为了打破美国“卡脖子”清单中高压柱塞泵关键技术的垄断，针对大型民用飞机C919在航行过程中需要精准控制舵面的要求，基于全空化模型与可压缩模型，对飞机舵面液压系统动力源——高压轴向柱塞泵的内流特性进行了数值模拟，数值结果与试验结果有较高的吻合度。通过分析流量特性，揭示了流量谷值与峰值的产生原因，发现了空化影响流量脉动的方式，提出了抑制柱塞腔空化的方案。研究结果表明倒灌是造成排油流量谷值的主要原因，排油流量峰值即压强超调产生的原因有两点：倒灌液压油的惯性冲击使腔内压强突然增高、倒灌结束后不能及时完全过流造成的憋压使压强超调；揭示了柱塞腔内含气型气泡会吸收“本应的增压”，延长倒灌时间从而降低流量谷值；为了解决抑制柱塞腔空化会降低理论流量的问题，从压降角度出发，创新地联立了柱塞腔流量方程和压降方程，建立了理论流量不可变下抑制柱塞腔空化的数学模型。根据该模型，提出了两种抑制柱塞腔空化且不改变理论流量的措施，研究可以为轴向柱塞泵的研制提供理论方案。

The high-pressure axial piston pump is the power source in the hydraulic system of aircraft control surfaces. To break the monopoly of the key technology for high-pressure piston pumps in the list of the United States, and aim-ing to satisfy the requirement for precise rudder control in the large civil aircraft C919 during navigation, this study conducted numerical simulations and optimization of internal flow characteristics in the pumps based on full cavita-tion models and compressible models. The numerical simulations were validated by a series of experiments. The reasons for the formation of flow valleys and peaks are revealed by analyzing the flow characteristics, the way cavi-tation impacts flow pulsation is discovered, and a method to suppress cavitation in the piston chamber is proposed. Conclusions : Backflow is the main cause of the drainage flow valley. Drainage flow peak (i.e., pressure overshoot) is caused by two reasons: The inertial impact of backflow hydraulic oil causes a sudden increase in cavity pressure, Hold pressure due to untimely and incomplete overflow after the end of the backflow makes the pressure over-shoot; Reveal that gas bubbles in the piston chamber absorb the "intended boost" and prolong the back-up time, thus reducing the flow valley; The mathematical model for suppressing the cavitation of the piston chamber under the invariable theoretical flow rate is established by innovatively coupling the piston chamber flow rate equation and the pressure drop equation from the perspective of pressure drop in order to solve the problem that suppress-ing the cavitation of the piston chamber reduces the theoretical flow rate. Based on the model, two methods are proposed to suppress the cavitation of the piston chamber without changing the theoretical flow rate, and this study can provide theoretical solutions for the development of military axial piston pumps.