# 某潜没式液货泵密封口环磨损量的确定Determination of the Sealing Ring Clearance Wear Amount of a Submerged Cargo Pump

• 全文下载: PDF(1534KB)    PP.167-174   DOI: 10.12677/MET.2019.83021
• 下载量: 52  浏览量: 101   科研立项经费支持

In order to analyze the influence of the sealing ring clearance of a submerged cargo pump on the pump performance, the main flow channel model and five different clearance flow channel models were established and the steady simulation analysis was carried out respectively. The results show that as the sealing ring clearance increases linearly, the pump head and efficiency decrease linearly, which shows that the performance curve moves down as a whole; the static pressure of fluid in the clearance decreases sharply and then increases and then decreases linearly, the velocity of fluid in the clearance first rises and then decreases linearly, the smaller the clearance, the larger the gradient of the pressure drop and the lower the fluid velocity, then the better the sealing effect. Ensuring the sealing effect in engineering applications, the sealing ring should been replaced when the wear amount exceeds 0.2 mm.

1. 引言

2. 计算模型与边界条件

2.1. 间隙模型

Figure 1. Pump head structure of submerged cargo pump

Figure 2. Water body simulation model

2.2. 对比方案

Figure 3. Definition of clearance and eccentricity of sealing ring

Table 1. Contrast table of research programs

2.3. 边界条件

3. 计算结果与分析

3.1. 试验验证

Figure 4. Comparisons between calculated and experimental values

3.2. 外特性分析

(a) 扬程曲线 (b) 效率曲线

Figure 5. External characteristic curves of different research schemes

3.3. 间隙泄露量分析

Table 2. Leakage of upper and lower sealing ring clearance

(单位：kg/s)

3.4. 受力分析

Table 3. Force of pump impeller

(单位：N)

4. 内部流动分析

4.1. 整体静压分布

(a) δ = 0.3 mm (b) δ = 0.5 mm (c) δ = 0.7 mm

Figure 6. Cloud map of static pressure distribution in pump

4.2. 间隙内静压和速度分布

(a) δ = 0.3 mm (b) δ = 0.5 mm(c) δ = 0.7 mm

Figure 7. Cloud map of static pressure and velocity distribution

(a) 静压随间隙长度变化曲线 (b) 速度随间隙长度变化曲线

Figure 8. Performance curve of test pump

5. 结论

1) 随着密封口环间隙线性增大，泵的扬程、效率线性下降，表现为性能曲线整体下移；密封口环的偏心只对泵的径向受力情况有影响，偏心越大，径向力会显著上升，对泵的运行产生不利影响。

2) 间隙内流体运动存在规律性，静压先陡降后增大然后线性减小，流速先上升后线性减小，间隙越小时压降的梯度越大，间隙内的流速也越低，“密封”效果越好。工程上从保证“密封”效果的角度考虑，口环磨损量超过0.2 mm时就应更换密封口环。

3) 文中从密封口环磨损后间隙增大对泵性能的影响这一角度来确定磨损量，实际泵在运行过程中，密封口环间隙增大还会引起泵的振动和噪音增加，此规律有待试验研究来揭示。

 [1] Spence, R. and Amaral-Teixeira, J. (2009) A CFD Parametric Study of Geometrical Variations on the Pressure Pulsations and Per-formance Characteristics of a Centrifugal Pump. Computers & Fluids, 38, 1243-1257. https://doi.org/10.1016/j.compfluid.2008.11.013 [2] 施卫东, 张磊, 陈斌, 等. 离心泵间隙对压力脉动和径向力的影响[J]. 排灌机械工程学报, 2012, 30(3): 260-264. [3] 关醒凡. 现代泵理论与设计[M]. 北京: 中国宇航出版社, 2011. [4] Ayad, A.F., Abdalla, H.M. and Aly, E.A. (2015) Effect of Semi-Open Impeller Side Clearance on the Centrifugal Pump Performance Using CFD. Aerospace Science & Technology, 47, 247-255. https://doi.org/10.1016/j.ast.2015.09.033 [5] 李文广, 费振桃, 蔡永雄. 离心油泵叶轮口环间隙对性能的影响[J]. 水泵技术, 2004(5): 7-13. [6] 陈鱼, 费振桃, 蔡永雄, 等. 输送清水时口环间隙对离心泵性能的影响[J]. 流体机械, 2006, 34(1): 1-5. [7] Lomakin, A.A. (1962) Calculation of Critical Speed and Securing of Dynamic Stability of Hydraulic High-Pressure Pumps with Reference to the Forces Arising in the Gap Seals. Energy of Machinery, 14, 1158-1170. [8] 刘刚, 付强, 朱荣生, 等. 超临界锅炉给水泵级间密封间隙流动特性[J]. 排灌机械工程学报, 2018, 36(5): 391-396, 432. [9] 李琪飞, 刘在伦, 李仁年, 等. 加大叶轮后密封环平衡轴向力的理论分析[J]. 排灌机械, 2004, 22(4): 1-2, 13. [10] 刘在伦, 李振华, 吴佼, 等. 叶轮后密封环直径加大量对轴向力特性的影响[J]. 排灌机械工程学报, 2013, 31(8): 662-666. [11] 王福军. 计算流体动力学分析——CFD软件原理与应用[M]. 北京: 清华大学出版社, 2004.