Title: Experimental Investigation of heat transfer in 2-phase diabatic flow in inclined tubes

Student: AO Adelaja

Mentors: J Dirker and JP Meyer

Air- and water-cooled condensers with in-tube condensation of refrigerants are widely used in water chillers, air-conditioners, heat pumps, refrigeration of food and fresh produce, industrial processes and automobiles. Higher energy efficiency requirements, material and space saving consideration are motivations for optimal design of such systems, thus, a thorough understanding of diabatic 2-phase flow is required. This study aims to investigate the effect of the saturation temperatures, inclination angles and microfin enhancement as they affect the flow pattern, heat transfer and pressure drop in inclined tubes. The objectives of the study are to develop tools for the heat transfer coefficient and pressure drops during convective condensation in inclined tubes and to develop practical design guideline/ empirical relationship for design engineers of inclined condensers. 

Title: OPTIMAL CONFIGURATION FOR MAXIMUM CURRENT DENSITY FROM DIFFERENT TYPES OF FUEL CELLS

Researcher: Dr. Martins, Lauber

Supervisor: Bello-Ochende, T & Meyer, JP

Alkaline fuel cells (AFC) can also operate at low temperature as Polymer Electrolyte Membrane Fuel Cells (PEMFC), with the advantage of use non-nobles metals as catalysts. A mathematical and simulation model that accounts for electrochemical and thermal interactions of an AFC and PEMFC has been studied extensively the scientific community including the Thermo flow research group at the University of Pretoria.  So far, platinum has been used as catalyst on the electrodes of AFC and PEMFC, however the main goal is not to use this expensive metal as catalyst, but to use nickel instead, which will demand a combined effort with material scientists. The research project is concentrated in hydrogen and its applications using experimentally validated simulation models as tools for optimization and design of renewable/sustainable energy systems. My experience working with modelling and simulation of fuel cells contributes to projects involving the investigation of optimal configuration of single fuel cells and their application in power systems. Physical understanding and accurate application of the conservation laws related to mass, heat and electrochemical interactions in fuel cells is crucial for an optimal configuration; nanotechnology applied to membrane and electrodes has been pointed as a way to improve the performance of fuel cells.