Experimental and Theoretical Investigation of Heat and Mass Transfer Processes in Porous Media
thesisposted on 01.12.2019, 00:00 authored by Wenshuo Zhang
The present work aims at the further understanding of peculiarities of heat and mass transfer in porous media by the experimental and theoretical approaches. Chapters 4, 5 and 6 are devoted to the mass transfer processes in non-deformable porous materials. In these three chapters, the adsorption/desorption processes during the diffusion mass transport and the detection methods of the released vapor are studied for such porous materials as sand and clay. Highly sublimating materials, such as camphor and naphthalene, are buried in these porous media and used as a model sublimating vapor source. In relation to the experiments, theoretical/numerical models are also developed in these three chapters. Chapters 7- 10 have the heat transfer process in porous deformable nonwovens in focus, which is relevant for the enhancement of mechanical properties using thermal bonding. Tensile testing and blister testing are applied to measure the mechanical properties and the cohesion energy, respectively, of different thermally-bonded nonwovens. Several models related to the descriptions of nonwoven properties and the industrial calender thermal bonding process are developed. Heat and mass transfer mechanisms in vegetation in forest fire are explored experimentally and theoretically in chapters 11 and 12. Chapter 11 explores volatiles and water vapor ejection from pores during biomass burning in forest fires, and chapter 12 studies the velocity of flame propagation of the canopy fire in a model system. Conclusions are drawn in chapter 13.