Hygrothermal coupled modeling and behavior analysis of natural fiber-reinforced tubular composites

Abstract

The mechanical properties of natural fiber-reinforced composites (NFRCs) are susceptible to the coupled effect between environmental temperature and humidity. However, the coupled system for the heat and moisture field in NFRCs remains unclear. In regard to this, this paper presents hygrothermal coupled modeling of natural fiber-reinforced tubular composites (NFRTCs), considering the correlation between natural fiber aggregation, matrix contents, and porosity. The transient hygrothermal field and distribution in NFRTCs are predicted using the differential quadrature method. The predicted results are verified by the comparison with the experimental data in the literature. Through the proposed model, the effect of hygrothermal coupling, boundary conditions, fiber aggregation, porosity, and structural dimensions on the hygrothermal responses and distributions are analyzed in detail. The results show that temperature and moisture fields decrease significantly when the hygrothermal coupling or the hygrothermal convection boundary condition is used. In addition, hygrothermal field distributions gradually decline with the increasing fiber weight fraction, outer-to-inner radius ratio, and porosity coefficient, as well as the smaller fiber aggregation parameter. These results can serve as a guideline for the design and manufacturing of reliable NFRTCs subjected to hygrothermal environments.