Chapters authored
Compressive Stress Relaxation and Creep Properties of Synthetic Fiber and Regenerated Fiber Assemblies
Part of the book: Polyester
Effective Thermal Conductivity of Cupra and Polyester Fiber Assemblies in Low Fiber Volume Fraction
In this study, the effective thermal conductivity of staple fiber assembly for wadding use is measured using KES-F7 II Thermo Labo II apparatus. Sample used are cupra, polyester (with round and heteromorphic section), and polytrimethylene terephthalate (PTT) fibers. Heat flux to calculate thermal conductivity is measured including heat leakage from sidewall and is calibrated in the analysis. Results are analyzed by nonlinear regression method. Results are obtained as follows. Thermal conductivity curve is convex downward in low fiber volume fraction (<3%). Thermal conductivity, λ, is expressed as following equation, λ = Aφ + B/φ + C, where φ is fiber volume fraction, A and B are coefficients, and C is constant determined by nonlinear regression analysis. Based on this equation, the effective thermal conductivity is divided into three parts: Aφ, heat conduction in fiber; B/φ, radiative heat transfer; and C, heat conduction within air. By calibration, C component is divided into thermal conductivity of air, λair and heat leakage from sidewall of the sample frame. λair plays the most important role in thermal insulation property of fiber assembly, and component of heat conduction in fiber, Aφ, follows in higher fiber volume fraction. Component of radiative heat transfer, B/φ, is negligible small.
Part of the book: Impact of Thermal Conductivity on Energy Technologies