Abstract : Prediction of the pattern and distribution of a formulation filled into a package is a major challenge and of great industrial interest. In this project we will first develop a simple experimental setup in which a clear stream and colored stream are simultaneously filled into a rotating clear container through nozzles at the top. The two steams then spread towards the wall as alternate clear and colored layers. The pattern and distribution of the two streams in the varying operational parameters will be visualized and recorded. The multi-stream filling process of packages and a parametric study will be carried out using a CFD technique to help design of better products. Mr Wu Zhonghua , a PhD student in Prof. Mujumdar's group will collaborate on this work.

Abstract : Vacuum freeze drying is the most widely used freeze drying process for pharmaceuticals, biological products, etc. The main disadvantages of this technique are lengthy operation, very high fixed and operating costs. Preliminary studies show that vibrating bed dryer coupled with multimode heat input and selective adsorbent mixed with previously frozen particle would be a good option to overcome some of the aforementioned drawbacks of traditional vacuum freeze drying. The aim of this experimental project is to design, build and test an atmospheric freeze drying system coupled with a selective adsorbent to permit simultaneous application of conductive and radiant heat. A vortex tube will be used to provide convective freezing and atmospheric pressure drying coupled with radiant/conductive heating applied intermittently.

Abstract : Proton Exchange Membrane (PEM) Fuel Cells have been widely recognized as the most promising candidates for future power generating devices in the automotive, distributed power generation and portable electronic applications. The performance of PEM Fuel Cells is known to be influenced by many parameters, such as operating temperature, pressure and humidification of the gas streams. Therefore, it is essential to understand these parameter effects on fuel cell operation in order to improve the performance. Systematic experimental data are very valuable for fuel cell developers to optimize their operating conditions.

In this study, systematic experiments will be conducted on a single PEM Fuel Cell to provide fundamental parametric experimental data. The student is expected to build his/her own fuel cells based on the available resources. Pure hydrogen and air will be used in anode and cathode side respectively. Series of polarization curves with different fuel cell temperatures, humidification temperatures and back-pressure will be performed. The experimental data will then be compared with computational results obtained elsewhere for further analysis and verification.

Abstract: In view of the ever increasing levels of environmental pollution and thus a desire to replace the fossil-fuel-based economy with a cleaner alternative, the polymer electrolyte membrane fuel cell (PEMFC) has in recent years emerged as a prime candidate for automotive, portable and stationary applications. These fuel cells convert hydrogen or hydrocarbon fuels directly into electricity. High efficiency, low emissions, silent operation, no moving parts and a scalable system, etc are among the main advantages of fuel cells.

The objective of this study is to model the various transport processes including chemical reactions occurring within the heart of a PEM fuel cell and use this knowledge to enhance fuel cell performance. Simulation of the transport processes will be carried out by suitably adapting commercial CFD software.