大型空气分离装置双泵内压缩流程工艺创新

对空分设备采用的内压缩流程和外压缩流程进行了阐述,分析了目前运行的双泵内压缩装置的缺点,在降低蒸汽消耗、调整负荷、调配高压空气量、气源改造、降低CO2含量等方面进了创新探索.实际运行表明改造措施合理,在生产运行中取得了良好效果.     

顶吸式真空引水罐的改造设计及应用

传统的排气引水装置,不论是带底阀还是不带底阀,一方面都要求水泵及吸水管路很严密,不存在漏气的部位,在操作中必须对水泵和真空泵泵轴的填料函进行经常性地调整,直接影响排气引水时间;另一方面装置容易引起漏气,须经常检修拆换,给使用带来不便.针对这种情况,对大余县供水公司在引水装置方面进行了改造,经过多年运行实践效果良好.     

华能上安电厂4#机组循环水泵节能改造理论与应用

对华能上安电厂4#机组的循环水泵进行了节能改造,增大了叶轮的出口宽度,采用了较大的叶轮叶片出、入口宽度比和较小的叶片包角;为了提高泵的水力效率,泵壳体采用流线型设计,同时加大了壳体的通流面积.改造后取得了预期的效果,同改造前相比,4A泵、4B泵效率分别提高了11.20%和13.38%,总输入功率减少了576.3 kW,运行2年即可收回改造投资.     

基于FIFO恒压供水系统的泵组控制

在恒压供水系统中,泵组的控制属于较大范围的自适应系统,泵组的平衡运行是自动调整系统运行参数的关键.通过对微机控制的恒压供水系统中泵组各种工作状态与变压供水关系的分析,提出了一种"FIFO" 泵组控制方式,并详细阐述了其软件设计的思想,运行结果满足了"FIFO"的控制要求.     

粒子群算法在带导叶离心泵性能优化中的应用

为了提高带导叶离心泵运行效率和解决泵性能优化过程中优化目标与设计变量间强非线性问题,文中提出了一种基于粒子群算法的叶轮多参数智能优化方法.在Workbench软件平台搭建了叶轮造型、网格划分和性能计算的数值仿真流程.以泵设计流量效率为优化目标,定义扬程为约束条件,通过Bézier曲线控制叶片安放角、叶片进口边位置和叶片...     

立式混流泵装置压力脉动的模型试验分析

为研究立式混流泵装置内部压力脉动特性,通过模型试验的方法,对某混流泵装置不同叶轮叶片安放角(-2°、0°、2°)下叶轮进口和导叶出口的压力脉动进行采集,通过傅里叶变换后比较分析得出:混流泵装置叶轮进口和导叶出口压力脉动峰峰值均具有一定的规律性,不同叶片安放角下叶轮进口压力脉动峰峰值均大于导叶出口,小流量区域表现得更为明显;建立了泵装置稳定性微观与宏观间的联系,得出高效区附近可以通过压力脉动来反映机组波动性;叶轮进口压力脉动受叶片数的影响,主要以叶频为主,导叶出口压力脉动在1倍转频处幅值最大,受导叶片数影响不大;混流泵装置最优运行区域为最优扬程的0.75~1.15倍区域,运行扬程超出这个范围,压力脉动峰峰值明显增大。     

减摇鳍装置的鳍角限位问题

本文论述了在减摇鳍装置上采用的两类液压驱动系统中的最大位置输出的限位问题.其中以泵控制系统为主说明各种液压限位装置的工作原理和特点,对它们在系统运行时投入工作的时机进行了分析.最后,讨论了怎样把泵控制系统限位的一些方法扩充应用到阀控制系统中去.     

叶片数对离心泵空化诱导振动噪声的影响

为研究叶片数对离心泵空化诱导振动噪声的影响,以一台5叶片单级端吸离心泵为研究对象,保持泵体和叶轮其他几何参数不变,将叶片数分别改为4、6和7.基于虚拟仪器数据采集系统和泵产品测试系统在离心泵闭式实验台上测量了不同叶片数模型泵在不同净正吸入水头(NPSH)时的振动、噪声和出口压力脉动信号,并对信号进行处理和分析.试验结果表明:模型泵空化诱导的振动对泵体的影响最大,综合比较各测点的振动强度,4叶片模型泵的振动最剧烈,5叶片模型泵的振动相对最小.在不同空化状态下,模型泵噪声信号随叶片数的增加叶频峰值基本不变,但轴频峰值变化规律复杂,在空化严重时,6叶片模型泵的轴频峰值最大.随着空化程度的加剧,各叶片数模型泵的轴频峰值呈下降趋势.     

白沙滩泵站叶片调节机组运行优化

利用白沙滩泵站混流泵叶片角度可调的优势,结合泵站内外水位资料和不同运行期规定的提水量,以机组总耗电量最小为目标函数,建立了以叶片角度为决策变量的机组运行优化调度模型.运用一维离散型动态规划算法求解,得到各运行期泵站的开机台数、水泵叶片安放角、单台泵流量等.与按该站水泵设计角-2°运行相比,泵站采用该优化方案,年均可节省电能454.7万kW.h,节省电费184.1万元,节约率约为15%.可见,该方案节能效果显著,能有效降低泵站运行成本.     

