Micromechanical and experimental analysis of thermal conductivity of hemp-palmyra reinforced hybrid composites

Abstract

The present work investigates the longitudinal and transverse thermal conductivity of hemp and palmyra fiber reinforced hybrid composites to use as thermal insulation material in buildings. Investigations are carried in accordance with ASTM-E1530. A total of thirteen test specimens of hybrid composites were fabricated with different fiber weight percentages (0, 10, 20, 30, and 40 wt%) by varying the weight ratio of hemp and palmyra as 1:1, 1:2, and 2:1 using hand lay-up method. The transverse thermal conductivity is also determined by developing a mathematical model based on microstructural mechanics and laws of heat transfer. The experimental investigations of thermal conductivity are compared and validated with FEA, developed mathematical model and analytical methods available in the literature. The effect of fiber orientation, volume fraction and inter-facial thermal resistance to determine the longitudinal and transverse thermal conductivity is incorporated by using finite element analysis. Investigations revealed that longitudinal thermal conductivity decreased by 36.08% and transverse thermal conductivity decreased by 37.74% at maximum fiber loading of 40 wt%.