轴流泵出水流道水力损失试验研究

受导叶出流环量、出水弯管二次流等因素的影响,轴流泵单孔出水流道内为复杂的螺旋流,双孔出水流道左孔流量大于右孔流量,水力损失异常。采用五孔探针准确测定流道断面水流能量,实测分析出水流道水力损失特性,探讨减阻措施。结果表明,出水流道水力损失不符合与流量平方成正比的关系。与等圆出水管相比,渐扩出水流道可以减小水力损失,提高泵装置效率10％～30％;对单孔流道,轴流泵出口环量过大,增大了水力损失, 而微小环量会使水力损失略有减小;对双孔流道,两孔流量不等,存在偏流,水力损失增大。采用微小出流环量或无出流环量后导叶,可减小出水流道水力损失,提高泵装置效率6％-11％。     

Effects of meridional flow passage shape on hydraulic performance of mixed-flow pump impellers

During the process of designing the mixed-flow pump impeller, the meridional flow passage shape directly affects the obtained meridional flow field, which then has an influence on the three-dimensional impeller shape. However, the meridional flow passage shape is too complicated to be described by a simple formula for now. Therefore, reasonable parameter selection for the meridional flow passage is essential to the investigation. In order to explore the effects of the meridional flow passage shape on the impeller design and the hydraulic performance of the mixed-flow pump, the hub and shroud radius ratio (HSRR) of impeller and the outlet diffusion angle (ODA) of outlet zone are selected as the meridional flow passage parameters. 25 mixed-flow pump impellers, with specific speed of 496 under the design condition, are designed with various parameter combinations. Among these impellers, one with HSRR of 1.94 and ODA of 90° is selected to carry out the model test and the obtained experimental results are used to verify accuracies of the head and the hydraulic efficiency predicted by numerical simulation. Based on SIMPLE algorithm and standard k-ε two-equation turbulence model, the three-dimensional steady incompressible Reynolds averaged Navier-Stokes equations are solved and the effects of different parameters on hydraulic performance of mixed-flow pump impellers are analyzed. The analysis results demonstrate that there are optimal values of HSRR and ODA available, so the hydraulic performance and the internal flow of mixed-flow pumps can be improved by selecting appropriate values for the meridional flow passage parameters. The research on these two parameters, HSRR and ODA, has further illustrated influences of the meridional flow passage shape on the hydraulic performance of the mixed-flow pump, and is beneficial to improving the design of the mixed-flow pump impeller.     

液压泵的设计和运行

本文从液压泵相关液压油路的设计、液压泵的安装、液压泵的运行三个方面介绍液压泵在设计和运行中的注意事项,对液压泵的正确使用有一定的指导意义。     

旋涡泵叶轮和流道水力尺寸智能算法研究

旋涡泵内部流动理论不完善,其叶轮和流道水力尺寸计算通常采用相似计算法和经验统计计算法。文中针对这两种方法在应用中存在的诸多局限性,提出了基于人工神经网络的智能算法。该方法既不以寻求相似的模型泵并进行换算为基础,也不以统计方法获取经验数据,而是以现有旋涡泵产品数据为基础,应用神经网络构建旋涡泵性能参数与水力尺寸之间的关系模型,从而实现泵的性能参数与水力尺寸的非线性映射,并利用这一关系模型进行新产品设计。文中介绍了这一方法的基本原理和关键技术,其中包括神经网络的结构设计、模型选择、样本对设计和网络训练等。解决了由于旋涡泵叶轮和流道结构型式繁多、设计中缺乏足够的经验数据支持及缺乏统一的经验统计方法的问题,提供了使不同企业能够有效地利用已有产品开发新产品的统一方法,该方法不仅支持知识重用,而且具有通用性,对提高旋涡泵的设计质量和缩短设计周期具有重要意义。     

Experimental study of the influence of flow passage subtle variation on mixed-flow pump performance

