Keynote Speaker I:
"Reverse Design of Ultrasonic Absorptive Coating for Delaying Supersonic/Hypersonic Boundary Layer Transition"

High-speed boundary layer transition control is a very crucial problem in the design of aerospace vehicles because heat transfer and surface friction in turbulent flow are extremely higher than that in laminar flow, resulting in severe requirement for thermal protection system (TPS) and low payload. In supersonic and hypersonic flight circumstances, forcing environment perturbations are commonly small and the boundary layer transition is dominated by eigenmode growth, such as Mack modes, crossflow instabilities, and  vortices. The last two types can be damped by shaping. With respect to Mack modes, the first mode can be stabilized by wall cooling, which, however, can destabilize the second mode. Since the disturbance frequencies of Mack second mode is larger than 100 kHz, ultrasonic absorptive coating (UAC) may be used to absorb the ultrasonic frequency fluctuations to suppress this mode [1].

For the supersonic/hypersonic boundary layer over a flat plate or a slender axisymmetric cone with zero angle-attack, Mack first mode dominates the boundary layer instabilities at low Mach number and the second mode gradually becomes the dominant mode as Mach number increases [2]. Substantial experimental, theoretical, and numerical studies have been carried out to investigate the effect of UAC on the second mode under high Mach number [3-6] and confirmed its stabilization effect. In addition, many optimized UAC structures have been proposed based on minimum reflection coefficient for ultrasonic frequency incident waves.

In this paper, a two-dimensional boundary layer on a flat plate with free stream Mach number of 4 and unit Reynolds number of  is considered; meanwhile a UAC composed of slits (Fig.1) is designed to delay the boundary layer transition. Fig. 2 shows Mack modes in this boundary layer without UAC. Firstly, we investigate the effect of UAC on the dimensionless angular frequencies and growth rates of Mack modes using linear stability theory (LST). The UAC admittance amplitude and phase angle are taken into account, rather than the reflection coefficient, since the phase angle has profound effect of Mack modes and is less studied. The regularity of the admittance amplitude and phase angle of a UAC is examined. According to these theoretical analyses, optimized parameters of the UAC structure are proposed with validation of the stabilization effect.

 

Bio-Sketch

Professor Wen received his Bachelor of Science degree from the Department of Mechanical Engineering at the National Taiwan University in 1986 and Master of Science and PhD from the Department of Aeronautics at the California Institute of Technology (Caltech), U.S.A. in 1989 and 1994 respectively. He worked at Caltech as a Research Fellow from February 1994 to July 1994 and then continued his teaching and research works at the Department of Mechanical Engineering at the Da-Yeh University, Taiwan. He was promoted to full professorship in February 2002. He had been the Chairman of the Department of Mechanical and Vehicle Engineering from August 1997 to July 2000, and the Provost from August 2004 to July 2006 in the Da-Yeh University, Taiwan. In August 2006, Professor Wen joined the Department of Aeronautics and Astronautics of the National Cheng Kung University (NCKU),
Taiwan, before joining the Department of Mechanical Engineering, The Hong Kong Polytechnic University in 2012 as professor. He is currently the associate head of ME department. Professor Wen has authored and co-authored more than 160 scientific papers, conference papers and book chapters. He was also awarded 14 patents. His current research interests are in the areas of (1) Hypersonic aerothermodynamics; (2)Shock/Droplet and Shock/Bubble Interactions; (3) Detonation; (4) Flow Control by plasma actuators on a delta wing; (5) Technology development of UAVs and MAVs; and (6) Ice Accretion. Professor Wen, currently an AIAA Associate Fellow and editor of the prestigious international journal—AIAA Journal and Shock Waves, serves as the vice chair of the technical committee of fluid mechanics, ASME and a member of, various key professional boards and bodies related to the Aerospace Engineering.

WEN Chih-Yung,
Professor of The Hong Kong Polytechnic University, Hong Kong

Keynote Speaker II:
"Optical Engineering – a new discipline for Mechanical Engineers"

Optical engineering is a new discipline which has evolved rapidly this century to harness the science of optics and the technology of photonics. With applications ranging from 3D imaging and 3D printing to x-ray CT scanners, there is virtually no sector untouched by this technology. Companies such as Google and Apple to Zeiss and Nikon to Alcatel-Lucent to Coherent and others are actively pursuing the capabilities on offer. So where do mechanical engineers fit into this scheme. Mechanical Engineers have strengths in design, manufacture and assembly and inspection and testing of instruments and systems. Hence with the proper training , we are at the forefront on optical lens and camera design and manufacture, assembly of microscopes and optical systems and testing and quality control of MEMS and nano-devices.
In this talk, I will take you through my journey through this exciting field overcoming administrative obstacles and challenges along the way. I will also highlight my current endeavors in this field as my focus moves from research to innovation to commercialization.

