Microfluidics

Overview

Introduction:Origin, Definition, Benefits, Challenges, Commercial activities, Physics of miniaturization, Scaling laws;Micro-scale fluid mechanics:Intermolecular forces, States of matter, Continuum assumption, Governing equations, Constitutive relations - Gas and liquid flows, Boundary conditions, Slip theory, Transition to turbulence, Low Re flows, Entrance effects - Exact solutions, Couette flow, Poiseuille flow, Stokes drag on a sphere, Time-dependent flows, Two-phase flows, Thermal transfer in microchannels - Hydraulic resistance and Circuit analysis, Straight channel of different cross-sections, Channels in series and parallel;Capillary flows:Surface tension and interfacial energy, Young-Laplace equation, Contact angle, Capillary length and capillary rise, Interfacial boundary conditions, Marangoni effect;Electrokinetics:Electrohydrodynamics fundamentals - Electro-osmosis, Debye layer, Thin EDL limit, Ideal electro-osmotic flow, Ideal EOF with back pressure, Cascade electro-osmotic micropump, EOF of power-law fluids - Electrophoresis of particles, Electrophoretic mobility, Electrophoretic velocity dependence on particle size - Dielectrophoresis, Induced polarization and DEP , Point dipole in a dielectric fluid, DEP force on a dielectric sphere, DEP particle trapping, AC DEP force on a dielectric sphere - Electro-capillary effects, Continuous electro-wetting, Direct electro-wetting, Electro-wetting on dielectric.

Microfabrication techniques:Materials, Clean room, Silicon crystallography, Miller indices - Oxidation, photolithography- mask, spin coating, exposure and development, Etching, Bulk and Surface micromachining, Wafer bonding - Polymer microfabrication, PMMA/COC/PDMS substrates, micromolding, hot embossing, fluidic interconnections - Microfluidics components:Micropumps, Check-valve pumps, Valve-less pumps, Peristaltic pumps, Rotary pumps, Centrifugal pumps, Ultrasonic pump, EHD pump, MHD pumps - Microvalves, Pneumatic valves, Thermopneumatic valves, Thermomechanical valves, Piezoelectric valves, Electrostatic valves, Electromagnetic valves, Capillary force valves - Microflow sensors, Differential pressure flow sensors, Drag force flow sensors, Lift force flow sensors, Coriolis flow sensors, Thermal flow sensors - Micromixers, Physics of mixing, Pe-Re diagram of micromixers, Parallel lamination, Sequential lamination, Taylor-Aris dispersion - Droplet generators, Kinetics of a droplet, Dynamics of a droplet, In-channel dispensers, T-junction and Cross-junction, Droplet formation, breakup and transport - Microparticle separator, principles of separation and sorting of microparticles, design and applications - Microreactors, Design considerations, Liquid-phase reactors, PCR, Design consideration for PCR reactors;Few applications of microfluidics:Drug delivery, Diagnostics, Bio-sensing