A Stiffness Reduction Method for efficient absorption of waves at boundaries for use in commercial Finite Element...

Area of Science:

• Computational Mechanics
• Solid Mechanics
• Wave Propagation

Background:

• Commercial Finite Element (FE) packages are widely used for elastic wave propagation modeling.
• Accurate modeling in unbound elastic media is challenging due to the need to eliminate boundary reflections.
• Existing methods like Absorbing Layers by Increasing Damping (ALID) require large spatial domains.

Purpose of the Study:

• To develop a novel method for modeling elastic wave propagation in unbound media.
• To reduce the spatial domain required for accurate wave modeling.
• To improve upon the efficiency and effectiveness of existing absorbing layer techniques.

Main Methods:

• A Stiffness Reduction Method (SRM) was developed, altering damping and stiffness matrices to induce wave decay.
• The SRM operates within a significantly reduced spatial domain compared to ALID.
• Absorbing region variables are expressed using known model constants for broad applicability.

Main Results:

• The Stiffness Reduction Method (SRM) demonstrated superior performance compared to the Absorbing Layers by Increasing Damping (ALID) technique.
• Numerical and analytical results confirmed the effectiveness of the SRM.
• The SRM allows for modeling within a substantially reduced spatial domain.

Conclusions:

• The Stiffness Reduction Method (SRM) offers a more efficient and effective approach to modeling elastic wave propagation in unbound media.
• SRM provides a valuable alternative for commercial Finite Element software, enhancing capability without source code modification.
• This method significantly reduces computational domain size while maintaining high accuracy.