Cavity resonance-based control method for reducing combustion noises of combustion engines

Abstract

The invention belongs to the technical field of combustion engines, and relates to a cavity resonance-based control method for reducing combustion noises of the combustion engines. The control method comprises the following steps: performing an phonics response experiment to a combustion chamber of a selected combustion engine to determine a combustion chamber cavity resonance frequency range corresponding to different crank shaft rotor angles of the combustion engine, inputting the frequency range to a ECU (Electronic Control Unit) of the combustion engine for use during the operating process of the combustion engine in an MAP (map analyzer program) manner; during the operating process of the combustion engine, performing on-line high frequency filtering on the high frequency pressure oscillation data in a time window according to the measured air cylinder pressure signals, and using a wavelet analyzing method to acquire the combustion chamber cavity resonance frequency corresponding to different crank shaft rotor angles; and further, comparing combustion chamber cavity resonance frequencies corresponding to different crank shaft rotor angles with the combustion chamber cavity resonance MAP corresponding to different crank shaft rotor angles in the ECU, and taking corresponding measures to reduce the cylinder high frequency pressure oscillation of a ring. The cavity resonance-based control method for reducing the combustion noises of the combustion engines can effectively reduce the combustion noises of the combustion engines, especially small combustion engines.

Description

Technical field [0001] The invention relates to a control method for reducing combustion noise of an internal combustion engine based on cavity resonance, in particular to a control method for reducing combustion noise of a miniaturized internal combustion engine. Background technique [0002] Among urban noise pollution, 75% comes from traffic noise with internal combustion engines as the main noise source. Noise pollution has caused great impact and harm to people's quality of life, physical and mental health. The internal combustion engine is a complex machine with multiple sound sources. Due to the difference in the structure, size and operating conditions of the internal combustion engine, the impact of each sound source on the total noise is also different, and the combustion noise occupies a large proportion of the total noise of the internal combustion engine. [0003] Generally speaking, combustion noise refers to the high-frequency oscillation of pressure caused b...

AI Technical Summary

Problems solved by technology

Although the relationship between the in-cylinder pressure oscillation and the cavity resonance of the combustion chamber has been recognized traditionally, and the structure of the combustion chamber of the internal combustion engine has been optimized from the perspective of propagation path to avoid these resonance frequencies; Change the working parameters of the internal combustion engine (ignition timing, fuel injection timing, etc.) to reduce high-frequency pressure oscillations in the cylinder, thereby reducing combustion noise

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