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Updated: Jan 10, 2026

Parametric Optimization Design Method for Friction Plates of Hydro-Viscous Clutches
Published on: July 22, 2025
A hybrid analytical and data driven framework for optimizing radially grooved wet clutch geometry.
Mohammad Sadafi1, Amir F Najafi2, Alireza Jalali1
1School of Mechanical Engineering, College of Engineering, University of Tehran, P.O. Box 11365/4563, Tehran, Iran.
Optimizing radially grooved wet clutches significantly minimizes drag torque, achieving over 70% reduction. Adjusting disk distance proved most effective, while groove angle had minimal impact.
Area of Science:
- Mechanical Engineering
- Fluid Dynamics
- Tribology
Background:
- Drag torque in wet clutches arises from relative motion of disks within an oil film.
- Minimizing drag torque is crucial for improving efficiency in wet clutch systems.
Purpose of the Study:
- To optimize the geometry of radially grooved wet clutches for drag torque reduction.
- To develop and validate data-driven models for predicting drag torque.
Main Methods:
- An analytical model was employed to generate datasets for single- and multiphase flow conditions.
- Computational Fluid Dynamics (CFD) validated the analytical model's accuracy (max 8% deviation).
- Artificial neural networks and a genetic algorithm were used for optimization.
Main Results:
- Optimized geometries achieved drag torque reductions of at least 70% across four cases.
- Case 3 showed a 97% reduction in peak drag torque (0.92 to 0.022).
- Parametric study revealed disk distance as the most impactful parameter (86% reduction), groove angle the least (2% reduction).
Conclusions:
- Data-driven optimization effectively minimizes drag torque in radially grooved wet clutches.
- Geometric parameters significantly influence drag torque, with disk spacing being a key factor.
- The developed models offer an efficient alternative to computationally expensive numerical simulations.
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