The existing computational models for disengaged wet clutches are deduced based on the single-phase flow theory. However, the complex gas-liquid two-phase flow is formed due to aeration at high rotational speeds. The objective of this study is to use a two-phase flow model to demonstrate the aeration process at different rotational speeds not only of the friction plate but also of the separator plate. A nongrooved, steady-state, two-phase flow computational fluid dynamics model is built using FLUENT, and it is validated by experimental data. The results reveal that air enters the clearance at a critical rotational speed, which causes the drag torque to sharply decrease. The aeration mode and flow pattern are obtained via simulations. The rotational speed of the separator plate has a significant effect on the aeration, including the speed magnitude and direction.

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