In the mixed-flow pump design, the shape of the flow passage can directly affect the flow capacity and the internal flow, thus influencing hydraulic performance, cavitation performance and operation stability of the mixed-flow pump. However, there is currently a lack of experimental research on the influence mechanism. Therefore, in order to analyze the effects of subtle variations of the flow passage on the mixed-flow pump performance, the frustum cone surface of the end part of inlet contraction flow passage of the mixed-flow pump is processed into a cylindrical surface and a test rig is built to carry out the hydraulic performance experiment. In this experiment, parameters, such as the head, the efficiency, and the shaft power, are measured, and the pressure fluctuation and the noise signal are also collected. The research results suggest that after processing the inlet flow passage, the head of the mixed-flow pump significantly goes down; the best efficiency of the mixed-flow pump drops by approximately 1.5%, the efficiency decreases more significantly under the large flow rate; the shaft power slightly increases under the large flow rate, slightly decreases under the small flow rate. In addition, the pressure fluctuation amplitudes on both the impeller inlet and the diffuser outlet increase significantly with more drastic pressure fluctuations and significantly lower stability of the internal flow of the mixed-flow pump. At the same time, the noise dramatically increases. Overall speaking, the subtle variation of the inlet flow passage leads to a significant change of the mixed-flow pump performance, thus suggesting a special attention to the optimization of flow passage. This paper investigates the influence of the flow passage variation on the mixed-flow pump performance by experiment, which will benefit the optimal design of the flow passage of the mixed-flow pump.     

多功能综合液压泵试验台的研制

研制了飞机液压泵综合测试台,介绍了试验台的组成、工作原理、主要技术方案;主要阐述以计算机控制技术为核心,集状态监测、数据采集处理为一体的液压泵综合测试系统的设计过程,该型试验台工作稳定可靠,能完全满足飞机液压泵性能技术要求。     

工程机械液压泵的正确使用与修复

以工程机械液压系统中广泛使用的直轴斜盘式柱塞泵为主,介绍了工程机械液压系统柱塞泵的正确使用和新的维修方法,该维修方法可供工程机械维修和使用人员在工作中借鉴。     

液压泵常见故障原因及其使用问题探讨

液压泵是液压系统中的＂心脏＂,当液压系统出现问题时,首先想到液压泵。通过对各种液压泵故障的分析,列出了常见故障及产生原因,最后找出解决方法并探讨了液压泵的合理使用。     

A novel high-temperature and high-pressure hydraulic pump based on mononeuron control

Based on structures and characteristics of traditional hydraulic pumps, this paper proposes a novel high-temperature and high-pressure hydraulic pump (HHHP) that can work under 150°C and 28 MPa to overcome problems of traditional high-temperature plunger pumps. The HHHP is designed with the structure of mechanical division and double cylinder parallel. The control signals of two cylinders are two separate triangle waveforms with 90° phase difference. Because the output waveforms of two cylinders have the same characteristics as the control signals, the HHHP can obtain a stable output after two separate waveforms are superposed. A mononeuron self-adaptive PID control algorithm is also improved by modifying parameters K and η. Two improved controllers are used to control the two cylinders, respectively, making two displacements of plungers match each other. Therefore, reduced fluctuations and stable pressure output is obtained. Besides simulation, tests on the built prototype test system are carried out to verify the performance of HHHP. Results show that the improved control approach can limit fluctuations to a lower level and the HHHP system attains good outputs under different signal periods and different pressures.     

基于性能退化数据的航空液压泵可靠性分析

针对某型号的国产航空柱塞式变量液压泵进行研究,探讨航空液压泵的主要故障模式、失效机理和退化参数,然后建立其加速模型,确定加速退化试验方案,在此基础上建立了基于加速退化试验数据的液压泵可靠性预测方法及步骤,并以具体的加速性能退化试验数据为例进行可靠性分析,得出预测的可靠度变化规律。     

液压泵站节能控制的研究与应用

介绍了可使各类液压泵按用液工况实现自动运行的控制方法研究与应用 ,经使用确认该控制方法具有节电率高、减少设备故障、延长设备使用寿命以及安装、使用无须任何调试等优点。     

泵源液压系统压力脉动抑制方法研究

介绍了泵源液压系统振动与噪声产生的原因,分析了液压系统振动与噪声的危害。设计制造了一种基于流体—结构耦合振动的结构共振式液压脉动滤波器,在转运车泵源液压系统压力脉动测试试验平台上进行了2组试验。测试了泵源液压系统实际工况的压力脉动和安装滤波器后系统的压力脉动情况,得出2种试验条件下的液压脉动波动幅度和脉动率。验证了结构共振式液压脉动滤波器的使用效能和不足,为液压系统振动控制提供了新的技术手段。     

混凝土输送泵车专用可降解抗磨液压油的研制

介绍了混凝土泵车专用可降解液压油的研制.它采用Ⅱ类基础油/加氢精制茶油和聚α-烯烃（即PAO）复合而成的基础油和不含ZDDP的复合添加剂调和而成,具有可降解性以及良好的抗磨减阻性能,满足混凝土输送泵车各液压系统苛刻的使用要求,延长了换油期.     

