V o l . 3 , N o . 1 , J a n u a r y 2 0 0 8

N e w s l e t t e r o f E n g i n e e r i n g S c i e n c e P r o g r a m m e

M o n d i a l o g o E n g i n e e r i n g A w a r d

The team comprising ESP students Tan Huei Ming, Tan Yi Han, Muhd Ibnur, and Set Ying Ting, Mechanical Engineering student Veerappan Swaminathan and Mumbai University Institute of Chemical Technology (MUICT) students Vaibhav Tidke and Darshan Metha won the prestigious Daimler-UNESSO Mondialogo Engineering Award 2006-2007 for their project titled “Economic Improvement of Indian farmers by Solar Processing of Agro-Products”.

The cash prize of 20,000 Euros (about S$42,000) provide the seed money to help bring the project to realization. This award is the top honour awarded to the top 10 teams out of 809 that registered for the preliminaries. The pro-ject proposes to design and implement a fruit-drying system that makes use of solar energy for this process to reduce the high percentage loss of fruit crops, hence allowing farmers to preserve a portion of their fruits to be sold out-of-season or exported in order to ensure higher incomes. Mondialogo is the world's largest com-petition for young engineers with ideas that can change the world. Mr Oliver Michels, a consultant for Daimler – the event organizer in partnership with UNESCO said “The concept is to form intercultural teams of the brightest minds in the world to propose better living conditions”. On behalf of the team, Mr Veerappan said, "The competition field was very tough and there were many excellent projects from all over the world. It was a great honour to win this competition”. He thanked their mentors Prof Arun Mujumdar (Mechanical Engineering Department) and Mr. Shek Mohammod Atiqure Rahman (PhD student) for their invaluable sup-port and assistance on their project proposals. The support given by Daimler Singapore was equally invaluable in many ways and the team is very grateful for it. The project team will be looking forward to a partnership with them on energy initiatives if the opportunity arises in the future.

Prof Mujumdar said of our NUS engineering team: “Even though they were only second year students (taking mostly science courses rather than engineering courses) they made up by sup-plementary guided learning. The Mumbai group had the essential background knowledge as senior chemical engineering students in India's top ChE department. Thus, it was the synergy between the two teams that helped them secure the top place -even when completing with PhD student teams from many top universities of the world.”

E d i t o r i a l C o m m i t t e e

Editor: Prof CM Wang Secretaries: Ms Lillian Zheng Ms Sharmilah Salleh Contributors: Prof CM Wang Dr Erik Birgersson Dr Palani Balaya Dr Ho Ghim Wei Ms Helen Lee Ms Alexandra Toumar Mr Thomas Ang Mr Ryan Teo Mr Loh Chee Mun Mr Zhang Teng Mr Tan Huei Ming

Standing– Yihan, Ying Ting, Veerappan, Huei

Ming & Ibnur. Sitting– Prof Wang, Prof Mu-

jumdar, Prof Ramakrishna, Prof Khursheed

N e w C h a n g e s i n E S P The Engineering Science Programme (ESP) has recently been reorganized as an integrative educational (undergraduate degree) programme with a view to stream-line its activities. A core of about 12 faculty, hosted by various depart-ments in the faculties of engineering and science, designated as ESP Associates, will be responsible for supervising and mentoring ESP students, running the ESP teaching laboratories, serving in outreach activities, liaising with universi-ties and organizations with regard to student exchange and internship pro-grammes as well as attending to accreditation needs. The new director ap-pointed for the reorganized ESP is Prof Wang Chien Ming, while the deputy di-rector is A/Prof Anjam Khursheed and Prof Frank Watt is the FoS ESP Coordina-tor.

In the long term, ESP would evolve into a programme where departments may wish to use it to mount new multi-disciplinary focus which on its own is hard to pursue. By viewing from this per-spective, the proposed new structure will enable ESP to become a wonderful test-bed of educa-tional initiatives integrating science and engineering.

