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me.postech.ac.kr ● Faculty of the Department of Mechanical Engineering

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Flow Physics and Engineering

Dong Hyun You

Education Ph.D. 2004 Stanford UniversityM.S. 1998 Seoul National UniversityB.S. 1995 Yonsei University

Experience 2012 - Associate Professor,

POSTECH2008 -2012 Assistant Professor,

Carnegie Mellon University2010 Visiting Professor,

Stanford University2005 - 2009 Senior Research Scientist,

NASA-Stanford Center for Turbulence Research

2004 – 2005 Postdoctoral Research Fellow, NASA-Stanford Center for Turbulence Research

Contact Tel: +82-54-279-2191Fax: +82-54-279-3199E-mail: dhyou@postech.ac.kr

Prof. You’s research is concentrated on high-fidelity simulation and design of thermo-fluid systems that are innovative inthe energy conversion and energy utilization processes. In addition to conventional energy conversion and propulsionsystems, Prof. You is also interested in renewable and sustainable energy conversion systems such as thin-film solar cellsand wind- and hydro-turbines for electricity and/or hydrogen production and hydrogen conversion systems such ascombustors and fuel cells.

For innovative energy utilization, Prof. You is interested in developing flow control and optimization methods especially forenhancing energy efficiency, performance, and stability, and reducing pollutants, acoustic noise, and other unfavorablefeatures of (i) energy conversion systems (solar cell, fuel cell, and flow battery) and propulsion systems (combustor,compressor, propeller, and turbine); (ii) aircraft high-lift systems and wind turbine blades; and (iii) micro-scale thermo-fluidsystems (applications of hydrophobic surfaces and synthetic jets). Recently, Prof. You extends the computational capabilitiesto discover bio-fluid dynamics in red-blood cell rheology and cardiac flow.

Prof. You and his research team are approaching the research goal with the work focusing on the following areas:

● Computational Flow Physics and EngineeringDevelopment and utilization of new subgrid-scale models (e.g.,global-coefficient eddy-viscosity model) and advanced

numerical methods (geometrically-flexible, accurate, and stable methods based on discrete conservation principles) for large-eddy simulation of turbulent flows in complex configurations, global-coefficient subgrid-scale model for compressibleturbulence and scalar transport in complex configurations, and grid- independent large-eddy simulation employing explicitfiltering techniques.

● Integrated Multiphysics Simulations Integrated simulation and analysis of multi-physics (turbulence, combustion, spray dynamics, heat transfer, pollutants

formation) in energy conversion /propulsion systems (especially combustors in aircraft jet engines and industrial gas turbineengines) using multiple code (large-eddy simulation, Reynolds-averaged Navier- Stokes simulation, Lagrangian spraydynamics, chemical reaction) coupling techniques. Integrated simulations of fluid-structure interaction, flow-induced noiseand vibration in engineering as well as biological systems.

● Flow Control and Optimization for Energy- and Environment-Compatible Thermo-Fluid Systems Development of efficient flow control and optimization methods for (i) enhancing efficiency and performance and reducing

pollutants and acoustic noise of energy conversion systems (combustor, compressor, propeller, turbine, diffuser); (ii)enhancing performance and stability and reducing noise of high-lift systems (aircraft wing, wind turbine wing); and (iii)enhancing mixing and heat transfer in production of thin-film solar cells and operation of fuel cells, and reducing form/skin-friction drag in micro-scale thermo-fluid systems (hydrophobic surfaces, synthetic jets).

● Renewable and Sustainable Energy Systems

Design, simulation, and analysisof renewable and sustainableenergy conversion systems such asthin-film fuel cells and wind- andhydro- turbines for electricity and/orhydrogen production and hydrogenconversion systems such ascombustors and fuel cells aiming athigh efficiency, performance, anddurability, and low emission andacoustic noise.

Major Publications■ Lee, J. & You, D., 2013, Study of Vortex-Shedding-Induced Vibration of a Flexible Splitter Plate behind a Cylinder. Physics of

Fluids, Vol. 25 (11), 110811.■ Lee, J. & You, D., 2013, An Implicit Ghost-Cell Immersed Boundary Method for Simulations of Moving Body Problems with

Control of Spurious Force Oscillations. Journal of Computational Physics, Vol. 233, pp. 295-314.■ You, D., Ham, F. & Moin, P., 2008, Discrete Conservation Principles in Large-Eddy Simulation with Application to Separation

Control Over an Airfoil. Physics of Fluids, Vol. 20 (10), 101515.■ You, D., Wang, M., Moin, P. & Mittal, R., 2007, Large-Eddy Simulation Analysis of Mechanisms for Viscous Losses in a

Turbomachinery Tip-Clearance Flow. Journal of Fluid Mechanics, Vol. 586, pp. 177-204.■ You, D. & Moin, P., 2007, A Dynamic Global-Coefficient Subgrid-Scale Eddy-Viscosity Model for Large-Eddy Simulation in

Complex Geometries, Physics of Fluids, Vol. 19 (6), 065110.