Bio-Sketch

Anand Asundi graduated from the Indian Institute of Technology, Bombay with a B.Tech (Civil Engg.) and a M.Tech (Aeronautical Engg.). Subsequently he received his Ph.D. from the State University of New York at Stony Brook. Following a research fellowship at Virginia Tech., he was with the University of Hong Kong from 1983 to 1996 as Professor in the Department of Mechanical Engineering. He is currently Professor and Director of the Centre for Optical and Laser Engineering in the School of Mechanical and Aerospace Engineering at the Nanyang Technological University in Singapore. His teaching area is in Optical Engineering and Engineering Mechanics with research interests in Computational Optical Metrology, Photomechanics and Fiber Optics Sensors. He has numerous patents, has published extensively and presented invited seminars/talks at various institutions and at international conferences. He is Editor of Optics and Lasers in Engineering and Fellow of SPIE, the International Society of Optical Engineers and the Institution of Engineers, Singapore. He is founding chair of the Optics and Photonics Society of Singapore, Asian Committee on Experimental Mechanics and the Asia Pacific Committee on Smart Materials and Nanotechnology. He has organized numerous conferences and served on the Membership, Scholarship/Awards and Presidential Asian Advisory committees of SPIE and its Board of Directors. He is also the founder and director of d’Optron Pte Ltd..

Anand Asundi,
Professor of Nanyang Technological University, Singapore (Director of d’Optron Pte Ltd)

Keynote Speaker III:
"TBA"

Abstract coming soon...

Bio-Sketch

Ph.D. in Mechanical Engineering ; M.Sc. in Manufacturing MA in Education Management ; Pg.D. in Education Training; B.A. (Hons) in Mechanical Engineering; B.A. in Production Engineering Member of the Institute of Electrical Engineers. Dr McAndrew spent 12 years in industry as a designer before entering academia. He has over 20 years of teaching experience in the UK, Europe, Middle East and Far East. He has supervised many PhD students and published extensively for over 20 years. He is the author of a book and Editor of a new Journal being produced with a focus on Aviation. Currently he is the Department Chair of Graduate Studies in the College of Aeronautics Worldwide at Embry Riddle Aeronautical University. His research interests are in Aerodynamics and Effective Education, which he has published extensively. He has presented at many Conferences and believes these are critical research meetings for those that are new to research and the experienced to mentor the next generation.

Ian McAndrew,
Professor of Capitol Technology University, USA

Plenary Speaker I:
"Unmanned Vehicle: Guidance, Control, and its Potentialities"

Unmanned vehicles, especially Unmanned Aerial Vehicle (UAV) has seen unprecedented growth during the last decade, with even more expectations for future utilization in a very wide spectrum of possible applications such as inspection in inconvenient or dangerous area. While benefiting from the growth, new challenges arises as improvement on structural design. We have developed a quad tilt wing UAV like a multicopter to widen application range of an unmanned system. The UAV is capable of vertical takeoff and landing like a helicopter and level flight like an airplane during a mission. On the other hand, Unmanned Ground Vehicle (UGV) has been actively used for exploration of unknown environment, disaster monitoring, and surveillance. The vehicle sometimes requires simultaneous localization and mapping in non-GPS environment, irregular ground traveling, and collision avoidance for an exploration. It is important for the vehicles to realize real time control, to have robustness against disturbances and to consider fault tolerance. In this talk, recent research work will be highlighted in this area, focusing on guidance and control of nonlinear dynamics of the vehicles. Furthermore, this talk will present work on formation flying of UAVs and cooperation of UAV-UGV for constructing efficiency system. Our work will also be presented with successful demonstration.

Bio-Sketch

Kenji Uchiyama received PhD degree in control of aerospace systems from Tokyo Metropolitan Institute of Technology. He is a professor at department of aerospace engineering of Nihon University. He was a member of editorial committee of the Japan Society of Aeronautical and Space Sciences. With over 20 years of experience in guidance and control of mechanical systems, he has published articles in the areas of micro electro mechanical systems, space robots, lunar landers, attitude control systems for small satellites, space rovers, and unmanned aerial systems. He was a visiting researcher of the University of Strathclyde and the University of Glasgow, and has collaborated with professors in the University.

Kenji Uchiyama,
Professor of Professor of Nihon University, Japan

 

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