C o n t e n t s

Mondialogo Engineering Award 1

New Changes in ESP 1

ESP Staff Members Celebrate Christ-mas and New Year

2

Student Exchange Programme Agree-ment with Osaka University

2

Design of Industrial Scale Dryer 3

Carbon Nanotube: Properties, Appli-cations & Fabrication

4

Energy Systems Laboratory Equipment

5

Thomas Ang—Laboratory Technologist

5

News Bits 6

List of completed UROP projects 6

Students’ Corner 7

Prof Wang

To celebrate Christmas and New Year, the ESP staff gathered at the Bridge Restaurant of the Singapore’s Yacht Club for lunch. The Yacht Club venue enhances the joyful occasion and the taste of the food with its beautiful view of the sea and the boat marina. The staff also took the opportunity to thank Prof Reddy for his significant contributions to ESP by presenting him with a token of apprecia-tion. Under Prof Reddy’s headship, ESP obtained a provisional accreditation from the Engineering Accreditation Board of Singapore and has attracted two batches of top students to read the engineering science programme.

E S P S t a f f M e m b e r s C e l e b r a t e C h r i s t m a s a n d N e w Y e a r

V o l . 3 , N o . 1 , J a n u a r y 2 0 0 8 Page 2

The Faculty of Engineering through Engineering Science Pro-gramme (ESP) has just signed the Memorandum of Understanding and Agreement for Exchange Programme for Undergraduate and Postgraduate Students with the Graduate School of Engineering Science, School of Engineering Science, Osaka University. This Agreement is effective for five years and is in force on 1 January 2008.

NUS ESP is privileged to co-partner with the Graduate School of Engineering Science, Osaka University to enhance the educational and academic research of both universities. There are 10 courses offered by the four departments in the School of Engineering Science:

1) Department of Electronics and Materials Physics – Electronics Course/Materials Physics Course

2) Department of Chemical Science and Engineering – Chemistry Course/Chemical Engineering Course

3) Department of Systems Science – Mechanical Science Course/Systems Science and Applied Informatics Course

Biophysical Engineering Course

4) Department of Information and Computer Sciences – Computer Science Course/Software Science Courses

Mathematical Science Course

A maximum of two students will be exchanged between the universities in each academic year. There are two semester in the academic year for Osaka University, i.e. Semester 1: April to August and Semester 2 : October to February. The courses are conducted in Japanese. Already an ESP student has indicated his interest to participate in this exchange programme for AY2008. We are confident that our students will acquire new skills and further enhance their knowledge and widen their horizons from this exchange.

For more information on the courses offered by Osaka University, please visit

http://www.es.osaka-u.ac.jp/eng/dept/index.html.

Student Exchange Programme Agreement with Osaka University

Himeji Castle, Osaka

In front of Singapore Yacht Club In the Bridge Restaurant Happy faces after an enjoyable lunch

As part of the ESP philosophy of integrating hands-on engineering design with the learning of basic scientific principles, Year 2 stu-dents are required to read the ESP2109 Design Project I module. The module consists of two projects, determining mechanical proper-ties of materials (See earlier article by Aveline Foo on “Designing Our Own Experiments to Determine Young’s Modulus“, Pulse Oct 2007) and heat and mass transfer. For the second half, students are required to produce design guidelines for a dryer that can process 500kg of a selected agricultural product daily for a client.

In order to accomplish this objective, a small test facility was built to study the drying kinetics of muskmelon (Cucumis melo). After a cou-ple of iterations, our group settled with a final design that is based on optimal drying parameters (see Figure 1). Note the Energy Recovery Device (ERD) that harnesses the kinetic energy of exhaust air to power drying tray is to ensure uniform drying across fruit samples.

