Onur has recently graduated from the University of Brighton with a first-class honours degree in MEng Automotive Engineering, where he investigated Characteristics of Nanofluid Sprays and their Cooling Performance on a piston surface. A poster produced from the findings of this study was presented at the 29th European Conference on Liquid Atomization and Spray Systems (ILASS). Furthermore, during his studies, he had a chance to work in an electric vehicle conversion project where he focused on designing the thermal management system. The AAPS CDT provided the perfect opportunity to investigate these two areas of interest further in a collaborative and innovative environment. As an AAPS CDT student, he will be carrying out research in the area of Leidenfrost propulsion for cooling flows in AM parts. Outside of the University, he is a passionate racing and a football fan.
Cryogenics is a branch of science studying materials that undergoes phase change between -150 and -273 Degrees Celsius. Most popular examples for cryogenic materials are Oxygen,Nitrogen, Helium and Hydrogen.
Cryogenics have been widely employed as a part of multiple industries such as but not limited to: Aviation, Automotive, Medical and Storage industries. Examples of utilisation cases can be listed as: Rocket fuel and pre-conditioner, Fuel cell propulsion systems, cryosurgery and refrigeration units for cold cargo.
Leidenfrost effect is a physical phenomenon where, a liquid on a hot surface that is above its boiling point produces a vapour layer that acts as an insulation between the liquid and the hot surface. The vapour layer produced acts as an insulation limiting the heat transfer rate between the liquid and the surface. By utilising surface properties, the flow of Leidenfrost Droplets can be sustained which can be described as "Self-propelled Leidenfrost Droplets".
Due to the increasing consciousness around global warming and the request of reducing transportation emissions, propulsion systems are required to be more efficient and less polluting then ever. In support of this, commercial aviation and automotive companies have been seeking alternative propulsion solutions one of which is fuel cells which are powered by cryogenics resulting in clean propulsion without harmful emissions. Because cryogenic systems so far have only been used in specialised and limited life cycle applications in propulsion such as rocket fuels, long term effects and systems level applications in long term must be explored in order to commercialise such systems. Examples of such propulsion systems have been brought to market by multiple OEMs with the price being the largest penalty as well as the complexity, storage and weight challenges surrounding fuel cell systems.
The study will aim to explore the capability of utilising Self-propulsion of Cryogenics inside a Pipe mostly aimed at fuel delivery systems in order to understand the boiling characteristics and physical interactions with the internal pipe surface. The Self-propulsion inside the pipe is aimed to be achieved by the introduction of in-pipe structures to manipulate the flow during the Leidenfrost regime of the Cryogenic liquids to be utilised.
Onur's PhD study is planned to be conducted both in practical experimentation and simulation in order to verify and test varying conditions and flow regimes. Initially, the testing will begin with liquid nitrogen as a working fluid which will then be changed to liquid hydrogen. The reason for the utilisation of liquid nitrogen at the start of the study is to understand the cryogenic working environment and the challenges attached to it. Simulation studies will be employed in order to understand flow regimes that are not possible to replicate using practical means and to verify the results of the practical experimentation.
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