Effects of blade thickness on hydraulic performance and structural dynamic characteristics of high-power coolant pump at overload condition

Abstract

As an indispensable equipment in thermal power plants, the high-power coolant pump is necessary for high hydraulic performance with good structural safety for transferring of heat produced by fuels. However, the design of blade thickness for coolant pump especially at the off-design condition is still empirical and arbitrary. In the present work, the hydraulic performance, internal flow pattern, and structural response arising from the variations of blade thickness in coolant pump have been investigated using computational fluid dynamics and fluid–structure interaction methods. The numerical results have been verified by experimental performance and found to be good. To improve the accuracy of head calculation at the overload condition, a modified equation is proposed with the help of multi-island genetic algorithm and the average deviation is reduced from 58.50 to 1.59%. With the blade thickening process, the hydraulic performance is gradually deteriorated especially at the overload condition, and the flow behavior is changed with the proportion of high velocity near the pressure surface enlarging, the proportion of low velocity near the suction surface decreasing, and the pressure fluctuation intensity rising. Besides, increasing the blade thickness beyond 23.0 mm, the stress reduction is not effective. However, it helps to increase the natural frequency for suppressing the resonance. Finally, considering the optimal hydraulic and structural performances, the blade thickness is optimized to 23.0 mm.

Keywords

Coolant pump blade thickness hydraulic performance structural response overload condition fluid–structure interaction

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References

Gülich

. Centrifugal pumps, Springer: Berlin, 2008.

Malyushenko

Aspidov

Andryushchenko

. Selection of optimal thickness of centrifugal-pump impeller vanes. Chem Petrol Eng 1977; 13: 987–989.

Luo

Zhang

Peng

et al.

Impeller inlet geometry effect on performance improvement for centrifugal pumps. J Mech Sci Technol 2008; 22: 1971–1976.

Goel

Dorney

Haftka

et al.

Improving the hydrodynamic performance of diffuser vanes via shape optimization. Comput Fluids 2008; 37: 705–723.

Kim

Ahn

Kim

. High-efficiency design of a mixed-flow pump. Sci China Technol Sci 2010; 53: 24–27.

Kim

. Analysis and optimization of a vaned diffuser in a mixed flow pump to improve hydrodynamic performance. J Fluids Eng 2012; 134: 071104–071104.

Kim

Lee

Kim

et al.

Design techniques to improve the performance of a centrifugal pump using CFD. J Mech Sci Technol 2015; 29: 215–225.

Skrzypacz

Bieganowski

. The influence of micro grooves on the parameters of the centrifugal pump impeller. Int J Mech Sci 2017.

Nishi

Fukutomi

. Effect of blade outlet angle on unsteady hydrodynamic force of closed-type centrifugal pump with single blade. Int J Rotating Mach 2014; 2014: 1–16.

10.

Tao

Yuan

Liu

et al.

Influence of blade thickness on transient flow characteristics of centrifugal slurry pump with semi-open impeller. Chin J Mech Eng 2016; 29: 1209–1217.

11.

Tao

Yuan

Liu

et al.

The influence of the blade thickness on the pressure pulsations in a ceramic centrifugal slurry pump with annular volute. Proc IMechE, Part A: J Power and Energy 2017; 231: 415–431.

12.

Tan

Zhu

Cao

et al.

Influence of blade wrap angle on centrifugal pump performance by numerical and experimental study. Chin J Mech Eng 2014; 27: 171–177.

13.

Tan

et al.

Role of blade rotational angle on energy performance and pressure fluctuation of a mixed-flow pump. Proc IMechE, Part A: J Power and Energy 2017; 231: 227–238.

14.

Wang

Tan

Zhu

et al.

Numerical investigation of influence of inlet guide vanes on unsteady flow in a centrifugal pump. Proc IMechE, Part C: J Mechanical Engineering Science 2015; 229: 3405–3416.

15.

Wang

Huang

Liu

et al.

Effect of inclined trailing edge of blade on exterior radiation noise of marine centrifugal pump. J Drainage Irrigation Mach Eng 2015; 33: 104–110.

16.

Huang

Yuan

Zhang

et al.

Effects of blade wrap angle on performance of high specific speed centrifugal pump. J Drainage Irrigation Mach Eng 2016; 34: 742–747.

17.

Zhou

Yang

Shi

et al.

Influence of outlet edge position of diffuser vane on performance of deep-well centrifugal pump. J Drainage Irrigation Mach Eng 2016; 34: 1028–1034.

18.

Yuan

Pei

et al.

Effects of the outlet width of pump impeller on pressure fluctuation intensity in volute. J Harbin Eng Univ 2017; 38: 1–8.

19.

Benra

. Numerical and experimental investigation on the flow induced oscillations of a single-blade pump impeller. J Fluids Eng 2006; 128: 783–793.

20.

Pei

Dohmen

Yuan

et al.

Investigation of unsteady flow-induced impeller oscillations of a single-blade pump under off-design conditions. J Fluids Struct 2012; 35: 89–104.

21.

Pei

Benra

Dohmen

. Application of different strategies of partitioned fluid–structure interaction simulation for a single-blade pump impeller. Proc IMechE, Part E: J Process Mechanical Engineering 2012; 226: 297–308.

22.

Schneider A, Will BC and Böhle M. Numerical evaluation of deformation and stress in impellers of multistage pumps by means of fluid structure interaction. In: ASME 2013 fluids engineering division summer meeting. Incline Village, Nevada, USA, July 711, 2013. Paper No. FEDSM2013-16337, USA: ASME, pp. V01BT10A020.

23.

Zhou

Yuan

et al.

Investigation of dynamic stress of rotor in residual heat removal pumps based on fluid–structure interaction. Adv Mech Eng 2016; 8: 1–12.

24.

Egusquiza E, Valero C, Liang Q, et al. Fluid added mass effect in the modal response of a pump-turbine impeller. In: ASME 2009 international design engineering technical conferences and computers and information in engineering conference. San Diego, California, USA, August 30September 2, 2009. USA: ASME; pp. 715–724.

25.

Liu

Dou

et al.

Numerical prediction and similarity study of pressure fluctuation in a prototype Kaplan turbine and the model turbine. Comput Fluids 2012; 56: 128–142.

26.

Audebert S, Coulon A, Andrianoely MA, et al. Experimental variability on modal characteristics of an in-situ pump. In: Model validation and uncertainty quantification. Vol. 3. Cham: Springer International Publishing, 2015, pp. 163–169.

27.

Tong

Zhang

et al.

Dynamic behavior and sound transmission analysis of a fluid–structure coupled system using the direct-BEM/FEM. J Sound Vib 2007; 299: 645–655.

28.

Maki

Lee

Troesch

et al.

Hydroelastic impact of a wedge-shaped body. Ocean Eng 2011; 38: 621–629.

29.

Piro

Maki

. Hydroelastic analysis of bodies that enter and exit water. J Fluids Struct 2013; 37: 134–150.

30.

Menter

. Two-equation eddy-viscosity turbulence models for engineering applications. AIAA J 1994; 32: 1598–1605.

31.

Guan

. Modern pump theory and design, China Astronautic: Beijing, 2011.

32.

Tan

Zhu

Cao

et al.

Numerical simulation of unsteady cavitation flow in a centrifugal pump at off-design conditions. Proc IMechE, Part C: J Mechanical Engineering Science 2014; 228: 1994–2006.

33.

Tan

Zhu

Wang

et al.

Numerical study on characteristics of unsteady flow in a centrifugal pump volute at partial load condition. Eng Comput 2015; 32: 1549–1566.