Abstract
A new flow field mathematical model is proposed to describe accurately the flow field structure and calculate the static characteristics of the pilot stage in a deflector jet servo valve (DJSV). The flow field is divided into five regions, a 3D turbulent jet is adopted to describe the free jet region, and a velocity distribution expression of the jet is proposed. The jet entrainment model is put forward in the pressure recovery region to describe the coupling relationship between the pressure in the receiving chamber and the jet flow. The static characteristics, including pressure-flow characteristics, pressure characteristics, and flow characteristics of the pilot stage are obtained. The flow field structure and the static characteristics are verified by finite element analysis (FEA) and experiment, respectively, and the mathematical model results are in good agreement with the experimental and simulation results.
概要
目 的
偏转板伺服阀前置级二维流场模型因忽略了射流在射流盘厚度上的拓展现象, 无法准确地描述偏转板伺服阀前置级流场结构. 为了更加精确地描述流场结构并计算前置级的静态特性, 并有利于优化偏转板伺服阀前置级的结构参数, 本文提出一个符合真实状态的三维流场数学模型.
创新点
1. 在前置级三维流场数学模型中, 将流场分为五个区域, 考虑射流在空间上的三维拓展. 2. 运用三维紊动射流描述自由射流区流场结构, 并提出该区域的射流速度分布表达式. 3. 在压力恢复区提出射流卷吸模型, 并建立起接收腔射流流量和恢复压力的耦合关系.
方 法
1. 通过理论分析, 建立前置级流场各阶段的数学模型 (图2~9), 得到前置级静态特性的理论分析方法 (图11和12); 2. 通过实验研究某型前置级在不同供油压力下的断载压力特性, 验证本文提出的数学模型在计算静态特性时的准确性 (图15); 3. 通过仿真模拟, 分析前置级自由射流区射流截面的速度分布以及接收腔内的射流影响因素, 验证三维射流模型和射流卷吸模型的可行性和有效性 (图17).
结 论
1. 前置级流场内的射流属于三维射流. 本文采用的三维射流可以更加准确地描述流场的结构 (图2). 2. 自由射流区的等速度线接近直槽口形, 可近似用矩形等速度线描述 (图17), 并且接收腔内的射流流量和恢复压力等参数存在耦合关系, 可以用本文提出的卷吸射流模型描述. 3. 在不同供油压力下的前置级无因次断载压力基本一致, 基于三维流场模型得到的前置级静态方法计算结果准确 (图15), 可以为前置级的结构优化提供理论支持.
Similar content being viewed by others
References
Karunanidhi S, Singaperumal M, 2010. Mathematical modelling and experimental characterization of a high dynamic servo valve integrated with piezoelectric actuator. Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering, 224(4): 419–435. https://doi.org/10.1243/09596518JSCE899
Li YS, 2016. Mathematical modelling and characteristics of the pilot valve applied to a jet-pipe/deflector-jet servo-valve. Sensors and Actuators A: Physical, 245:150–159. https://doi.org/10.1016/j.sna.2016.04.048
Liu XQ, Ji H, Min W, et al., 2020. Erosion behavior and influence of solid particles in hydraulic spool valve without notches. Engineering Failure Analysis, 108:104262. https://doi.org/10.1016/j.engfailanal.2019.104262
Liu YS, Dong J, Wu S, et al., 2019. Theoretical research on the dynamic characteristics of electrohydraulic servo valve (EHSV) in deep sea environment. Ocean Engineering, 192:105957. https://doi.org/10.1016/j.oceaneng.2019.04.038
Marsters GF, 1981. Spanwise velocity distributions in jets from rectangular slots. AIAA Journal, 19(2):148–152. https://doi.org/10.2514/3.50935
Saha BK, Li SJ, Lv XB, 2020a. Analysis of pressure characteristics under laminar and turbulent flow states inside the pilot stage of a deflection flapper servo-valve: mathematical modeling with CFD study and experimental validation. Chinese Journal of Aeronautics, 33(3):1107–1118. https://doi.org/10.1016/j.cja.2019.11.016
Saha BK, Peng JH, Li SJ, 2020b. Numerical and experimental investigations of cavitation phenomena inside the pilot stage of the deflector jet servo-valve. IEEE Access, 8: 64238–64249. https://doi.org/10.1109/ACCESS.2020.2984481
Sangiah DK, Plummer AR, Bowen CR, et al., 2013. A novel piezohydraulic aerospace servovalve. Part 1: design and modelling. Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering, 227(4):371–389. https://doi.org/10.1177/0959651813478288
Sforza PM, Steiger MH, Trentacoste N, 1966. Studies on three-dimensional viscous jets. AIAA Journal, 4(5):800–806. https://doi.org/10.2514/33549
Squire HB, Trouncer J, 1944. Round Jets in a General Stream. Aeronautical Research Council, Reports and Memoranda No. 1974, London, UK.
