| 摘要:针对波动高背压环境下的柴油机性能异化问题开展背压对柴油机性能影响规律研究，构建波动高背压环境的船用柴油机性能预测模型，并基于试验测量结果进行标定。基于该模型研究在不同背压环境下柴油机性能与关键参数的变化规律。结果表明：高背压显著影响柴油机输出功率，在背压为165 kPa时降幅高达69%，且排温快速达到限制值；在背压波动工况下，柴油机性能及运行参数呈现出围绕准稳态性能的迟滞环特征，该非定常迟滞效应在波动周期及背压时均值降低时均明显强化。柴油机配气系统内流体的气动惯性及涡前能量对背压的敏感度差异是造成在背压波动工况下柴油机性能迟滞效应的原因。 |
| 关键词: 柴油机 波动高背压 性能异化 性能迟滞 |
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| Performance of Diesel Engine With Fluctuating High Exhaust Backpressure |
| WANG Ziyi,MA Zetai,YANG Mingyang,DENG Kangyao |
| Key Laboratory for Power Machinery & Engineering of Ministry of Education， Shanghai Jiao Tong University， Shanghai 200240，China |
| Abstract:In response to the deterioration of diesel engine performance under fluctuating high exhaust backpressure，the influence law of backpressure on engine performance was studied.The performance prediction model of marine diesel engine in fluctuating high exhaust backpressure was established and calibrated with test data.Based on this model，the variation laws of engine performance and key parameters under different backpressure environment were studied.The results showed that：High exhaust backpressure significantly influences engine output，which can be reduced by up to 69% at 165 kPa，and exhaust temperature rapidly reaches the limit value；Under fluctuating backpressure condition，the performance and operating parameters of the diesel engine show hysteresis loops characteristics around the quasi-steady performance，and the unsteady hysteresis effect expands during the fluctuating period and when time-weighted backpressure decreases.The aerodynamic inertia of fluid inside the diesel engine gas system and the difference of sensitivity of available energy before turbine to backpressure are the reasons of diesel engine performance hysteresis phenomenon under fluctuating backpressure condition. |
| Key words: diesel engine fluctuating high exhaust backpressure performance deterioration performance hysteresis |
