Flow measurement for the pre-stage of jet pipe servo valve using 2D -PIV technique

ABSTRACT

In order to investigate the internal flow field characteristic for the pre-stage of jet pipe servo valve, a large-scale low-speed flow field visualisation experimental platform was developed. The internal flow field for the pre-stage of jet pipe servo valve was measured directly by particle image velocimetry (PIV), and its internal flow characteristics were obtained. The experimental results show that four vortices exist in the upper area and the lower area of the lower chamber of pre-stage. The upper chamber has two wide range of vortex in the pre-stage of jet pipe servo valve, and the vortex scale increases with the increase of flow rate. With the flow rate increases, the vortex in the upper area will disappear. The scale of the vortex in the lower area gradually increases with the increase of the flow rate, and the position gradually moves upwards. Under different deflection angles of jet pipe, the main characteristics of the vortex pre-stage are roughly the same, but the size and core of the vortex are different. The results provide a reference for the structural optimisation of the jet pipe servo valve.

KEYWORDS:

• Jet pipe servo valve
• particle image velocimetry(PIV)
• flow field
• vortex

Nomenclature

µ	=	Dynamic viscosity [Pa•s]
L	=	Length [mm]
Re	=	Reynolds number
Δt	=	Time between pulses[μs]
v	=	Velocity [m/s]
q	=	Flow rate [L/min]
ρ	=	Fluid density [kg/m3]

Acknowledgements

The authors would like to give their acknowledgement to the National Natural Science Foundation of China (No. 51705446) and Open Foundation of the State Key Laboratory of Fluid Power and Mechatronic Systems (No. GZKF-201716) for financial support.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (CN) [No. 51705446] and Open Foundation of the State Key Laboratory of Fluid Power and Mechatronic Systems [No. GZKF-201716].

Notes on contributors

Jianjun Hu

Jianjun Hu received his Ph.D. degree in Yanshan University, China in 2015, and now he is an associate professor in Yanshan University. His research area involves fluid power transmission and control.

Zehe Yang

Zehe Yang is a postgraduate students in the College of Mechanical Engineering at Yanshan University, China. His main research interests include visualization analysis of hydraulic components flow field.