Shape-dependent initial pressure effects of fluid inclusions in an elastic solid under plane deformation
Junfeng Lu1, Yu-Hao Zhang2, Ming Dai2
1School of Electrical and Mechanical Engineering, Jinling Institute of Technology, Nanjing, China.
Mathematics and Mechanics of Solids : MMS
|August 6, 2026
Summary
Initial pressure in fluid inclusions significantly impacts the elastic properties of solid composites. This pressure enhances effective moduli, with effects varying based on inclusion shape and complexity.
Area of Science:
- Solid Mechanics
- Materials Science
- Composite Materials
Background:
- Classical linear elasticity fails to account for initial pressure effects in fluid-inclusions.
- The initial pressure within inclusions is crucial for the composite's response to external loads.
Purpose of the Study:
- To investigate the influence of initial internal pressure on the elastic behavior of solid-fluid composites.
- To derive analytical solutions for stress distribution and effective properties considering initial pressure.
Main Methods:
- Utilized a modified boundary condition approach for plane deformation analysis.
- Derived closed-form solutions for incremental stress around arbitrary-shaped inclusions.
- Applied homogenization methods to determine effective composite properties.
Main Results:
- Initial internal pressure consistently enhances the effective elastic moduli of the composite.
- Enhancement effects decrease with increasing sides for polygonal inclusions.
- Enhancement effects increase with inclusion slenderness for rectangular and elliptical inclusions.
Conclusions:
- Initial pressure is a critical parameter in modeling solid-fluid composites.
- Inclusion shape significantly modulates the impact of initial pressure on composite stiffness.
- The findings offer a more accurate prediction of composite behavior under load.
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