From the experimental results obtained, a theoretical model is con-structed and used to develop a numerical model which is imple-mented in COMSOL Multiphysics to predict the drying kinetics over a range of drying parameter values. Fluid flows within various drying chamber geometries are analyzed using Computational Fluid Model-ing (CFD). Figure 2 shows the cross-sectional temperature distribu-tion in an uninsulated drying chamber. This finding illustrates the im-portance of insulation for uniform drying and energy efficiency. Aerogel’s insulating properties are ideally suited for this purpose, but cost is a major problem. Cheaply produced aerogels could save the drying industry millions of dollars in electrical bills.

Finally, with the optimal parameter values and drying chamber geometry in hand, our team produced a design guideline that meets the given requirements. Given the limited nature of our study and open-ended nature of our project, our design guideline is created with flexibility, redundancy and fault-tolerant to account for model uncertainties, client preferences and unforeseeable operational challenges.

All in all, the project is a tremendously immersive experience in design, from the management of design constraints, conducting research and analysis, engage in problem solving, creating design specifications to presenting a design idea. It was definitely a memorable experience and good preparation for future projects.

Article is contributed by Loh Chee Mun, Tan Huei Ming, and Zhang Teng, 2nd year ESP students.

V o l . 3 , N o . 1 , J a n u a r y 2 0 0 8 Page 3

Design of Industrial Scale Dryer

Figure 3 – Simulated airflow within a honeycombed drying chamber with con-verging and diverging sections

Figure 4 – A 3D Representation of a possible closed-loop dryer configuration

Figure 1 - Apparatus setup used

Figure 2 – Cross-sectional temperature distribu-tion in an uninsulated drying chamber.

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C a r b o n N a n o t u b e s : P r o p e r t i e s , A p p l i c a t i o n s a n d F a b r i c a t i o n

A r t i c l e c o n t r i b u t e d b y P r o f C M W a n g , M s Y Y Z h a n g a n d D r G W H o

Discovered by Iijima of the NEC Laboratory in Tsukuba, Japan in 1991, carbon nanotubes are cylindrical structures based on the hex-agonal lattice of carbon atoms that forms (CNTs) crystalline graphite. Owing to their atomic structures, CNTs possess superior me-chanical, electronic, and thermal properties. For example, carbon nanotubes have Young’s modulus of approximately 1 TPa and ten-sile strength of about 60 GPa, which are much larger than those of steel. Owing to the excellent flexibility, CNTs can sustain extreme bending, twisting or buckling and recover their original structures upon the removal of the external loads. CNTs can be metallic or semiconducting depending on their geometry structures. The metallic nanotubes can convey an electrical current density of more than 1000 times that of metallic counterparts such as silver and copper. CNTs are also a more superior conductor than copper with thermal conductivity up to 6000W/mK at room temperature. The unique combinations of these outstanding properties make CNTs excellent candidates for applications in nanocomposites, nanodevices and nanoelectronics.

The first major commercial application of MWCNTs is expected to be realized in polymer composites as electrically conducting com-ponents. The conductivity can be achieved under low loading without degradation of other performance aspects, such as mechanical properties and the flow viscosity needed for thin-wall molding applications. The incorporation of CNTs into plastics can potentially enhance the overall elastic modulus and strength. For example, a mere 2% SWCNTs embedded into plastics leads to 3.5 times in-crease in the Vickers hardness while 1% SWCNTs doubles the thermal. It has also been reported that by embedding 1% MWCNTs in a polystyrene matrix, one can expect significant increases in the overall elastic modulus and strength of the composite by approxi-mately 35-42% and 25%, respectively.

Owing to the high electrochemically accessible surface area of porous nanotube arrays combined with their high electrical conduc-tivity and remarkable mechanical properties, CNTs can be used as electrodes for devices such as super capacitors, actuators, and lithium batteries. Super capacitors with CNT electrodes possess higher power capacities than batteries and much higher storage ca-pacities than ordinary capacitors. Because of their superior thermal stability, CNT-based actuator can operate at temperatures up to 3500C, and operation above 10000C could be expected. There is also a possibility to use CNTs as electrodes in lithium batteries due to their high reversible component of storage capacity at high discharge rates.

