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Full-Text Articles in Engineering
Sustainable Smouldering For Waste-To-Energy: Scale, Heat Losses, And Energy Efficiency, Tarek L. Rashwan
Sustainable Smouldering For Waste-To-Energy: Scale, Heat Losses, And Energy Efficiency, Tarek L. Rashwan
Electronic Thesis and Dissertation Repository
Applied smouldering combustion is emerging as a highly energy efficient approach towards waste-to-energy. This thesis aims to better understand this potential by addressing a critical knowledge gap between laboratory scale smouldering research and large-scale applications. Altogether, new understanding in provided on the complex and dynamic interactions between the reaction zone (smouldering front) and the cooling zone (treated inert porous media) by integrating theory, experiments, analytical modelling, and global energy balance calculations. The experiments spanned a range of reactor sizes and smouldering conditions (from weak to robust) with dry (carbon) and wet (sludge) fuels mixed in sand. This work revealed that …
Dynamics Of The Phase Coupling For Flow, Heat And Mass Transfer In Conjugate Fluid/Porous Domains, Mahmoud Mohamed Mostafa Elhalwagy
Dynamics Of The Phase Coupling For Flow, Heat And Mass Transfer In Conjugate Fluid/Porous Domains, Mahmoud Mohamed Mostafa Elhalwagy
Electronic Thesis and Dissertation Repository
Porous media prevail in industry e.g. heat transfer equipment, drying, food storage and several other applications. Integrated in engineering, they form conjugate Fluid/Porous domains. Physical modelling requires characterizing the microscale heat and mass (moisture) transfer interstitially within porous media and their macroscale counterparts across regional interfaces. Characterizing turbulence and its effects on phase coupling is often needed too. The modeling literature survey shows phase coupling assumptions depending on empiricism, phase equilibrium and lack of generality. Modeling of the dynamic variations for the modes of phase exchanges, i.e. heat, mass and heat accompanying mass exchanges, on both scales and generic turbulent …
A Model For Complex Heat And Mass Transport Involving Porous Media With Related Applications, Furqan A. Khan
A Model For Complex Heat And Mass Transport Involving Porous Media With Related Applications, Furqan A. Khan
Electronic Thesis and Dissertation Repository
Heat and mass transfer involving porous media is prevalent in, for example, air-conditioning, drying, food storage, and chemical processing. Such applications require non-equilibrium heat and mass (or moisture) transfer modeling inside porous media in conjugate fluid/porous/solid framework. Moreover, modeling of turbulence and turbulent heat and mass transfer becomes essential for many applications. A comprehensive literature review shows a scarcity of models having such capabilities. In this respect, the objectives of the present thesis are to: i) develop a formulation that simulates non-equilibrium heat and mass transfer in conjugate fluid/porous/solid framework, ii) demonstrate the capabilities of the developed formulation by simulating …
Numerical Analysis Of Two Phase Flow And Heat Transfer In Condensers, Pooya Mirzabeygi
Numerical Analysis Of Two Phase Flow And Heat Transfer In Condensers, Pooya Mirzabeygi
Electronic Thesis and Dissertation Repository
Steam surface condensers are commonly used in the power generation industry and their performance significantly affects the efficiency of the power plant. Therefore, it is vital to acquire a better understanding of the complex phenomena occurring inside condensers. A general three-dimensional numerical model is developed in this study to simulate the two-phase flow and heat transfer inside full-scale industrial condensers with irregular tube bundle shapes. The Eulerian-Eulerian two-phase model is selected to simulate gas and liquid flows and the interaction between them. A porous media approach is adopted to model the presence of large number of tubes in the condenser. …
Numerical Modelling Of Species Exchange In A 3d Porous Medium: Modelling Exchange Within The Human Lung, Chelsea E. Johnson
Numerical Modelling Of Species Exchange In A 3d Porous Medium: Modelling Exchange Within The Human Lung, Chelsea E. Johnson
Electronic Thesis and Dissertation Repository
The volume-averaged oxygen transport equation is closed using a volume-averaged form of Fick’s law of diffusion between the air and tissue to simulate species exchange within the lungs’ alveoli using a computational fluid dynamics (CFD) 3D conjugate domain model. Pore level simulations of a terminal alveolated duct are used to determine that the transport of inhaled oxygen from the cluster inlet to the alveolar walls is diffusion dominated. The resistance to oxygen diffusion into the tissue is found to be a function of the tidal volume and tissue transport properties, with a maximum respiration frequency at which the full amount …
Numerical Modelling Of Transport In Complex Porous Media: Metal Foams To The Human Lung, Christopher T. Degroot
Numerical Modelling Of Transport In Complex Porous Media: Metal Foams To The Human Lung, Christopher T. Degroot
Electronic Thesis and Dissertation Repository
Transport in porous media has many practical applications in science and engineering. This work focuses on the development of numerical methods for analyzing porous media flows and uses two major applications, metal foams and the human lung, to demonstrate the capabilities of the methods. Both of these systems involve complex pore geometries and typically involve porous domains of complex shape. Such geometric complexities make the characterization of the relevant effective properties of the porous medium as well as the solution of the governing equations in conjugate fluid-porous domains challenging. In porous domains, there are typically too many individual pores to …