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Research Papers: Flows in Complex Systems

Effect of Oil Viscosity on Self-Excited Noise Production Inside the Pilot Stage of a Two-Stage Electrohydraulic Servovalve

[+] Author and Article Information
Meng Chen

Department of Fluid Control and Automation,
Harbin Institute of Technology,
Science Park, No. 2,
Yikuang Street Nangang District, Box 3040
Harbin 150001, China;
MCC Huatian Engineering &
Technology Corporation,
No.18, Fuchunjiangdong Street, Jianye District,
Nanjing 210019, China,
e-mail: chenmeng666666@163.com

Nay Zar Aung

Department of Mechatronic Engineering,
Yangon Technological University,
3rd Floor, TRC Builiding,
YTU Campus, Insein Road,
Yangon 11181, Myanmar
e-mail: nay1572@gmail.com

Songjing Li

Department of Fluid Control and Automation,
Harbin Institute of Technology,
Science Park, No. 2,
Yikuang Street Nangang District, Box 3040
Harbin 150001, China
e-mail: lisongjing@hit.edu.cn

Changfang Zou

MCC Huatian Engineering &
Technology Corporation,
No.18, Fuchunjiangdong Street, Jianye District,
Nanjing 210019, China
e-mail: zchf1983@aliyun.com

1Corresponding author.

Contributed by the Fluids Engineering Division of ASME for publication in the JOURNAL OF FLUIDS ENGINEERING. Manuscript received September 7, 2017; final manuscript received June 1, 2018; published online June 29, 2018. Assoc. Editor: Bart van Esch.

J. Fluids Eng 141(1), 011106 (Jun 29, 2018) (15 pages) Paper No: FE-17-1562; doi: 10.1115/1.4040500 History: Received September 07, 2017; Revised June 01, 2018

The occurrence of self-excited noise felt as squealing noise is a critical issue for an electrohydraulic servovalve that is an essential part of the hydraulic servocontrol system. Aiming to highlight the root causes of the self-excited noise, the effect of oil viscosity on the noise production inside a two-stage servovalve is investigated in this paper. The pressure pulsations' characteristics and noise characteristics are studied at three different oil viscosities experimentally by focusing on the flapper-nozzle pilot stage of a two-stage servovalve. The cavitation-induced and vortex-induced pressure pulsations' characteristics at upstream and downstream of the turbulent jet flow path are extracted and analyzed numerically by comparing with the experimental measured pressure pulsations and noise characteristics. The numerical simulations of transient cavitation shedding phenomenon are also validated by the experimental cavitation observations at different oil viscosities. Both numerical simulations and experimental cavitation observations explain that cavitation shedding phenomenon is intensified with the decreasing of oil viscosity. The small-scale vortex propagation with the characteristic of generating, growing, moving, and merging is numerically simulated. Thus, this study reveals that the oil viscosity affects the transient distribution of cavitation and small-scale vortex, which, in turn, enhances the pressure pulsation and noise. The noise characteristics achieve a good agreement with pressure pulsation characteristics showing that the squealing noise appears accompanied by the flow field resonance in the flapper-nozzle. The flow-acoustic resonance and resulting squealing noise possibly occurs when the amplitude of the pressure pulsations near the flapper is large enough inside a two-stage servovalve.