Stefanski F, Minorowicz B, Persson J, et al., 2017. Non-linear control of a hydraulic piezo-valve using a generalised Prandtl—Ishlinskii hysteresis model. Mechanical Systems and Signal Processing, 82:412–431. https://doi.org/10.1016/j.ymssp.2016.05.032
Tamburrano P, Plummer AR, Distaso E, et al., 2018. A review of electro-hydraulic servovalve research and development. International Journal of Fluid Power, 20(1):53–98. https://doi.org/10.13052/ijfp1439-9776.2013
Tamburrano P, Plummer AR, de Palma P, et al., 2020. A novel servovalve pilot stage actuated by a piezo-electric ring bender: a numerical and experimental analysis. Energies, 13(3):671.
Yan H, Ren YK, Yao L, et al., 2019. Analysis of the internal characteristics of a deflector jet servo valve. Chinese Journal of Mechanical Engineering, 32(2):31. https://doi.org/10.1186/s10033-019-0345-7
Yin YB, Yuan JY, Guo SR, 2017. Numerical study of solid particle erosion in hydraulic spool valves. Wear, 392–393: 174–189. https://doi.org/10.1016/j.wear.2017.09.021
Yin YB, Li SL, Zhang XW, et al., 2019. Steady-state flow force calculation of the first stage in a deflector jet servo valve. IEEE 8th International Conference on Fluid Power and Mechatronics, p.452–458. https://doi.org/10.1109/FPM45753.2019.9035735
Zheng FX, Li S, Ding C, et al., 2021. Theoretical and experimental research on the cartridge two-dimensional (2D) electro-hydraulic servo valve. Advances in Mechanical Engineering, 13(2):168781402199653. https://doi.org/10.1177/1687814021996532
Zhu MZ, Zhao SD, Dong P, et al., 2018. Design and analysis of a novel double-servo direct drive rotary valve with high frequency. Journal of Mechanical Science and Technology, 32(9):4313–4323. https://doi.org/10.1007/s12206-018-0829-x
Acknowledgments
This work is supported by the National Natural Science Foundation of China (Nos. 51775383 and 52175059).
Author information
Authors and Affiliations
Contributions
Jia-yang YUAN and Sheng-rong GUO designed the research. Shuang-lu LI processed the corresponding data and wrote the first draft of the manuscript. Yao-bao YIN helped to organize the manuscript and revised and edited the final version.
Corresponding author
Ethics declarations
Shuang-lu LI, Yao-bao YIN, Jia-yang YUAN, and Sheng-rong GUO declare that they have no conflict of interest.
Rights and permissions
About this article
Cite this article
Li, Sl., Yin, Yb., Yuan, Jy. et al. Three-dimensional flow field mathematical model inside the pilot stage of the deflector jet servo valve. J. Zhejiang Univ. Sci. A 23, 795–806 (2022). https://doi.org/10.1631/jzus.A2200030
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1631/jzus.A2200030
Key words
- Deflector jet servo valve (DJSV)
- Pilot stage
- Three-dimensional jets
- Jets entrainment
- Static characteristics
- Mathematical model