CFD simulations of heat flow through multilayer biocomposites containing natural fibers, aerogel and Parylene C coatings intended for protective gloves supported by micro-CT structural analysis

Primary goal of presented research was to investigate the relationship between microstructure and thermal insulation properties of biocomposites used in thermal protective gloves, based on heat flow simulations. Multilayer biocomposites were constructed using natural fiber fabrics and included a thermal insulation layer composed of aerogel formed using a Parylene C coating deposition technology. Based on microtomography analysis, parameters of the biocomposites were determined. These parameters were used to design 3D models of the biocomposites to study their thermal insulation properties based on finite-volume heat flow modeling. The usability and accuracy of the designed biocomposite models were verified by comparing the simulation results with the experiment in which the biocomposites were exposed to contact heat under typical operating conditions. The obtained modeling results correlated with the experiment, and the temperature differences between the experimental and modeled values ranged from 1.1% to 2.3%, depending on the complexity of model geometry and taking into the anisotropy of thermal conductivity in natural fibers and the delamination of the biocomposite layers. The simulation results demonstrated the effectiveness of the aerogel layer, which, depending on the composite, retained between 77% and 85% of the heat flowing through the composite.