Determination of thermal conductivity of baled agricultural biomass

Abstract

Modeling of transport phenomena in materials with porous bed features requires thermophysical properties, such as porosity, permeability and thermal conductivity be known. The paper presents experimental data obtained in the course of investigation focused on analysis of stagnant thermal conductivity of biomass. Experiments were conducted using a custom designed and constructed experimental setup and implementing original experimental procedure. Results obtained enabled stagnant thermal conductivity of biomass to be determined for different biomass porosity values. Analysis of the experimental data enabled functional dependence of stagnant thermal conductivity on porosity to be determined, with porosity varied in a range 0.50-0.85. Results obtained indicate that reduced bed porosity, down to the value of 0.65, causes stagnant thermal conductivity of the bed to be reduced. Further porosity reduction, below the value of 0.65, results in increased stagnant thermal conductivity of the bed. Experimental procedure developed shall be useful for gathering experimental data on different materials planned to be analyzed when examining transport phenomena occurring during combustion of biomass bales. In addition, data to be acquired shall be helpful in modeling the transport phenomena associated with combustion in porous beds.