In addition to the above-mentioned applications of CNTs, other potential applications of CNTs are probes in scanning-probe micros-copy and atomic force microscopy with the added advantage of chemically functionalized tip; efficient and stable electron field emit-ters due to their large aspect ratios and naturally formed nanoscale-diameter; building elements for space elevator; gas and mole-cule sensors; and tiny tweezers for nanoscale manipulation.

There are many ways to fabricate or grow carbon nanotubes. The common methods are:

• Arc discharge method-arc vaporization of graphite rods. This method needs a high current of 50A to 100A, driven by a potential difference of about 20 V, to create a high temperature discharge between the two graphite electrodes. This method also requires purification since other carbonaceous products are produced simultaneously. However, the yield is rather high and it can pro-duce a good amount of single-walled nanotubes.

• Laser ablation. A pulsed laser is used to vaporise a graphite source and catalytic mixture in a reactor at high temperature of 12000C while an inert argon gas is admitted into the chamber. This method has a yield of 70% with mainly single-walled carbon nanotubes and needs intensive purification.

• Chemical vapor deposition. A classical method of flowing hydrocarbons over substrate with a layer of metal catalyst particles such as iron, nickel, and cobalt. The diameters of the nanotubes can be controlled and confined by the size of the metal parti-cles. The substrate is heated to about 700°C to disassociate the hydrocarbon gas and initiate the growth of nanotubes at the sites of the metal catalyst. An example of the equipment using the chemical vapor deposition method is shown in Fig. 1 and the carbon nanotubes that are grown by using this equipment are shown in Fig. 2.

Other less common methods include electrolysis, solid pyrolysis, diffusion flame synthesis, solution route etc.

Fig. 1 Equipment for growing carbon nanotubes via chemical vapor deposition is housed in the

ESP multidisciplinary project laboratory

Fig. 2 Carbon nanotubes grown from chemical vapor deposition method by our ESP students

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T h o m a s  A n g— E S P   L a b   T e c h n o l o g i s t  

Thomas graduated from Singapore Polytechnic in 1996 with a Diploma in Mechanical Engineering, majoring in Engineering Systems Design. In June 2007, he left his job in the Centre for Remote Imaging, Sensing & Processing to join ESP. He hopes to pass on his knowledge and working experience to ESP students who will be taking up this new and very exciting programme. He once attended a talk by Dr Allan Lee (Lead Engineer for NASA’s Cassini-Huygens project) where he learned that scientists and engineers in the team could not always see eye-to-eye on certain issues and problems. With ESP, he envisaged that ESP graduates may become the link between the two individuals.

He has been assigned to take care of the ESP multidisciplinary project lab. He was involved in the 2nd year ESP design projects and look forward to assisting ESP students in future exciting projects as he is very interested in R&D work.

His hobby is bowling. He is currently the Team Captain/Bowling Convenor for the NUS Bowling Staff Team. The bowling team has taken part in various competitions in 2007 and their best showing hitherto is being the only tertiary institution to qualify for the fi-nals of the Public Service STAR Games in June 2007. The team came in 11th out of 20 teams. Thomas is still striving for the perfect game and he is only 21 pins away from that target.

E n e r g y S y s t e m s L a b o r a t o r y E q u i p m e n t

ESP has four specializations and energy systems is one of them. The multi-disciplinary laboratory is equipped with necessary facilities to carry out design projects in conventional as well as sustainable energy systems. ESP 2nd year students have recently completed their design project on drying of fruits through convective heating processes. In the 3rd year, the students are expected to undertake a ma-jor design project in the area of sustainable energy systems such as fuel cells, solar cells and lithium battery. Since January 2007, we have been acquiring necessary equipment for synthesizing nanocrystalline oxide systems, transport measurements and fabricating solar cells, fuel cells and lithium batteries. The equipment include:

⇒ The fume chamber, tube and box-type furnaces with programmable temperature controllers for both solid state reaction as well as calcinations under vacuum/inert atmosphere up to 1200oC.

