直喷式柴油机表面辐射噪声频谱分析研究

采用工程法和简易法,运用大气压模拟测试系统,以某四缸柴油机为研究对象,测试计算柴油机整机噪声在81,90,101 kPa海拔下随转速的变化,以及在标准工况下1/3倍频程声压级.分析测试结果表明:表面辐射噪声随转速增加而增大,且随海拔的不同也会增大,缸盖辐射噪声在1 200～1 500 Hz内较大,主要是燃烧噪声所致.

A Spectrum Research on Surface Radiated Noise for DI-diesel Engine

Adopting the project law and simple method, using atmospheric pressure simulation test system, taking some four - cylinder diesel engine as the research object ,diesel engine noise under 81kPa, 90 kPa, 101 kPa elevation along with the rotational speed change, as well as under standard operating mode, 1/3 time frequency spectrum acoustic pressure level are tested and computed. The result indicates that the surface radiated noise increases along with rotational speed and different elevation. The cylinder cover radiated noise in 1 200 - 1 500 Hz is mainly caused by the combustion noise.