超磁致伸缩喷油器阀口开度建模
Modeling of Valve Opening for Giant Magnetostrictive Injector

设计一种超磁致伸缩喷油器，其特点为超磁致伸缩致动器直接驱动针阀。将整个系统视为单自由度线性系统，建立了系统的动力学方程，求解得到无针阀阀体撞击时的阀口开度表达式。利用初速度分析了撞击对阀口开度的影响，并分析了静止位置和频率比两个可控参数的影响。得到稳态平衡位置要略低于静止位置，才能保证针阀无激励时可靠关闭；频率比高于5时，棒伸长量的95%都用于开启阀口的结论。
A giant magnetostrictive fuel injector is designed with the feature that the valve is driven directly. The whole system is treated as a single degree of freedom linear system, and the dynamics equation of the system is established. The injector needle displacement response without bounce between needle and valve is obtained by solving the dynamics equation. The influence of the bounce is analyzed through initial velocity. And the influence of controlled parameters, the rest position and frequency ratio, are analyzed at the same time. The results demonstrate that the stable equilibrium position must be lower slightly than the resting position so as to ensure the valve close reliably without any excitation, 95% rod elongation are used for opening the valve port when frequency ratio is higher than 5