Homogeneous charge compression ignition (HCCI) and traditional combustion combined operating method for engine

Abstract

The invention discloses a homogeneous charge compression ignition (HCCI) and traditional combustion combined operating device and an HCCI and traditional combustion combined operating method for an engine. The HCCI and traditional combustion combined operating device comprises an HCCI working cylinder group, a traditional combustion working cylinder group and a mechanical supercharger, wherein an air outlet end of the mechanical supercharger is connected with an inlet of an air inlet header pipe; an outlet end of the air inlet header pipe is respectively connected with the air inlet ends of a first air inlet branch pipe and a second air inlet branch pipe; a first mechanical supercharging control valve and a second mechanical supercharging control valve are respectively arranged at the inlet ends of the first and second air inlet branch pipes; the air outlet ends of the first and second air inlet branch pipes are respectively connected with the air inlets of the HCCI working cylinder group and the traditional combustion working cylinder group; the waste gas exhaust ports of the HCCI working cylinder group and the traditional combustion working cylinder group are respectively connected with the air inlets of the first and second exhaust pipes; a first turbocharger is arranged on a first air outlet / inlet branch pipe; and a second turbocharger is arranged on a second air outlet / inlet branch pipe. According to the device and the method, the range of the operating conditions of the HCCI is obviously widened, and the high-efficiency clean combustion advantages of the HCCI are maximized.

Description

technical field [0001] The invention relates to the field of internal combustion engines, in particular to a combustion mode and a control method for realizing combined operation of engine homogeneous compression ignition and traditional combustion through cylinder division control. Background technique [0002] Homogeneous compression ignition (HCCI) refers to the process in which the premixed gas formed by fuel, air and recirculated combustion products is compressed by the piston, spontaneously ignites, ignites, and performs work. Under the background of stricter internal combustion engine exhaust emission and carbon dioxide emission regulations and global energy shortage, HCCI can not only obtain extremely low nitrogen oxide and particulate emissions, but also obtain higher thermal efficiency than diesel engines, so it is considered as the traditional compressor. Alternative combustion methods for the future of combustion ignition (CI) and spark ignition (SI) internal com...

AI Technical Summary

Problems solved by technology

There are two main problems in the current dual-mode operation mode: first, the structure and control strategy of the internal combustion engine need to take into account the combustion characteristics of the traditional combustion mode and the HCCI mode, which limits the advantages of the HCCI combustion process

For example, in the SI-HCCI dual-mode engine, in order to take into account the SI combustion characteristics, the compression ratio of the engine is limited, which reduces the maximum thermal efficiency of the HCCI operating condition; in the CI-HCCI dual-mode engine, in order to take into account the CI combustion characteristics, Limits modifications to engine injector and combustion chamber structures, thereby reducing the range of operating conditions in which HCCI can operate

Second, the current dual-mode operation needs to be completed within several ignition cycles during the switching process between the traditional combustion mode and the HCCI mode, and the smooth and fast combustion mode switching significantly increases the complexity of the engine control system

It can be seen that, since CI-HCCI dual-mode engines are all compression auto-ignition, the combustion mode conversion is relatively easy, but in expanding the range of HCCI operating conditions, the structural modification and control strategy for HCCI will often lead to the failure of the engine under the traditional combustion mode. Performance deterioration

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