柴油物性对单体泵性能影响规律的数值研究

摘要

The numerical model of electronic control unit pump was built with AMESim software and was calibrated ,the accu-racy of simulation model was verified and the influence of diesel property on EUP injection characteristic was researched .The results show that the physical properties of different diesels have slight influence on high-pressure tubing pressure curve ,but have strong influence on average high-pressure tubing pressure and cycle fuel injection quantity .When all physical properties are constant under the reference pressure ,the calculation error decreases with the increase of engine speed .The influences of three constant property settings on simulation results are further analyzed .It is found that the effect of density is the least and even can be ignored ,bulk modulus is secondly less ,and viscosity is the greatest .%利用AM ESim软件建立了电控单体泵的数值模型，进行了仿真模型标定，验证了仿真模型的准确性，研究了柴油物性的变化对电控单体泵供油特性仿真计算的影响。计算结果表明：不同种类柴油物性随压力变化时对高压油管压力曲线形状影响较小，但对平均高压油管压力和循环喷油量影响较大；将柴油物性设置为参考压力下的定值时，随着转速增加计算误差减小。分析了将3种柴油物性分别设置为定值时对仿真计算的影响，研究结果表明：在参考压力下将柴油密度设为定值对仿真计算结果的影响最小，可以忽略；体积模量设为定值时误差较小；运动黏度设为定值时计算误差最大。