두개이상의상이한유체의상호교감 (Mutual Response of Liquid Droplets and their Non-linear Dynamics) Joon Sang Lee Mechanical Engineering, Yonsei University, Seoul, Korea. joonlee@yonsei.ac.kr 2013/12/18
1 Contents Contents 인간의삶과자연의유사성 상호교감융복합연구센터 유체의상호교감 연구분야 현재연구수준 맺음말
1 인간의삶과자연의유사성 Individual + individual Family Individual + individual + Interaction = Family
1 인간의삶과자연의유사성 Molecule + Molecule Liquid Molecule + Molecule + Interaction = Liquid
2 상호교감융복합연구센터 Various Environment Interaction Research Center (VEIReC) 설립배경지난 10 여년간새로운개념과가치를창출하기위해 Information Technology, Bio Technology, Nano Technology, Environment Technology 등으로분류되는기술간의교류가활발하게진행되었다. 본연구센터는세계적인수준의기술을활용하여인간의삶을이루는각요소들간의상호작용에대한보다본질적인이해를구하고, 이를바탕으로인류발전에이바지할수있는진정한의미에서의차세대융합기술을개발하는것에최종목표를두고있다. 연구내용 Wellness Tech. 감성은정치, 사회, 교육, 의료등다양한분야에서발생하는문제해결의키워드로부상하면서사람들의관심을받고있다. 간편하고경제적인방법을통해서개인의감정상태를점검하고측정할수있다면, 감성의이상적변화나상태에대한객관적해석이가능하며, 이를통해사회적 / 심리적인갈등을해소할수있는방안을강구할수있다. Health Tech. 의학기술의발달은의사의손에의존하는치료범위를넘어서면서점차적으로공학적인기술및미래지향적인문학을요하게되었다. 특히암이나뇌졸중등불치병으로치부되었던질환들에대한해결방안이모색되면서이를해결하기위한다양한의학기기들이개발되고있는추세이고장기적인계획이가능하다. Environmental Tech. 대체에너지기술개발이나오염물질포집기술, 또는시뮬레이션을통한기상예측등최첨단공학기술들의도움으로보다효율적이고친환경적인사회를구축할수는있으나이에따른주변환경과의상호작용에따른긍정적 / 부정적인측면도개발성과에포함되어야한다. Social Communication 전세계의기상을쉽게일반인들에게보여줌으로써지구온난화등의보편적인환경에관심을가지게하거나클라우드컴퓨팅을이용하여수많은의료정보를일반인들도쉽게공유할수있게하는등의기술은실제로현재개발중이다. 이를통해보다더쉽게상호융합적인인터페이스를개발하고활용할수있는길을제안할수있다.
3 유체의상호교감 Coalescence is the process by which two or more droplets, bubbles or particles merge during contact to form a single daughter droplet, bubble or particle. It can take place in many processes, ranging from meteorology to astrophysics. For example, it is seen in the formation of raindrops as well as planetary and star formation.
3 유체의상호교감 Two mechanisms for suppressing coalescence are presented here. (A) Surfactant concentration gradient. (B) Steric repulsion (Lyu et al., 2002). Illustration of the domain for the simple shear flow used to calculate effective viscosity Liu and Liu (2006).
3 유체의상호교감
4 연구분야 Emulsion : A mixture of two or more liquids that are normally immiscible Emulsion = Liquid + Liquid = Liquid or Solid? Liquid Solid Character 흐른다유지한다 Energy Energy dissipation Energy storage Property viscosity 얼마나에너지를잘소산하는가? Elasticity 얼마나에너지를잘저장하는가? Emulsion = Liquid + Liquid = Liquid + Solid
4 연구분야 Where does the solid property(elasticity) come from? An interface is a surface forming a common boundary among two different phases of matter, such as an insoluble solid and a liquid, two immiscible liquids, a liquid and an i nsoluble gas or a liquid and vacuum. E interface > E bulk Solid property (Elasticity) -> Energy storage ability Increase of interfacial area = Increase of E in emulsion system Thus, the solid property of emulsion is come from interface.
4 연구분야 Albert et al. (2002) MODELING APPROACHES One is based on the idea that the changing rigidity of the membrane is a function of the cytoskeleton constituent proteins remodeling, and therefore treat the spectrin chain as springs with bending and shearing elasticity. (Solid problem approach). The other is based on the idea that the lipid bilayer is the major contributor to the RBC shape and deformability, due to its interaction with surface active substances contained in the surrounding plasma. The change in the lipid bilayer causes a change in the surface tension and the energetic balance between the attractive and repulsive interactions of the RBC membrane. (Liquid/droplet problem approach)
4 연구분야
4 연구분야
5 현재연구수준
5 현재연구수준 The effects of surfactants on the droplet behavior
5 현재연구수준 Aggregational characteristics of emulsions. - Numerical measurement of Viscosity Liu and Liu (2007)
5 현재연구수준 Aggregational characteristics of emulsions. Shear rate 3s 1 Peeling effect High shear stress at the contact point between droplet Kondaraju et al. (2012)
5 현재연구수준 Aggregational characteristics of emulsions.
5 현재연구수준 Aggregational characteristics of emulsions.
5 현재연구수준 Aggregational characteristics of emulsions.
5 현재연구수준 Aggregational characteristics of emulsions.
THANK YOU FOR LISTENING. Various Environment Interaction Research Center (VEIReC) CONTACT US For more information please visit our website : http://web.yonsei.ac.kr/fluid E-MAIL joonlee@yonsei.ac.kr