Control method for reducing engine oil dilution level of in-cylinder direct injection gasoline engine

Abstract

The invention discloses a control method for reducing the engine oil dilution level of an in-cylinder direct injection gasoline engine. The control method for reducing the engine oil dilution level ofthe in-cylinder direct injection gasoline engine comprises the following steps that (1) source control of liquid gasoline is carried out, specifically, the structure of a combustion system of the in-cylinder direct injection gasoline engine and an oil injection control strategy are optimized; (2) source control of gaseous gasoline is carried out, specifically, the matching structure of a piston gas ring and a cylinder bore is optimized; (3) enhanced precipitation control of gaseous gasoline is carried out, specifically, cooling intensity of an engine oil cooler is optimized; and (4) enhancedrecovery control of gaseous gasoline is carried out, specifically, a crankcase ventilation system is optimized, and the separation effect of an oil-gas separator is enhanced. The control method for reducing the engine oil dilution level of the in-cylinder direct injection gasoline engine can effectively control the engine oil dilution level at all rotating speeds and load working points of the engine, and eliminates the risk of poor lubrication or even damage of the engine.

Description

technical field [0001] The invention belongs to automobile components, in particular to a control method for reducing the oil dilution level of direct-injection gasoline engines in cylinders. Background technique [0002] Gasoline direct injection technology and its combination with exhaust gas turbocharging technology have become the mainstream technology widely used in the current domestic and foreign automobile industries, which greatly improves engine power and reduces fuel consumption and emissions. However, after the direct injection technology is applied, the liquid gasoline directly injected into the gasoline engine cylinder is likely to adhere to the cylinder wall after colliding with the cylinder wall. During the working process of the gasoline engine, together with the lubricating oil on the cylinder wall With the scraping effect of the piston oil ring, it enters the oil pan, causing gasoline to dilute the engine oil. After the engine oil is diluted by gasoline, ...

AI Technical Summary

Problems solved by technology

Existing Oil Dilution Control Methods Have Significant Drawbacks

First of all, the mechanical structure of the combustion system determined through structural optimization, due to the wide range of speed and load of the gasoline engine, the range of fuel injection quality of each working cycle at different operating points is also very large, and it is impossible to make each working cycle of the gasoline engine at the same time. All operating points have the lowest amount of wall-impacting fuel, and the oil dilution level at medium-to-high-speed and medium-to-high-load operating points is still relatively high; secondly, for the electronic control optimization method of fuel injection strategy, with the increase of the speed and load of the gasoline engine (engine The absolute time of each working cycle is shortened, the fuel injection volume is greatly increased, and the direction and intensity of airflow in the cylinder are greatly changed), its dynamic optimization potential for spray movement will be greatly reduced, and gasoline engines still have high Oil dilution level, needs to be further optimized

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