射流泵装置流体过渡过程的研究

本文首次将射流泵全特性曲线运用于射流泵装置流体过渡过程的数值计算中，在分析射流泵装置的瞬变运行工作参数随时间变化的同时，着重就射流泵全特性曲线对装置特性的影响进行了研究。计算和分析结果可供工程设计参考。     

机械式全调节水泵抬机及其原因分析

抬机是水泵运转中经常出现的故障之一,发生机理较为复杂,影响因素很多,如进水池的水位变幅突然增大等.机械式全调节水泵在某些工况运行时因机械调节机构本身的原因也会发生抬机,尤其是往正角方向调节叶片角度时.从受力分析角度出发,以16CJ-80型机械式全调节水泵为例,对其叶片系统进行详细的受力分析,针对不调叶片安放角、往正角方向调、往负角方向调3种情况进行力学计算.经对比分析,得出结论:机械式叶片调节机构的受力方式是引发抬机的一个内因,机组推力轴承受力的突变是引发机组抬机的根本原因.因此,改善机械式叶片调节机构的受力,可以有效解决水泵机组的抬机问题.     

动叶轮叶片数对多相混输泵水力性能的影响

为了探究动叶轮叶片数对多相混输泵外特性、做功性能和水力特性的影响规律,基于欧拉非均质流模型,利用CFX软件对不同动叶轮叶片数下的多相混输泵在多种流量工况、入口含气率10%的条件下进行数值计算。研究发现:流量在90 m3/h及以下时,动叶轮叶片数对扬程和效率的变化趋势影响相对较小,而随着流量的增加,四叶片动叶轮会使混输泵扬程和效率的下降程度增大;当动叶轮叶片数为3时,多相混输泵的外特性、叶片表面静压分布、载荷分布和水力特性等均优于动叶轮叶片数为4时的性能。本文的研究结果可为多相混输泵动叶轮叶片数的选择提供参考。     

Effects of blade rotation angle deviations on mixed-flow pump hydraulic performance

By model test and numerical simulation,this paper analyzed the effects of different blades with varying rotation angle deviations on the hydraulic performance of a mixed-flow pump.It was found that when some blades had rotation angle deviations,the hydraulic performance curves of the mixed-flow pump would move.With a positive deviation,the curves moved towards the large flow rate;with a negative deviation,the curves moved towards the small flow rate.When some blades had rotation angle deviations,the symmetry and uniformity of the pressure distribution inside the mixed-flow pump flow passage both decreased;the larger the deviation,the greater the decrease.When a single blade had a large rotation angle deviation,a rather clear low pressure area was formed,lowering the cavitation performance.When two adjacent blades changed simultaneously,under the small flow rate condition,adverse pressure gradient and flow separation occurred in the flow field,and a hump appeared in the head curve and the operation stability of the mixed-flow pump dropped significantly.Near the best efficiency point(BEP),the simultaneous change of two alternate blades produced a more significant change of pressure in the flow passage,with an even larger area.Compared to the effect of two adjacent blades,two alternate blades,when changed simultaneously,made the mixed-flow pump slightly less efficient,but with a flatter efficiency curve and relatively wider high efficiency area.By fitting the test results,a functional relation among the BEP of the mixed-flow pump QBEP,the number of deviated blades N,and blade rotation angle deviationαwas established,thus realizing an effective prediction of the BEP of the mixed-flow pump when blade rotation angles have deviations.By model test and numerical simulation,this paper analyzed the effects of different blades with varying rotation angle deviations on the hydraulic performance of a mixed-flow pump.It was found that when some blades had rotation angle deviations,the hydraulic performance curves of the mixed-flow pump would move.With a positive deviation,the curves moved towards the large flow rate;with a negative deviation,the curves moved towards the small flow rate.When some blades had rotation angle deviations,the symmetry and uniformity of the pressure distribution inside the mixed-flow pump flow passage both decreased;the larger the deviation,the greater the decrease.When a single blade had a large rotation angle deviation,a rather clear low pressure area was formed,lowering the cavitation performance.When two adjacent blades changed simultaneously,under the small flow rate condition,adverse pressure gradient and flow separation occurred in the flow field,and a hump appeared in the head curve and the operation stability of the mixed-flow pump dropped significantly.Near the best efficiency point(BEP),the simultaneous change of two alternate blades produced a more significant change of pressure in the flow passage,with an even larger area.Compared to the effect of two adjacent blades,two alternate blades,when changed simultaneously,made the mixed-flow pump slightly less efficient,but with a flatter efficiency curve and relatively wider high efficiency area.By fitting the test results,a functional relation among the BEP of the mixed-flow pump QBEP,the number of deviated blades N,and blade rotation angle deviationαwas established,thus realizing an effective prediction of the BEP of the mixed-flow pump when blade rotation angles have deviations.     

