Advanced Characterisation of Soft Polymers under Cyclic Loading in Context of Engine Mounts.
Tomáš Gejguš1, Jonas Schröder1, Klara Loos1
1Institute of Mechanics, Bundeswehr University Munich, 85577 Neubiberg, Germany.
Polymers
|February 15, 2022
Summary
This study presents new methods for measuring the viscoelastic behavior of elastomeric components under cyclic loading. These advanced techniques improve the simulation accuracy for virtual prototypes, reducing development time and costs.
Area of Science:
- Materials Science
- Mechanical Engineering
- Polymer Physics
Background:
- Cyclically loaded elastomeric components are critical in industrial applications, particularly in automotive engineering.
- Understanding their viscoelastic behavior in both time and frequency domains is essential for performance and durability.
- Numerical simulations and virtual prototypes are increasingly important for design validation.
Purpose of the Study:
- To experimentally investigate and validate the viscoelastic behavior of elastomeric components under cyclic loading.
- To develop and evaluate new measurement techniques for high-frequency dynamic stiffness and large deformation analysis.
- To improve the simulation accuracy of elastomeric components in virtual prototypes for automotive applications.
Main Methods:
- Development of a new test bench for high-frequency dynamic stiffness measurements up to 3000 Hz.
- Comparison of the new test bench with standard dynamic measurement methods for soft polymers.
- Implementation of a new concept for identifying viscoelastic material parameters under large periodic deformations and energy dissipation.
- Thermal and mechanical validation of the developed concepts on specimen and component levels.
Main Results:
- A significant difference in dynamic stiffness values was observed due to internal resonance, which is missed by conventional methods.
- The new methods accurately capture high-frequency effects relevant to electric vehicles.
- The developed concept effectively represents large deformations and energy dissipation, crucial for internal combustion engine applications.
- Simulations using the developed approaches can accurately predict the behavior of elastomeric engine mounts.
Conclusions:
- The developed experimental and simulation approaches enhance the understanding and prediction of elastomeric component behavior under cyclic loading.
- These advancements are critical for optimizing the performance, acoustic behavior, and durability of components in electric and conventional vehicles.
- The study facilitates reduced prototyping costs and development time through accurate virtual simulations.
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