Numerical Analysis of Effect of Liquid-gas Two-phase Flow on the Drag Torque Characteristics of Wet Clutch

doi:10.3969/j.issn.1000-1093.2020.05.003

Abstract

Abstract: For the purpose of reducing the torque caused by oil shear in disengaged clutch discs，a fluid dynamic simulation about the flow field inside two discs is made in considering the influence of oil-gas mixing process. A 3D CFD simulation model including the information about radial groove is built by STAR-CCM+, which calculates the steady state based on Euler two-phase model and k-ε two-layer turbulence model. The calculated results are used to investigate the effects of the flow rate and relative rotating speed on drag torque, which agree with the experimental results with average error of 7.54%. The correlation between oil-gas distribution and drag torque characteristics is observed by changing the structure of groove angle. The research results show that the drag torquel increases with the flow rate. The maximum torque is 4.63 N·m when the flow rate is 7 L/min, and the values of drag torque are reduced by about 20.95% and 33.69%, respectively, when the flow rate is reduced from 7 L/min to 5 L/min and 3 L/min. The groove angle can reduce the drag torque, and the negative groove angle has a better effect in reducing the drag torque. In the single-phase flow velocity zone, the bigger the positive groove angle is, the better the oil liquidity is, and the bigger the drag torque is. In the two-phase flow velocity zone, the continuity of the oil flow is worse, the proportion of oil is smaller and the the drag torque is smaller with increase in groove angle. Key

Key words: wetclutch, fluiddynamicsimulation, dragtorque, grooveangle

CLC Number:

TJ810.3⁺21

CHENG Xiao， ZHU Maotao, TIAN Naili. Numerical Analysis of Effect of Liquid-gas Two-phase Flow on the Drag Torque Characteristics of Wet Clutch[J]. Acta Armamentarii, 2020, 41(5): 850-857.

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第41卷第5期2020 年5月
兵工学报ACTA ARMAMENTARII
Vol.41No.5May2020

[1]	ZHANG Lin, WEI Chao, HU Jibin, HU Qi. Rub-impact Characteristics and Drag Torque at High Circumferential Velocities in No-load Multi-plate Wet Clutch for Vehicles [J]. Acta Armamentarii, 2020, 41(7): 1270-1279.
[2]	SHI Lu-qi， MA Biao， LI He-yan， WU Jun-feng， LI Hui-zhu， YAN Xu， CHANG Fu-xiang. Modeling and Experimental Validation of Drag Torque of Wet Multi-disk Clutch with Spline Connected Restriction in Full SpeedRange [J]. Acta Armamentarii, 2018, 39(9): 1665-1674.
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[4]	ZHAO Er-hui, MA Biao, LI He-yan, DU Qiu, LI Hui-zhu, MA Cheng-nan. Influence of Rotating Speed on Local Lubrication and Friction Characteristics of Wet Clutch [J]. Acta Armamentarii, 2017, 38(4): 625-633.