深海用液压电机泵关键技术的研究

This project studies on the key technologies about two kinds of hydraulic-motor-pump using water and oil as working medium applied in deep sea. The low temperature of seawater in deep sea is simulated using lab facilities and computer, the internal flow field in gap between the rotor and the stator, the electro-magnetic field, and the temperature field of the motor-pump can be studied. Therefore, the design theory and the optimization method of the electric motor which has high rotational speed and high power density will be obtained. Considering rotor eccentricity and variation of the liquid physical parameters of caused by heat and water pressure in the gap，the dynamic pressure effects on dynamic performance of the high-speed rotating rotor immersed in low temperature and high pressure liquid will be studied.On the basis of the analysis of the fluid-solid coupling dynamics, the electromagnetism-machinery-hydraulics force coupling dynamic model of the motor-pump will be established. This can be the theoretical basis for obtaining good dynamic performance of motor-pump， pattern recognizing for troubleshooting and the selection of the types, materials, and the structure parameters of the bearing. Considering the effects of the elastic deformation and the visco-elasticity of material of piston and bore in high speed sliding together,the characteristics of the fluid dynamic and static pressure in the clearance between piston and bore will be studied, the model of hydrodynamic lubrication and lateral bearing capacity of the cylinder bore will be established. Research on the rules and quantitative relation of the suction pressure variation caused by the changing of types, structure, and operating parameters of distributing valve will be done. The design theory and method of the high rotating speed piston pump used in deep sea can be concluded. Finally, the design theory which can meet the requirements of miniature design of the electric motor and the hydraulic pump, the well matching of their performance, and the whole performance optimization of the hydraulic- motor-pump can be obtained. All of above will be verified in the development of the two kinds of improved prototype.

本项目研究深海用(水和液压油)液压电机泵的共性关键技术。模拟深海低温环境,研究电机泵电磁场、温度场和气隙内流场的特点，得出深海用高转速、高功率密度电机的设计理论和方法。研究深海高压低温环境中浸液高速转子偏心间隙内流体动压和热压效应对转子动力学影响，建立偏心间隙内 "电磁-机械-液压"等力耦合的机电动力学模型，为电机泵整体动力学性能设计、故障诊断和轴承结构参数设计及选材提供理论和方法。考虑柱塞泵的柱塞间隙处流体动压、材料弹性变形和粘弹性对柱塞摩擦副受力的影响，建立高滑动速度下柱塞副流体动压润滑和缸孔侧向承载能力模型，研究深海大水深压力环境中典型配流阀结构参数和泵的工作参数影响吸入腔压力变化规律和数量关系，得出深海用高转速柱塞式液压泵的设计理论和方法。最终形成能满足电机和液压泵二者性能良好匹配、达到小型化要求的两种介质液压电机泵整体优化设计理论，并用于两种介质改进样机的研制中以验证之。

液压电机泵是将液压泵嫁接于电机转子内的新型液压元件，具有功率密度高和减振降噪优势，适用于深海及海洋船舶、航空和压力加工等领域，本项目研究深海用液压电机泵关键技术。以双斜盘柱塞式电机泵为研究对象，建立电机泵转子所受单边磁拉力、液压侧向力和摩擦阻力等多种力耦合作用的动力学模型，研究不同同步转速、不同轴承结构形式和不同柱塞数的电机泵转子动力学特性，为液压电机泵总体设计提供理论基础和设计方法。研究浸液转子小间隙内（ η≥0.97）泰勒库特流的阻力矩、流动流态以及传热学特性，提出了适用于小间隙转子阻力矩计算经验公式，得出无量纲阻力矩 Nuω 随 Ta 数的变化规律，即在Ta ≈3.5E+7 时，进入极限湍流状态，并且符合指数规律： Nuω ~ Ta^0.39。转子表面对流换热能力随着转速升高而加强，在雷诺数 Re为330~495内转子表面温度快速下降，通过仿真研究发现该现象源于间隙内的 Taylor 涡开始形成，得出小间隙内浸液电机转子外圆表面积通过油和水两种介质散热的表面传热系数。建立了双斜盘泵配流机构的动力学模型，研究各种结构参数和工作参数对配流特性的影响，尤其是配流阀芯所受离心力对配流特性的影响。以仿真模型和得出的单个柱塞腔的压力响应曲线和输出流量曲线为基础，研究该类型泵流量脉动和侧向力脉动的特点，同时研究了一种通过改变两个斜盘之间周向相位角度的新变量方式。实验研究了与缸体一起高速旋转下旋转配流阀沿径向离心出流的流量系数，研究结果表明，旋转配流阀阀口出流不仅受压差驱动，还受离心力驱动、科氏力的作用，离心力有助于液流沿径向离心出流，且抑制液流的反向流动。通过样机研究得出了适用于深海用液压电机泵的电机设计所需要磁密度、电密度、线负荷和热负荷等多种设计参数。研制了双斜盘阀配流柱塞式液压电机泵样机，额定压力20 MPa， 输出流量300L /min，容积效率达到 96%，样机实验验证了本项目所研究所取得的理论知识和设计方法。本项目研究解决了应用于深海、使用液压油和水等两种介质液压电机泵及液压泵芯关键技术问题。