Executive Summary : | This project investigates the instability of pipe flow through a porous medium under local thermal non-equilibrium (LTNE) conditions. This is a crucial problem in fluid dynamics due to its applications in heat removal, nuclear/pebble-bed reactors, gas and oil production, and heat exchangers. Two situations occur in convection through a porous medium: local thermal equilibrium (LTE) and LTNE. The LTE approach is widely adopted, while LTNE theory is vital for advancements in sciences and technologies, such as food technology and microwave ovens. The LTNE situation is particularly useful in porous metal foam for rapid heat exchange and energy absorption in computer chips and heat pipes. The project aims to study the influence of LINE parameters on flow instability characteristics and mechanisms in a vertical pipe. The non-isothermal parallel flow due to buoyancy force and external pressure gradient is considered, and the temperature of the pipe wall varies linearly with the z-axis. The main objectives of the project include studying the influence of LTNE parameters, the simultaneous impact of LTNE parameters and Prandtl number, the simultaneous influence of LTNE parameters, anisotropic permeability, and medium inhomogeneity, and the finite amplitude instability of pipe flow through porous media under LTE and LTNE conditions. |