⇒ Keithley-electrometer, current and voltage source meters and high resolution voltmeters with the capability of interfacing with computers for measuring the performances (I-V curves) of the solar cells as well as fuel cells and transport properties such as electronic/ionic conductivity and diffusion coefficients, essential for optimizing the performances of these devices.

⇒ A glove box system to assemble lithium batteries using Sweglock cells. This glove box provides an inert (argon) atmosphere so that air-sensitive lithium or non-aqueous electrolytes could be handled safely during the fabrication of lithium battery cells. Another advantage of this glove box system is that it has dual access on both front and opposite sides so that two students could assist each other during a group project. This inert box also includes a crimping machine for assembling batteries using coin cells - which have certain advantages over the Sweglock cells.

⇒ An Arbin MT2000 battery tester with 16 channels, that enables 16 lithium batteries to be tested simultaneously.

In sum, the energy systems laboratory is well equipped for the design projects related to energy systems which brings relevant funda-mental knowledge and hands-on experience to our engineering science students and prepares them for advanced R&D based indus-trial career in the future.

Arbin battery tester Dr Palani assembling battery in the glove box

Page 6 V o l . 3 , N o . 1 , J a n u a r y 2 0 0 8

News Bits

Professor CM Wang was recently awarded a research grant of $180,000 from Lloyd’s Register to conduct a re-search study on the connection system for very large floating concrete modules on the sea. This research is prompted by the urgent need to develop a robust and reliable connection system for concrete floating modules that are 20 m high and connection length of some 100 m. The floating modules when assembled on the sea form a super-large floating fuel storage facility.

List of completed UROP Projects

Dr Daniel S Pickard has been awarded the NUS Young Investigator Award (YIA) in Decem-ber 2007 by the office of Deputy President (Research & Technology). The award offers research funding to highly promising young faculty members.

Under the YIA, Dr Pickard will initiate a plasmonics research programme at NUS which ex-ploits his expertise in plasmonics, low work-function materials and charged particle optics to explore new methods of imaging and probing plasmonic devices. The field of plasmonics is aimed at harnessing the unique properties of surface Plasmon polaritons (i.e. collective charge oscillations excited on a metal surface) to mould the flow of light on the nanoscale, enabling radically new devices and functions.

Potential applications of plasmonic devices span many disciplines including high-speed nano scale interconnects, meta-materials, chemical and biological sensing, sub-wavelength optics and waveguides, near-field-optical molecule trapping, high-density data storage, and the enhancement of non-linear effects, to name a few.

At the heart of Dr Pickard’s programme is a state-of –the-art photoemission electron micro-scope (PEEM), a multi-million dollar instrument which he has recently brought to NUS. With the support of the YIA, Dr Pickard will enhance this microscopy’s capability to enable the

imaging of plasmonic devices with unprecedented spatial and temporal resolution. When the enhancements are com-pleted, the PEEM will be the only instrument of its kind in the world and will provide critical information needed for valida-tion of plasmonic device functionality, comparison with theoretical models, as well as tremendous potential for new dis-coveries.

Dr Pickard with his PEEM

ESP Student Title of UROP project Supervisor

Seah Wei Qi Vibration of initially stressed nonlocal Euler-Bernoulli beams Prof CM Wang

Eunice Koh Passive Magnetic levitation Prof Khursheed

Wang Ying Passive Magnetic Levitation (Maglev) and Eddy Current Prof Khursheed

Li Peifeng A study of the effect of flow-distributor geometry in the cathode of a PEM fuel cell Dr E Birgersson

Zhang Teng Analysis of the gas diffusion layer in a PEM fuel cell Dr E Birgersson

Ryan Teo Preliminary study on thermal management of Lithium-ion batteries used in AUVs Dr E Birgersson

Chow Siew Wei Two-dimensional Quantitative Analysis of the Effect of Gas Channel Geometry on a Proton Exchange Membrane Fuel Cell

