生物柴油分子结构对柴油机喷射特性的影响研究

Research on the influence of biodiesel molecular structure on diesel injection characteristic

利用HYDSIM软件建立高压共轨喷油器仿真模型,对生物柴油中几种脂肪酸甲酯的喷射过程进行仿真分析。研究结果表明:与短碳链的月桂酸甲酯相比,长碳链的硬酯酸甲酯的最大喷油速率、循环喷油量和循环喷射能量均较大,喷油终点延后。与不含双键的硬脂酸甲酯相比,含一个双键的油酸甲酯的最大喷油速率、循环喷油量和循环喷射能量均较小,喷油终点提前,喷油始点差别不明显。与几种脂肪酸甲酯相比,石化柴油的最大喷油速率最小,喷油终点最靠前;虽然其循环喷油量最小,但其循环喷射能量却仅次于硬酯酸甲酯,高于月桂酸甲酯和油酸甲酯。

Biodiesel is a mixture composed of a variety of fatty acid methyl esters.The model of common rail injector is established using HYDSIM and the injection process of fatty acid methyl ester is discussed.The results show that compared with methyl laurate,the maximum injection rate,injection quantity and injection energy per cycle for methyl stearate（long carbon chain）is larger.Injection ends late.Compared with the methyl stearate,the maximum injection rate,injection quantity and injection energy per cycle for methyl oleate（contain a double bond）are little,injection ends advance,the difference between injection starting is not obvious.Compared with fatty acid methyl ester,maximum injection rate of petrodiesel is the smallest.Although its fuel injection quantity per cycle is the smallest,but its injection energy is higher than that of methyl ester and methyl oleate.