论文部分内容阅读
喷雾场的温度对燃油的蒸发，混合气的形成，着火以及火焰传播有着决定性影响。在进行数学模拟时，雾场温度是很重要但很难测量的参数，迄今尚少有直接测量结果的报道。本文用薄膜式热电偶测量了柴油机高压喷雾雾场内的温度随时间的变化。热电偶经氩离子脉冲激光器标定，其时间常数约为６０‘μｓ。燃油喷射压力为１０２ＭＰａ～１３４ＭＰａ。测量结果表明，在本实验条件下，雾场内的温度与环境气体温度相差只有８Ｋ～３０Ｋ左右，比预计值要小很多。而且，环境温度较高时，雾场内外温度差减小。这可能是由于热管效应的作用。喷油压力对雾场内外温差没有明显影响，雾场外围处比雾场中心处与环境的温差要小。近喷嘴处的温度测量值随时间单调下降，且与环境温度相差较大，表明此处燃油沉积作用比较明显。
The temperature of the spray field has a decisive influence on the evaporation of the fuel, the formation of the gas mixture, the ignition and the spread of the flame. Fog field temperature is a very important parameter that is difficult to measure during mathematical simulation. So far, there are few reports of direct measurement results. In this paper, the temperature change of diesel engine high pressure spray fog field with time was measured by thin-film thermocouple. Thermocouple argon ion pulse laser calibration, the time constant of about 60’μs. Fuel injection pressure of 102MPa ~ 134MPa. The measurement results show that under the experimental conditions, the difference between the temperature in the fog field and the temperature of the ambient gas is only about 8K ~ 30K, much smaller than the expected value. Moreover, when the ambient temperature is high, the temperature difference between inside and outside the fog field decreases. This may be due to the heat pipe effect. The injection pressure had no significant effect on the temperature difference between the inside and outside of the fog field. The temperature difference at the periphery of the fog field should be smaller than the temperature at the center of the fog field. Near the nozzle at the temperature measurement monotonous decline over time, and a large difference with the ambient temperature, indicating that the role of fuel deposition more obvious here.