Dr E Birgersson

Liu Licheng Modeling of free breathing PEM fuel cells Dr E Birgersson

Tan Wenyou Synthesis and characterization of iron oxide (Magnetite) nanocrystals (Part 1) Dr GW Ho

Lee Zhihan Synthesis and characterization of iron oxide (Hematite) nanocrystals (Part 2) Dr GW Ho

Danny Chua Synthesis and characterization of vertically aligned carbon nanotubes using PECVD Method

Dr GW Ho

Siah Sin Cheng Nanocrystalline LiFePo4 as cathode material for lithium battery applications Dr B Palani

Cai Dingyan Nanostructured materials for lithium storage Dr B Palani

Melvin Fong Experimental Investigations of separation of Air from Two -Phased Mixture Dr SD Pang

Loh Chee Mun Effect of Grometry and Orientation of Encapsulated Healing Agent on Self - healing Process

Dr SD Pang

Aditi Sridhar Separation of Air-Water Mixture Through A Micro-Channel return bend apparatus; a Numerial Analysis

Dr SD Pang

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S t u d e n t s ’ C o r n e r E S P   S t u d e n t s  V i s i t   t o   I H P C  

1 4 t h  D e c e m b e r   2 0 0 7  

On the 14th Dec 2007, IHPC kindly welcomed a large group of ESP students with their friendly researchers and “wow-ed” us with their state-of-the-art technology.

The morning kickstarted with inter-esting lectures on the work that is being done at IHPC with relevance to our specializations. Students were given a preview of the trends in bio-modeling, computational chemistry, computational quantum mechanics and photonics technol-ogy. The enthusiasm shown by the guest speakers probably ignited the passion in us that day to pursue research.

After a short tea break, students were treated to the large 3D visualization display of the various projects done at IHPC. Several students were so absorbed that they tried to reach out in the air for the computer-generated molecules.

This memorable event would not have been successful without the support of Dr. Raj Thampuran, the Executive Director of IHPC, and the help of Dr. Chee Chin Yi from IHPC. We believe that next year’s event will be even more successful.

Students being shown a 3D real-time visualization

ESP Year 2

For any enquiry or feedback, you may contact:

Engineering Science Programme National University of Singapore 7 Engineering Drive 1, E3A #04-17 Singapore 117574

Fax No.: (65) 6775 4710 Tel No.: (65) 6516 5408 Website: www.esp.nus.edu.sg

Having (most) of the midterm exam and projects behind them, ESP students celebrated by having with a barbecue at Prince George's Park Residences. The food came just in time, however, and by the end of the evening, everyone was thoroughly fed and watered. The classes and their lecturers all had a great evening relaxing and getting to know each other outside of a classroom setting, and the everyone had a lovely time. The evening party was also a chance for the year 1 and 2 students to interact with each other. Despite both groups setting up geographically apparent camps on opposite sides of the barbecue area, as was to be expected, there turned out to be plenty of junior-senior mingling, and so the barbecue was a great success in that respect.

Several lecturers also took the time to come down and chat with the students and (like the students who attended) to get some free food. A/Professor Anjam Khursheed gave a talk on the overseas exchange opportunities available to ESP students in the coming years. This was much appreciated and the talk was repeated due to popular demand. ESP students have the opportunity to go overseas for 1 semester in their third year and study in universi-ties all over the world. Approximately 30% of the ESP cohort is given a place on SEP, which is considerably higher than other engineering departments. Needless to say, the students welcome this opportunity and are excited to explore their options as third c year comes closer for the first batch of NUS engineering scientists. This event saw the ESP cohort get to know each other more as a group and get to know their current and future lecturers. It was a great break before the looming final exams.

S t u d e n t s ’ C o r n e r

P r o f K h u r s h e e d & E S P S t u d e n t s

E S P s t u d e n t s B B Q

Y e a r 1 s t u d e n t s Y e a r 2 s t u d e n t s

E S P   S t u d e n t s   B B Q   S e s s i o n