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References

Zhang, K. , Yao, J. , and Jiang, T. , 2014, “ Degradation Assessment and Life Prediction of Electro-Hydraulic Servo Valve Under Erosion Wear,” Eng. Fail. Anal., 36, pp. 284–300. [CrossRef]
Li, S. , and Song, Y. , 2007, “ Dynamic Response of a Hydraulic Servo-Valve Torque Motor With Magnetic Fluids,” Mechatronics, 17(8), pp. 442–447. [CrossRef]
Li, S. , and Bao, W. , 2008, “ Influence of Magnetic Fluids on the Dynamic Characteristics of a Hydraulic Servo-Valve Torque Motor,” Mech. Syst. Signal Process., 22(4), pp. 1008–1015. [CrossRef]
Weber, S. T. , Porteiro, J. L. , Rahman, M. M. , Pennington, R. E. , and Musallam, A. E. , 1998, “ Self-Sustaining Flow Oscillations in Counterbalance Valves,” Bath Workshop on Power Transmission and Motion Control, pp. 207–217.
Li, S. , Peng, J. , Zhang, S. , and Mchenya, J. M. , 2012, “ Depression of Self-Excited Pressure Oscillations and Noise in the Pilot Stage of a Hydraulic Jet-Pipe Servo-Valve Using Magnetic Fluids,” Adv. Mater. Res., 378, pp. 632–635. [CrossRef]
Peng, J. , Li, S. , and Fan, Y. , 2014, “ Modeling and Parameter Identification of the Vibration Characteristics of Armature Assembly in a Torque Motor of Hydraulic Servo Valves Under Electromagnetic Excitations,” Adv. Mech. Eng., 6, p. 247384. [CrossRef]
Watton, J. , 1987, “ The Effect of Drain Orifice Damping on the Performance Characteristics of a Servovalve Flapper/Nozzle Stage,” ASME J. Dyn. Syst., Meas., Control, 109(1), pp. 19–23. [CrossRef]
Porteiro, J. L. , Weber, S. T. , and Rahman, M. M. , 1997, “ An Experimental Study of Flow Induced Noise in Counterbalance Valves,” International Symposium on Fluid-Structure Interactions, Aeroelasticity, Flow-Induced Vibration and Noise, Dallas, TX, pp. 557–562.
Martin, C. S. , Medlarz, H. , Wiggert, D. C. , and Brennen, C. , 1981, “ Cavitation Inception in Spool Valves,” ASME J. Fluids Eng., 103(4), pp. 564–575. [CrossRef]
Zou, J. , Fu, X. , Du, X. W. , Ruan, X. D. , Ji, H. , Ryu, S. , and Ochiai, M. , 2008, “ Cavitation in a Non-Circular Opening Spool Valve With U-Grooves,” Proc. Inst. Mech. Eng., Part A, 222(4), pp. 413–420. [CrossRef]
Lu, L. , Zou, J. , and Fu, X. , 2012, “ The Acoustics of Cavitation in Spool Valve With U-Notches,” Proc. Inst. Mech. Eng. Part G, 226(5), pp. 540–549. [CrossRef]
Fu, X. , Lu, L. , Ruan, X. D. , Zou, J. , and Du, X. W. , 2008, “ Noise Properties in Spool Valves With Cavitating Flow,” International Conference on Intelligent Robotics and Applications, pp. 1241–1249.
Yi, D. Y. , Lu, L. , Zou, J. , and Fu, X. , 2016, “ Squeal Noise in Hydraulic Poppet Valves,” J. Zhejiang Univ. Sci. A, 17(4), pp. 317–324. [CrossRef]
Xu, B. , Su, Q. , Zhang, J. , and Lu, Z. , 2017, “ A Dead-Band Model and Its Online Detection for the Pilot Stage of a Two-Stage Directional Flow Control Valve,” Proc. Inst. Mech. Eng. Part C, 230(4), pp. 639–654. [CrossRef]
Xu, B. , Su, Q. , Zhang, J. , and Lu, Z. , 2017, “ Analysis and Compensation for the Cascade Dead-Zones in the Proportional Control Valve,” ISA Trans., 66, pp. 393–403. [CrossRef] [PubMed]
Le, Q. , Franc, J. P. , and Michel, J. M. , 1993, “ Partial Cavities: Pressure Pulse Distribution Around Cavity Closure,” ASME J. Fluids Eng., 115(2), pp. 249–254. [CrossRef]
Stanley, C. , Barber, T. , and Rosengarten, G. , 2014, “ Re-Entrant Jet Mechanism for Periodic Cavitation Shedding in a Cylindrical Orifice,” Int. J. Heat Fluid Flow, 50, pp. 169–176. [CrossRef]
Dai, S. , Younis, B. A. , and Sun, L. , 2014, “ Large-Eddy Simulations of Cavitation in a Square Surface Cavity,” Appl. Math. Model., 38(23), pp. 5665–5683. [CrossRef]
Leroux, J. B. , Astolfi, J. A. , and Billard, J. Y. , 2004, “ An Experimental Study of Unsteady Partial Cavitation,” ASME J. Fluids Eng., 126(1), pp. 94–101. [CrossRef]
Watanabe, S. , Tsujimoto, Y. , and Furukawa, A. , 2001, “ Theoretical Analysis of Transitional and Partial Cavity Instabilities,” ASME J. Fluids Eng., 123(3), pp. 692–697. [CrossRef]
Chong, D. , Zhao, Q. , Yuan, F. , Cong, Y. , Chen, W. , and Yan, J. , 2015, “ Experimental and Theoretical Study on the Second Dominant Frequency in Submerged Steam Jet Condensation,” Exp. Therm. Fluid Sci., 68, pp. 744–758. [CrossRef]
Chen, W. , Zhao, Q. , Wang, Y. , Sen, P. K. , Chong, D. , and Yan, J. , 2016, “ Characteristic of Pressure Oscillation Caused by Turbulent Vortexes and Affected Region of Pressure Oscillation,” Exp. Therm. Fluid Sci., 76, pp. 24–33. [CrossRef]
Zhu, J. , Chen, H. , and Chen, X. , 2013, “ Large Eddy Simulation of Vortex Shedding and Pressure Fluctuation in Aerostatic Bearings,” J. Fluids Struct., 40, pp. 42–51. [CrossRef]
Li, S. , Aung, N. Z. , Zhang, S. , Cao, J. , and Xue, X. , 2013, “ Experimental and Numerical Investigation of Cavitation Phenomenon in Flapper-Nozzle Pilot Stage of an Electrohydraulic Servo-Valve,” Comput. Fluids, 88, pp. 590–598. [CrossRef]
Aung, N. Z. , and Li, S. , 2014, “ A Numerical Study of Cavitation Phenomenon in a Flapper-Nozzle Pilot Stage of an Electrohydraulic Servo-Valve With an Innovative Flapper Shape,” Energy Convers. Manage., 77, pp. 31–39. [CrossRef]
Yang, Q. , Aung, N. Z. , and Li, S. , 2015, “ Confirmation on the Effectiveness of Rectangle-Shaped Flapper in Reducing Cavitation in Flapper-Nozzle Pilot Stage,” Energy Convers. Manage., 98, pp. 184–198. [CrossRef]
Zhang, S. , and Li, S. , 2015, “ Cavity Shedding Dynamics in a Flapper–Nozzle Pilot Stage of an Electro-Hydraulic Servo-Valve: Experiments and Numerical Study,” Energy Convers. Manage., 100, pp. 370–379. [CrossRef]
Wang, G. , and Ostoja-Starzewski, M. , 2007, “ Large Eddy Simulation of a Sheet/Cloud Cavitation on a NACA0015 Hydrofoil,” Appl. Math. Model., 31(3), pp. 417–447. [CrossRef]
Dittakavi, N. , Chunekar, A. , and Frankel, S. , 2010, “ Large Eddy Simulation of Turbulent-Cavitation Interactions in a Venturi Nozzle,” ASME J. Fluids Eng., 132(12), p. 121301. [CrossRef]
ANSYS/FLUENT, 2011, Users Guide, 13th ed., ANSYS, Inc., Canonsburg, PA.
Hutli, E. , and Nedeljkovic, M. , 2008, “ Frequency in Shedding/Discharging Cavitation Clouds Determined by Visualization of a Submerged Cavitating Jet,” ASME J. Fluids Eng., 130(2), p. 021304. [CrossRef]
Nishimura, S. , Takakuwa, O. , and Soyama, H. , 2012, “ Similarity Law on Shedding Frequency of Cavitation Cloud Induced by a Cavitating Jet,” J. Fluid Sci. Technol., 7(3), pp. 405–420. [CrossRef]

