Multiscale Modeling and Experimental Assessment of Damping in Unidirectional Fiber Reinforced Composites
Topic(s) : Material and Structural Behavior - Simulation & Testing
Co-authors :
Edgar Arturo GOMEZ MEISEL (DENMARK), Pauline BUTAUD (FRANCE), Morvan OUISSE (FRANCE), Vincent PLACET (FRANCE)Abstract :
With a growing need for materials sourced from renewable origins, bio-based composites are becoming increasingly popular. Natural fibers, serving as an alternative to widely used glass and carbon fibers, are gaining attention due to their sustainability, renewability, environmental friendliness, lightweight nature, and cost-effectiveness [1]. The distinctive focus lies on the unique properties of these natural fibers, highlighting their contribution to the overall composite's profile. Additionally, bio-based composites exhibit superior damping properties compared to conventional alternatives [2]. Despite these promising advantages, there remains a gap in our comprehensive understanding about the origin of the damping in plant fiber composites.
In this study, a multi-scale finite element method is proposed to assess the damping behavior of composite materials. The micromechanical approach yields the overall composite behavior based on properties of its constituents (fiber and matrix). This is achieved through an analysis of a representative volume element (RVE). On the other hand, the macromechanical approach involves replacing the heterogeneous structure of the composite with a homogeneous medium possessing anisotropic properties [3]. Homogenization plays a crucial role in multiscale modeling, serving as a method to derive the properties of a homogeneous model at a specific scale from a heterogeneous model built at a lower scale [4]. In the context of obtaining damping properties of unidirectional fiber reinforced composites, using homogenization techniques, computations are conducted in the frequency domain using COMSOL.
A complementary method for assessing the damping of composites involves experimental approaches. Commonly employed techniques include dynamic mechanical analysis (DMA) and modal analysis [5]. DMA is conducted at a lower frequency range, as compared to modal analysis, focusing on controlled volume fractions of fibers in both synthetic and bio-based composites, aiming to measure their viscoelastic properties. Modal analysis, performed under free-free boundary conditions and covering a broad frequency spectrum, is employed to identify the dynamic properties of the composites at the macroscale.
The developed model is then used to tailor the dynamic properties of the composite structure, which can further be validated experimentally. The aim is to obtain an optimal balance between rigidity and damping of the composite by optimizing key parameters, such as the volume fraction and orientation of fibers.
In this study, a multi-scale finite element method is proposed to assess the damping behavior of composite materials. The micromechanical approach yields the overall composite behavior based on properties of its constituents (fiber and matrix). This is achieved through an analysis of a representative volume element (RVE). On the other hand, the macromechanical approach involves replacing the heterogeneous structure of the composite with a homogeneous medium possessing anisotropic properties [3]. Homogenization plays a crucial role in multiscale modeling, serving as a method to derive the properties of a homogeneous model at a specific scale from a heterogeneous model built at a lower scale [4]. In the context of obtaining damping properties of unidirectional fiber reinforced composites, using homogenization techniques, computations are conducted in the frequency domain using COMSOL.
A complementary method for assessing the damping of composites involves experimental approaches. Commonly employed techniques include dynamic mechanical analysis (DMA) and modal analysis [5]. DMA is conducted at a lower frequency range, as compared to modal analysis, focusing on controlled volume fractions of fibers in both synthetic and bio-based composites, aiming to measure their viscoelastic properties. Modal analysis, performed under free-free boundary conditions and covering a broad frequency spectrum, is employed to identify the dynamic properties of the composites at the macroscale.
The developed model is then used to tailor the dynamic properties of the composite structure, which can further be validated experimentally. The aim is to obtain an optimal balance between rigidity and damping of the composite by optimizing key parameters, such as the volume fraction and orientation of fibers.