EGR (exhaust gas recirculation) cooler and engine

Abstract

The invention discloses an EGR cooler comprising a shell, a heat exchange tube stack, an end cap and an adjusting device. The adjusting device comprises a rotary driving portion and a rotary plate in drive connection with the rotary driving portion, and the rotary plate is provided with a first waste gas via hole. The end cap comprises a cap body and an adjusting plate fixed to the cap body, the cap body is provided with a waste gas inlet communicated with the first waste gas via hole, multiple second waste gas via holes are formed in the adjusting plate and respectively communicated with multiple heat exchange tube bundles arranged in the heat exchange tube stack and unequal in heat exchange area, the rotary plate has a rotary stroke relative to the adjusting plate, and in the rotary stroke of the rotary plate, the first waste gas via hole is communicated with the second waste gas via holes in sequence. The EGR cooler is compatible to two operating conditions of low exhaust temperature and small EGR rate and high exhaust temperature and large EGR rate, temperature of cooled waste gas is more accurately controlled according to the different operating conditions, and arrangement of internal parts of an engine is facilitated. The invention further discloses the engine.

Description

technical field [0001] The invention relates to the technical field of engine structure design, in particular to an EGR cooler. The invention also relates to an engine. Background technique [0002] The engine cools the EGR system (Exhaust Gas Recirculation System) to reintroduce part of the exhaust gas (recirculated exhaust gas) into the cylinder to participate in combustion, so as to reduce NOx emissions. Usually this part of the recirculated exhaust gas will be cooled by the EGR cooler, so as to better reduce the combustion temperature in the cylinder (high temperature is a necessary condition for generating NOx, cold EGR reduces the combustion temperature through its own lower temperature on the one hand, and the other On the one hand, the polymer gas in the exhaust gas has a large heat capacity and will absorb part of the heat), so the EGR cooler is currently a device commonly used in engines with emission levels of China IV and above. [0003] Since the engine has di...

AI Technical Summary

Problems solved by technology

Although this EGR cooler with bypass pipeline can solve the contradiction between high temperature and low temperature operating point, it still has great limitations: on the one hand, this method is not accurate enough for the temperature control of the cooled gas, whether the exhaust gas The cooling through the cooler can only be controlled by a "one size fits all" bypass valve; on the other hand, it is difficult to arrange the bypass EGR cooler on the engine. Integrated with the EGR valve, coupled with the bypass line, often makes the layout more tense

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