Double-cavity shock absorber with high-pressure piston is the core component of the nose landing gear of the carrier-based aircraft, and its fast-extension performance seriously affects the safety of the catapult-assisted takeoff. The design of a carrier-based aircraft in our country is carried out based on the traditional method of fast-extension dynamics, and it is found that the fast-extension capability is larger than designed. This paper analyzes the working principle of the high-pressure piston shock absorber and explains that the high-pressure air cavity pushes the piston rod to extend rapidly, which will cause the cavitation phenomenon in the main oil chamber. Thus, the cavitation in the main oil chamber makes the traditional modeling method of oil-liquid resistance force no longer applicable. Then, the axial force modeling method of shock absorber considering the cavitation effect is proposed. Based on the carrier-based aircraft, the dynamic response of the shock absorber in the process of fast extension is calculated and then it is compared with the calculation results of the traditional dynamic method. It is found that due to the cavitation effect caused by the forced fast extension section of the high-pressure air plug shock absorber, the fast extension work increases by 67.6%, thus, revealing the fast extension mechanism of the double-chamber shock absorber with high-pressure piston and successfully explaining the phenomenon of the fast extension ability exceeding the expectation of the shock absorber.

中文翻译：

---

高压活塞双腔减震器快速伸缩机理研究

带有高压活塞的双腔减震器是舰载机前起落架的核心部件，其快速伸展性能严重影响了弹射器辅助起飞的安全性。基于传统的快速扩展动力学方法，对我国的舰载飞机进行了设计，发现其快速扩展能力要大于设计的能力。本文分析了高压活塞减震器的工作原理，并解释了高压气腔推动活塞杆快速伸展，这将在主油腔内引起气穴现象。因此，主油腔中的气蚀使传统的油液阻力力建模方法不再适用。然后，提出了一种考虑空化效应的减振器轴向力建模方法。以舰载飞机为基础，计算了减振器在快速伸展过程中的动力响应，并将其与传统动力法的计算结果进行了比较。结果发现，由于高压气塞式减震器的强制快速延伸段所引起的气穴效应，使快速延伸功增加了67.6％，从而揭示了双腔减震器的快速延伸机理。高压活塞，并成功地解释了快速延伸能力超出减震器预期的现象。计算了减震器在快速伸展过程中的动力响应，并将其与传统动力法的计算结果进行了比较。结果发现，由于高压气塞式减震器的强制快速延伸段所引起的气穴效应，使快速延伸功增加了67.6％，从而揭示了双腔减震器的快速延伸机理。高压活塞，并成功地解释了快速延伸能力超出减震器预期的现象。计算了减震器在快速伸展过程中的动力响应，并将其与传统动力法的计算结果进行了比较。结果发现，由于高压气塞式减震器的强制快速延伸段所引起的气穴效应，使快速延伸功增加了67.6％，从而揭示了双腔减震器的快速延伸机理。高压活塞，并成功地解释了快速延伸能力超出减震器预期的现象。