| 摘要:基于某船用柴油机单缸试验机的试验缸压曲线，采用频谱分析的方法，建立缸压曲线和燃烧噪声之间的关系。根据柴油机的燃烧过程，将缸压曲线分解为倒拖缸压、燃烧振荡压力和“剩余”燃烧压力曲线。分析发现:在全负荷工况，10～300 Hz低频声压值主要由倒拖缸压决定；1.8～20 kHz高频声压值主要由燃烧振荡压力决定；0.3～1.8 kHz中高频声压值主要由“剩余”燃烧压力决定。分析表明:喷油正时提前，中低频的声压值增大，高频声压值略有增大；柴油机转速上升，全频段的声压值均增大；负荷越大，10～600 Hz的声压值越大，对2～20 kHz的高频燃烧噪声影响较小。 |
| 关键词: 船用柴油机 缸压曲线 频谱分析 燃烧噪声 |
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| Marine Diesel Engine Combustion Noise Analysis Based on Experimental In-Cylinder Pressure Curve |
| Mao Jinlong,Zhang Wenzheng,Li Xiannan,Huang Li |
| Shanghai Marine Diesel Engine Research Institute, Shanghai 201108 |
| Abstract:Based on the experimental in-cylinder pressure curves got from a marine diesel engine's single cylinder test bench, the relationship of in-cylinder pressure curve and combustion noise was analyzed using frequency spectrum analysis method. According to the phenomenon during diesel engine working process, the in-cylinder pressure was decomposed to the motored pressure, the resonance excitation pre-ssure and the remained combustion pressure. The analysis results show that at full load condition, the motored pressure mainly affects the sound pressure level (SPL) of 10~300 Hz; the resonance excitation pressure mainly affects the SPL of 1.8~20 kHz; and the remained combustion pressure mainly affects the SPL of 0.3~1.8 kHz. Analysis showed that, the SPL of low and medium frequency would increase while the injection timing was advanced and the SPL of high frequency would also increase a little; the SPL of whole frequency range would increase while the diesel engine speed increased; the SPL of 10~600 Hz would increase while the engine load increased and the SPL of 2~20 kHz would increase little. |
| Key words: marine diesel engine in-cylinder pressure curve frequency spectrum analysis combustion noise |
