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Parametric Optimization Design Method for Friction Plates of Hydro-Viscous Clutches
Published on: July 22, 2025
Variational scheme towards an optimal lifting drive in fluid adhesion
Eduardo O Dias1, José A Miranda
1Departamento de Física, Universidade Federal de Pernambuco, Recife PE 50670-901, Brazil.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|December 11, 2012
Summary
Minimizing fluid adhesion energy is possible by optimizing the lifting drive. This new method significantly reduces adhesion force peaks for Newtonian and power-law fluids, saving energy.
Area of Science:
- Fluid mechanics
- Rheology
- Surface science
Background:
- Probe-tack tests measure liquid adhesive strength by separating fluid-filled plates.
- Current methods often use high-viscosity fluids and constant lifting velocities, leading to high energy costs.
- Optimizing the lifting strategy for minimal energy expenditure is an open challenge.
Purpose of the Study:
- To determine the optimal time-dependent lifting drive (Lopt(t)) for minimizing adhesion energy.
- To investigate the impact of an optimized lifting drive on adhesion force peaks.
- To validate the proposed method for both Newtonian and power-law fluids.
Main Methods:
- A variational scheme was employed to systematically search for the optimal lifting drive.
- Theoretical analysis was used to derive the conditions for energy minimization.
- Simulations and/or experiments were conducted to verify the findings.
Main Results:
- An optimal lifting drive (Lopt(t)) was identified that minimizes adhesion energy.
- Employing the optimal drive significantly reduces the peak adhesion force.
- The energy-saving benefits and force reduction were confirmed for Newtonian and power-law fluids.
Conclusions:
- Optimized lifting strategies offer a more energy-efficient approach to probe-tack testing.
- This method effectively reduces peak adhesion forces, potentially improving experimental control.
- The findings are applicable to a range of fluid types, including non-Newtonian fluids.
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