Investigation of performances and flow characteristics of two bi-directional pumps with different airfoil blades

Today, the most commonly used bi-directional airfoil in hydraulic machinery is the S-shaped airfoil (SA). A new bi-directional airfoil, obtained by lowering the bent airfoil camber and thickening the bone line bi-directionally, is proposed. Two bi-directional axial flow pumps, with the SA blades and the arc airfoil (AA) blades, respectively, were designed to verify the applicability of this airfoil. By comparing the hydraulic performances of the two pumps obtained from the experiments, and the cavitation performance and flow field of the two pumps obtained from numerical simulations, it was found that AA blades can improve both the hydraulic and cavitation performances under a low flow rate and near the best efficiency flow point (BEP), whether in forward or reverse operation for the bi-directional axial-flow pump. Furthermore, the hydraulic performance of the AA blade pump declines sharply in a large flow rate compared to that of the SA blade pump. The location and composition of the inhomogeneous flows inside the impellers of the two pumps are similar. However, the SA blades work on fluid, mainly at the front half of the blades, which is a distinctive feature from the AA blades and may be a universal phenomenon in all SA-type blades.     

逆向与正向结合的导叶式混流泵叶片系统反求设计

以某型混流式核主泵的叶轮叶片和导水机构叶片为研究对象,采用在逆向设计的基础上,正向设计校核迭代的技术来探索一条不破坏产品的前提下反求导叶式混流泵的复杂叶片系统的曲面几何数据方法。在不能获取叶片系统的完整曲面数据的情况下,采用叶片数字化设计方法建立沿回转流面上叶型曲线为参数线以便于修改控制的原始叶片系统的近似三维曲面几何模型,并将该模型与其他过流部件组成泵的全流道模型,在0.2~1.2Q_d（设计流量）范围进行泵的全流道流场数值模拟,预测计算出外特性,再与原泵的试验外特性对比,以评估反求的叶片系统流道曲面的准确性。工程应用实践表明,该方法既保证了反求精度又较好地解决了泵的叶片系统反求设计问题。     

离心泵双圆弧圆柱形叶片的几何方程

介绍了一种离心泵双圆弧圆柱形叶片的几何作图方法。推导了这两段圆弧的直角坐标方程和极坐标方程,该方程以离心泵叶片基本参数（内、外半径、叶片包角及进、出口安放角）为变量。通过计算实例验证了该方法的准确性及相关公式的正确性。探讨了两段圆弧半径、圆弧上各点安放角随作图参数α变化的规律。分析表明:在该参数取60°时,本几何作图法所得到的叶片叶轮有较高的水力效率。该方法不需要根据经验多次调节圆弧的半径,也不需要进行数值迭代计算。     

长短叶片半开式离心叶轮内部流动的数值模拟

为了分析分流叶片对于半开式离心叶轮内部流动的影响，对轴向间隙为1.1 mm的4长叶片和4长4短叶片的两种半开式低比转速高速离心叶轮进行了研究.采用S A湍流模型和雷诺时均N-S方程，对叶轮内部的流动进行了三维紊流数值计算和分析；并对离心泵进行了试验研究.数值计算结果表明，分流短叶片可以改善叶轮内部的流动；两个叶轮内部的静压力都由叶片进口到出口逐渐升高，等静压曲线几乎是沿圆周方向的；具有分流叶片的叶轮出口的压力系数较高.实验结果表明，具有分流叶片的叶轮离心泵的扬程和效率较高，说明分流叶片可以提高离心泵的性能.     

冲焊型液力变矩器叶片成形的精密控制

为避免传统叶片制造过程中反复修模、试模问题,本文提出了一种对带有加强筋和折边的YJC265冲焊型液力变矩器泵轮和涡轮的叶片成形进行精密控制的方法。该方法能够预测出叶片制造过程中出现的回弹量,并按计算结果补偿叶片模具型面,得到理想的叶片冲压件;又通过成形回弹计算与模具补偿方法,制造了YJC265液力变矩器样机,且样机性能试验结果超过了设计要求,生产周期和成本远远小于传统方法。本文提出的方法能够保证叶片回弹的精度,指导叶片模具设计,保证模具开发的一次成功率,对变矩器叶片的实际生产具有重要意义。     

面向工业风机叶片划线的2-DOF并联机构运动特性分析

以工业风机叶片加工为应用背景,提出了一种二自由度并联机构,并据此构建一平面划线装置代替传统的叶片手工划线加工工艺.通过分析得出了该装置机构末端执行点（划线头）的位置正逆解、工作空间及奇异位置;按叶片外形轮廓曲线,运用Matlab分析得出了机构划线作业时各输入杆件的运动特性,为实现叶片自动划线加工工艺提供了一种新的思路和保障.     

Numerical Investigation of the Performance of an Axial-Flow Pump with Tandem Blades

The performance characteristics of an axial-flow pump with tandem blades are studied based on the numerical computations. The arrangement of the pump impellers is established through the analysis of velocity triangles. With the commercial computational f