gas from the exhaust side of the engine to the intake side to mix with fresh air and participate in combustion. After the exhaust gas recirculation technology mixes the cooled exhaust gas with fresh air, it makes The oxygen content in the mixed gas is reduced, which reduces the combustion temperature of the combustion chamber, thus suppressing the generation of NOx. [0003] For gasoline engines, when the engine load is small, the throttle opening is small, and the pumping loss is relatively large at this time. When using external EGR technology at low load, in order to maintain sufficient fresh air intake, the throttle opening must be increased, thereby reducin...

AI Technical Summary

Problems solved by technology

[0004] The existing exhaust gas recirculation system is generally combined with the engine supercharging system. For example, Chinese patent CN106762238A discloses a low-pressure exhaust gas recirculation system based on a supercharged engine. This system sets the gas intake position of EGR in the supercharging system After the turbine and catalytic converter, the pressure of the exhaust gas becomes smaller, so that the operating range of the EGR system can be reduced; and the exhaust gas is cooled by the EGR cooler first, and then passes through the EGR valve, so that the pipe path of the exhaust gas before the EGR valve is shorter. Long, the response time of EGR valve adjustment becomes longer, which is not conducive to precise control of exhaust gas circulation

[0005] Chinese patent CN108730073A discloses a high-pressure exhaust gas recirculation system for a supercharged diesel engine. In this system, the gas intake position of EGR is set before the turbine, but the EGR valve is set after the EGR cooler, and the adjustment response time of the EGR valve is still long. , the control accuracy is low, and because the EGR system is not equipped with a catalytic converter, the residual gasoline vapor in the exhaust gas is easy to block the EGR valve after cooling; Chinese patent CN203717168U discloses an engine and its exhaust gas recirculation system, exhaust manifold

In this system, the EGR intake position is set before the turbine, and the EGR valve is set before the EGR cooler. However, since the temperature of the exhaust gas discharged from the exhaust manifold is generally as high as 800°C to 900°C, it is easy to affect the structural reliability of the EGR valve.

Images