Title :

Passive Thermal Management and Some of Its Energy-Related Applications

Speaker :

Prof. Shwin-Chung Wong

Department of Power Mechanical Engineering

National Tsing Hua University (NTHU), Hsin-Chu, Taiwan, ROC

Venue :

Room 215, William M. W. Mong Engineering Building, CUHK

Date :

Nov 30, 2012, Friday
11:00 AM - 12:00 PM

Abstract :

Passive thermal management is required in some important engineering applications, such as natural-convection cooling of high-power LED lamps and fanless electronic equipment, etc. This talk will present the researches recently conducted in our lab at NTHU. The first part is on the development of concentrated high-power LED lamps, successful up to 200 W, utilizing passive thermal management. These lamps are embedded with a vapor chamber (a flat heat pipe) which effectively spreads the large amount of concentrated heat from the multi-chip LED. At this point, a series of unprecedented visualization experiments on heat pipes will be elaborated, as heat pipes are an important passive heat transfer device. Enhancement of natural convection from the aluminum horizontal plate-fin heat sink is another key to the success. The optimum design of the heat sink with perforations in the base plate is also discussed. The second part will introduce the development of a novel passively-fed methanol steam reformer (MSR). This design has been verified to yield high conversions with low CO product concentrations under a two-stage bi-fueled process. Furthermore, with a heat pipe applied in the packed-bed catalytic PROX CO remover, the CO concentration of the MSR product can be lowered to an acceptable level. These progresses make possible a high-energy-efficiency fuel-cell system which consumes hydrogen generated on-site by an MSR, and the MSR reutilizes the remaining hydrogen in the exhaust of the fuel-cell stack. Finally, our current study on the cooling of the CPU of fanless thin client PCs will be briefly discussed.

Biography :

Professor Shwin-Chung Wong joined the Department of Power Mechanical Engineering, National Tsing Hua University, Taiwan, since he received his Ph.D. from Penn State Univ., USA in 1988. His current research activities include engineering thermal management and hydrogen generation by catalytic methanol reforming.

    **************************************** ALL ARE WELCOME ****************************************

Enquiries: Ms. Winnie Wong, Department of Mechanical and Automation Engineering, CUHK at 3943 8337. *MAE Series (2012-13) is contained in the World-Wide Web home page at http://www3.mae.cuhk.edu.hk/maeseminars.php#mae.