Predicting transverse thermal conductivity of flax-fiber using micromechanical model based inverse framework

• Published in: International communications in heat and mass transfer 2025-01, Vol.160, p.108375, Article 108375
• Main Authors: Subramanyam, V., Pandurangan, V., Nithyadharan, M.
• Format: Article
• Language: English
• Subjects: Flax fiber; Flax-epoxy composite; Inverse framework; Micromechanical model; Thermal conductivity; Woven fabric composite
• ISSN: 0735-1933
• DOI: 10.1016/j.icheatmasstransfer.2024.108375

The paper presents an inverse approach using a micromechanical model for predicting the transverse thermal conductivity of flax fiber, addressing the lack of standard testing protocols for characterizing natural fibers. The model predicts the transverse thermal conductivity of the fiber from experimentally measured properties of the flax-epoxy lamina. The inverse approach was validated using data corresponding to carbon-epoxy composite reported in the literature, with an error of less than 5 %. The transverse thermal conductivity of the flax fiber was estimated to be 0.87 W/m K, which is comparable to other natural fibers. The flax fiber properties were used to evaluate the thermal conductivity of the flax-epoxy lamina for a range of volume fractions, and a simplified non-linear regression equation was proposed. The methodology is further extended to predict the elastic properties of the woven fabric laminate using a multiscale homogenization approach. The proposed framework offers a reliable method for predicting the thermal properties of flax-epoxy composites, which forms the basis for thermo-mechanical analysis and design of automotive and aerospace components. [Display omitted] •Thermal conductivity of flax fiber is challenging to obtain experimentally.•Inverse framework for estimating the transverse thermal conductivity of flax fiber•Experimental studies on thermal conductivity of flax epoxy composite•Multiscale homogenization approach for woven-fabric composites