Shock Absorbers Damping Characteristics by Lightweight Drop Hammer Test for Naval Machines
Andrzej Grządziela1, Marcin Kluczyk1
1Mechanical-Electrical Department, Polish Naval Academy of the Heroes of Westerplatte, 81-103 Gdynia, Poland.
Materials (Basel, Switzerland)
|February 10, 2021
Summary
Naval ship shock absorbers made from rubber and elastomers were tested for underwater explosion (UNDEX) resistance. Materials were evaluated for energy absorption, temperature range, and vibration damping, ensuring reliable performance under harsh conditions.
Area of Science:
- Naval Engineering
- Materials Science
- Mechanical Engineering
Background:
- Naval ship foundations require stringent shock absorption due to Underwater Explosions (UNDEX).
- Military standardization mandates robust designs for naval vessels, unlike merchant ships.
- Diverse materials are employed for shock absorbers to mitigate UNDEX impacts.
Purpose of the Study:
- To evaluate rubber and elastomer shock absorbers for naval applications.
- To determine energy absorption capabilities under shock impacts.
- To assess material suitability for operational temperatures (0-70°C), fluid resistance, and vibration damping (≥40% harmonic energy).
Main Methods:
- Tensile testing to determine static and dynamic stiffness.
- Drop hammer tests to characterize damping coefficients for high-speed impacts.
- Shock Response Spectrum (SRS) analysis for high-speed wave interactions.
Main Results:
- Characterization of stiffness coefficients in linear and nonlinear ranges.
- Evaluation of damping characteristics for high-speed impacts.
- Assessment of material properties for energy absorption and repeatability under multiple impacts.
Conclusions:
- Tested rubber and elastomer materials demonstrate potential for naval shock absorption.
- The study provides mechanical property data crucial for designing UNDEX-resistant naval foundations.
- Material selection and design considerations for shock absorbers were informed by experimental results.
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