压电喷油器结构参数优化及性能试验研究

压电执行器由于其快速准确的动态响应特性,为喷油器精确的小油量、多次喷射能力提供了重要保障。针对研制的压电喷油器,基于压电喷油器一维电-机-液耦合仿真模型,进行了喷油器关键结构参数优化设计,并对研制出的喷油器性能进行测试,从油量特性、响应特性以及多次喷射过程的喷油规律等方面验证了喷油器的可靠性。结果表明:相比于初定方案,优化后喷油器响应特性有所改善,喷油量略微减少,针阀的开启延迟减少了0.04 ms,关闭延迟减少了0.05 ms,抬起时间缩短了0.29 ms,落座时间缩短了0.17 ms;试验表明该喷油器油量稳定性较好,最小预喷油量为4 mm3,能够实现小油量的预喷和波形稳定的多次喷射。

Structure Parameter Optimization and Performance Test of Piezoelectric Injector

Piezoelectric actuator provides an important guarantee for precise small-quantity and multiple injection capability of injector due to its fast and accurate dynamic response characteristics. The key structural parameters of the injector were optimized based on an one-dimensional electro-mechanical-hydraulic coupling simulation model of the piezoelectric injector. The performance of the developed injector was tested. The reliability of the injector was verified from the aspects of fuel quantity characteristics, response characteristics and the injection rate curves of multiple injection processes. The results show that compared with the initial scheme, the response characteristics of the optimized injector are improved, the injection volume is slightly reduced, the opening delay of needle valve is reduced by 0.04 ms, the closing delay is reduced by 0.05 ms, the lifting time is shortened by 0.29 ms, and the setting time is shortened by 0.17 ms. The test shows that the injector has good stability of fuel volume, and the minimum pre-injection volume is 4 mm 3, which can realize pilot injection with small quantity and multiple injections with stable waveform.