Nanoscale Photonics and Integrated Manufacturing

Jun Suk Rho

Education Ph.D. 2013 University of California,

BerkeleyM.S. 2008 University of Illinois,

Urbana-ChampaignB.S. 2007 Seoul National University

Experience 2014 - Assistant Professor,

POSTECH2013 - 2014

Argonne Scholar - Ugo FanoFellow Argonne National Laboratory

2013 - 2013Postdoctoral FellowLawrence Berkeley NationalLaboratory

2009 - 2013 Affiliate ScientistLawrence Berkeley NationalLaboratory

Contact Tel: +82-54-279-2187Fax: +82-54-279-5899Email: jsrho@postech.ac.kr Homepage:http://photonics.postech.ac.kr

Rho’s research group is not only developing a new concept of novel optical nanomaterials having extraordinary andunprecedented electromagnetic properties based on fundamental physics and experimental studies of deep sub-wavelengthlight-matter interaction, but also realizing engineering device applications including, but not limited to, super-resolutionimaging, negative index materials, tunable high refractive index metasurface, nanoscale laser and next generation scalablenanomanufacturing methods.

Prof. Rho has authored and co-authored high impact journal papers including Science, Nature Photonics and NatureCommunications. His work has been introduced and widely covered by media such as IEEE Spectrum, LBL News, ScienceDaily, Physics World, Photonics Spectra, YTN News, Korea Times, Korea Economic Daily and Seoul Economic Daily. He isalso the recipients of notable honors and awards in the field such as MRS student award, SPIE scholarship, SamsungFellowship and DOE Argonne Named Fellowship.

Specific area and research direction are as below:

Metamaterials Metamaterials, artificially structured nanomaterials, have enabled the extraordinary optical properties andunprecedented phenomena such as invisibility cloaking and negative refraction. We are designing and conductingexperimental realization of novel negative index metamaterials, chiral metamaterials, hyperbolic metamaterials andmetasurface working with low loss and broad bandwidth.

Plasmonics Due to plasmonic mode excitation of high-k vector access in dispersion relation, light can be confined to deepsub-wavelength. We are not only investigating the energy transportation mechanisms and applications at nanometer lengthscale, but also studying plasmon (electron)-polariton (phonon) interaction for non-linear properties of light.

Device Applications With the properties of unnaturally high wavevectors access, super-resolution hyperlens imaging beyonddiffraction limit has been demonstrated from our group. Its extraordinary performances such as super-resolution, real-timeand non-vacuum working environment open a new possibility for nanoscale biological imaging, which can be very practical.Such efforts to make more practical metadevices are being pursued.

Nanofabrication and Nanomanufacturing Along with novel nanofabrication method development, experimentaldemonstration and applications of scalable nanomanufacutring research is actively ongoing. It includes, but not limitedto, hyperlens based 2D lithography and 3D printing (sub-50nm), flying head maskless flying head nanolithography (sub-22nm), single quantum dot patterning (sub-15nm) and nanocascade patterning (sub-10nm) and other unconventionalnanofabrication/manufacturing approaches.

Major Publications■ K. O’Brien and J Rho et al., “Predicting nonlinear properties of metamaterials from the linear response”,

Nature Materials 2014 (in press)■ K. O’Brien and J Rho et al., “Ultrafast acousto-plasmonic control and sensing in complex nanostructures”,

Nature Communications 5, 4042, 2014■ X. Yin and J. Rho et al., “Anomalous photonic spin-hall effect at metasurface”, Science 339, 1405-1407, 2013■ S. Zhang and J. Rho et al., “Photo-induced handedness switching in terahertz chiral meta-molecules”,

Nature Communications 3, 942, 2012■ J. Rho et al., “Experimental realization of 3D indefinite cavities at the nanoscale with anomalous scaling law”,

Nature Photonics 6, 450-454, 2012