Wide Temperature Range Experimental Study into the Fluid Mechanics of Hydraulic Orifices

doi:10.3901/JME.2020.24.190

Abstract

Abstract: A novel experimental equipment capable of testing the fluid mechanics of hydraulic orifices or gaps under low or high temperature conditions is developed. By using the equipment, experiments on discharge characteristics of hydraulic orifices with different geometric parameters are conducted in a wide temperature range of -50-80℃. The effects of the common anti-wear hydraulic oil HM46 and the anti-frozen shock absorber oil TITAN SAF 5045 with different temperatures on the flow-pressure characteristics and its exponent, discharge coefficient of the orifices are then investigated. The research results show that at low temperatures, discharge coefficients of the orifices will drop linearly due to viscosity increasing and fluidity decreasing of the fluids, and in a macro sense, when with HM46 the fluidity is worse and the discharge coefficient drop is obviously greater than that when with TITAN SAF 5045, the discharge coefficient drop of the thick-walled orifice is obviously greater than that of the sharp-edged orifice. The obtained new experimental equipment, test data processing approach and concrete theoretical formulae in this study have brought a new experimental platform and the basic theory for studying and/or optimizing the dynamic performance of modern hydraulic exponents in a wide temperature range.

Key words: hydraulic orifice, fluid mechanics experiment, discharge coefficient, Reynolds number, oil temperature

CLC Number:

TH137

WANG Wenlin, FAN Youquan, DAI Moujun, CHEN Xiang, KONG Xin, WU Yongming. Wide Temperature Range Experimental Study into the Fluid Mechanics of Hydraulic Orifices[J]. Journal of Mechanical Engineering, 2020, 56(24): 190-197.

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