| 摘要:基于SC7H涡轮增压柴油机试验台架，开展了变海拔典型工况下的稳态试验，研究了最大扭矩点(1 400 r/min)和标定转速点(2 300 r/min)分别在循环喷油量25 mg和75 mg工况下，缸内压力、燃烧放热率和燃烧特征参数随海拔的变化规律。研究结果显示:随着海拔的升高，各工况下的最高燃烧压力均呈现下降趋势，最高燃烧压力相位、燃烧始点和燃烧重心推迟，燃烧持续期延长，且低负荷工况受海拔的影响更明显；当海拔升高时，最大压力升高率和最大瞬时放热率在低负荷工况下随之上升，而在高负荷工况下呈下降趋势。 |
| 关键词: 柴油机 涡轮增压 海拔 燃烧特性 |
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| Research on the Combustion Characteristics of a Diesel Engine at Varied Altitudes |
| Yang Kai,Zhang Zhimou,Cheng Jianghua,Liu Sheng,Zhang Huiyan,Shi Lei |
| Key Laboratory for Power Machinery and Engineering of Ministry of Education,Shanghai Jiao Tong University,Shanghai 200240;China North Engine Research Institute, Tianjin 300300 |
| Abstract:Based on SC7H turbocharged diesel engine test bench, steady state tests at varied altitudes were carried out. The influence of altitude on cylinder pressure, combustion heat release rate and combustion characteristic parameters at the maximum torque point (1 400 r/min) and the calibrated speed point (2 300 r/min) with 25 mg and 75 mg cycle fuel injection quantity was studied. The results show that with the increase of altitude, the maximum combustion pressure shows a downward trend under all working conditions. The position of maximum combustion pressure, the starting point of combustion and the combustion center of gravity are postponed, the combustion duration is prolonged. The effect of altitude under low load condition is more significant. With increasing altitude, the maximum pressure rise rate and maximum instantaneous heat release rate increase under low load condition, and decrease under high load condition. |
| Key words: diesel engine turbocharging altitude combustion characteristic |