Figures

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Fig. 1

A typical two-stage servovalve

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Fig. 2

Close-up views of the flapper-nozzle pilot stage: (a) flow field in the section A-A and (b) flow field in the section B-B

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Fig. 3

Computational domain: (a) boundary conditions and (b) geometry dimensions in the section A-A (mm)

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Fig. 4

Meshed model of the flapper-nozzle pilot stage

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Fig. 5

Pressure along line L of different grid systems

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Fig. 6

Schematic diagram of experimental setup: 1—hydraulic power supply, 2—pressure gauges, 3—servo-valve, 4—actuator, 5—piezoelectric microphone, 6—piezoelectric pressure sensor, 7—feedback sensor, 8—data-acquisition board, 9—computer, 10—throttle valves, 11—flapper-nozzle pilot stage, 12—camera, 13—light source, and 14—flow meter

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Fig. 7

Pictures of the experimental setup: (a) tested servo-valve and (b) cavitation observation system

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Fig. 8

Volume vapor fraction at three oil viscosities

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Fig. 9

Comparison of simulations and experimental cavitation observations at the oil viscosity of 0.015N·s/m2 (t0 = 5 s, △t = 5 × 10−5 s)

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Fig. 10

Comparison of simulations and experimental cavitation observations at the oil viscosity of 0.0085N·s/m2 (t0 = 5 s, △t = 5 × 10−5 s)

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Fig. 11

Comparison of simulations and experimental cavitation observations at the oil viscosity of 0.006N·s/m2 (t0 = 5 s, △t = 5 × 10−5 s)

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Fig. 12

Comparison of numerical velocity streamline at the oil viscosity of 0.0085 N·s/m2 and the outlet pressure of 0.2 MPa (t0 = 5 s, △t = 5 × 10−5 s)

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Fig. 13

Numerical pressure pulsations at location A: (a) in time domain and (b) in frequency domain

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Fig. 14

Numerical pressure pulsations at location B: (a) in time domain and (b) in frequency domain

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Fig. 15

Experimental pressure pulsations characteristics: (a) in time domain and (b) in frequency domain

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Fig. 16

Noise characteristics: (a) in time domain and (b) in frequency domain

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