基于粒子滤波和自回归谱的液压泵故障诊断

针对飞机轴向柱塞式液压泵的工作状态监控问题,提出了一种基于液压泵振动信号分析处理的故障诊断新方法。通过对加速度传感器的原始数据序列进行信号建模,利用粒子数优化后的粒子滤波算法进行降噪;根据滤波后信号的自回归谱提取特征值,结合液压泵的故障机理分析其工作状态,实现对液压泵的故障分析和诊断。实验及仿真结果表明,粒子滤波可有效跟随原始信号并滤除噪声干扰,基于粒子滤波和自回归谱的液压泵故障诊断方法能有效地提取故障特征值,实现故障诊断和识别。     

PCY恒压变量泵液压系统四对轧辊缸动矫直机泵站的设计

在现有矫直机的基础上,进行四对轧辊缸动矫直机泵站部分的设计,采用PCY恒压变量轴向柱塞泵液压系统,通过改变流量来保证系统压力的恒定,从而提高系统的效率,达到有效节能的目的。     

Numerical investigation on vibration and noise induced by unsteady flow in an axial-flow pump

Full-scale structural vibration and noise induced by flow in an axial-flow pump was simulated by a hybrid numerical method. An unsteady flow field was solved by a large eddy simulation-based computational fluid dynamics commercial code, Fluent. An experimental validation on pressure fluctuations was performed to impose an appropriate vibration exciting source. The consistency between the computed results and experimental tests were interesting. The modes of the axial-flow pump were computed by the finite element method. After that, the pump vibration and sound field were solved using a coupled vibro-acoustic model. The numerical results indicated that the the blade-passing frequency was the dominant frequency of the vibration acceleration of the pump. This result was consistent with frequency spectral characteristics of unsteady pressure fluctuation. Finally, comparisons of the vibration acceleration between the computed results and the experimental test were conducted. These comparisons validated the computed results. This study shows that using the hybrid numerical method to evaluate the flow-induced vibration and noise generated in an axial-flow pump is feasible.     

基于加速退化数据的航空液压泵剩余寿命预测技术研究

航空液压泵是航空装备的关键件之一。如何很好地预测液压泵的剩余寿命,使得液压泵的有效寿命能够得到更加充分合理地利用,将具有很大的理论价值和经济效益。通过研究某型航空液压泵的失效模式、失效机理和退化参数,确定其加速退化试验方案,建立其加速退化模型,并在此基础上建立了一套基于加速性能退化试验数据的航空液压泵剩余寿命预测方法及步骤,并以该型航空液压泵的加速性能退化试验数据为例对其剩余寿命进行了预测,验证了该方法的正确性和有效性。     

鱼雷罐车润滑液压泵结构优化

320 t鱼雷罐车担负着高炉与炼钢厂之间的铁水运输任务,是钢铁生产链上的重要环节,而润滑液压泵是鱼雷罐车润滑系统的关键部件.本文分析润滑液压泵的常见故障,并提出可行的解决方案.     

基于iSIGHT平台的轴流泵叶片水力性能优化研究

将数值优化技术与CFD流场计算相结合,由数学过程代替设计人员的经验,控制叶片设计修改方向,构建轴流泵叶片自动优化设计平台。以多学科优化软件iSIGHT为基础,以现有优秀的轴流泵叶片模型为研究对象,建立了参数化建模、网格划分、流场计算和数值优化相结合的轴流泵叶片自动优化设计平台。以叶轮效率最高为目标函数,以扬程和汽蚀余量为约束条件,用该平台对设计工况下的初始叶片进行自动优化设计。对比分析优化前后叶片的水力性能,优化后叶片的水力性能有所提高,表明本文采用的自动优化设计方法是有效和可行的。     

基于改进MF-DFA和SSM-FCM的液压泵退化状态识别方法

针对液压泵振动信号通常具有非线性强和信噪比低的特点,提出了一种基于改进多重分形去趋势波动分析(MF-DFA)和半监督马氏距离模糊C均值(SSM-FCM)的液压泵退化状态识别方法。该方法首先引入滑动窗口技术改进传统MF-DFA方法在时间序列数据分割过程中存在的不足,提高MF-DFA方法的计算精度;然后利用改进MF-DFA方法计算液压泵多重分形谱参数,并分析了不同分形谱参数对液压泵退化状态的反映能力,选取奇异指数α_0和广义Hurst指数波动均值Δh(q)作为退化特征量;最后利用半监督马氏距离模糊C均值方法实现了液压泵退化状态识别,并以液压泵实测数据为例验证本文所提方法的有效性。