3155/6.,152] Lecture22 Fluids Lab Testing Prof martin a schmidt Massachusetts Institute of Technology 12/1/2003
3.155J/6.152J Lecture 22: Fluids Lab Testing Prof. Martin A. Schmidt Massachusetts Institute of Technology 12/1/2003
Information a quiz Wednesday dec 3, in-class Closed Book Covers materials in lectures from 10/ 15 through 11/26 Does not include lab lectures A formula sheet will be provided (if needed) Lecture on Monday dec. 8th Lab tour of analog devices MEMS Facility We will leave from the classroom at 2 3 5PM SHARP Course evaluations at the end of this lecture Fall 2003-MA schmidt 3. 155]6.152]-Lecture 22-Slide 2
Information Quiz Wednesday, Dec. 3, in-class Closed Book Covers materials in lectures from 10/15 through 11/26 Does not include Lab Lectures A formula sheet will be provided (if needed) Lecture on Monday, Dec. 8th Lab tour of Analog Devices MEMS Facility We will leave from the classroom at 2:35PM SHARP Course evaluations at the end of this lecture Fall 2003 – M.A. Schmidt 3.155J/6.152J – Lecture 22 – Slide 2
Outline Review of the process and Testing Fluidics Solution of Navier-Stokes equation Solution of diffusion problem Lab report guidance References Senturia microsystems design Kluwer 6. 021 Web site on microfluidics lab Plummer, chapter 7, p382-384 Fall 2003-MA schmidt 3. 155] 6.152]-Lecture 22-Slide 3
Outline Review of the Process and Testing Fluidics Solution of Navier-Stokes Equation Solution of Diffusion Problem Lab Report Guidance References Senturia, Microsystems Design, Kluwer 6.021 Web Site on Microfluidics Lab Plummer, Chapter 7, p.382-384 Fall 2003 – M.A. Schmidt 3.155J/6.152J – Lecture 22 – Slide 3
Process Flow- Overview Unexposed Si口 5U-8(100 Surface treatment PDMS photolithography PDMS口 UV light Si口 removing elastomer from Si口 master development PDMS囗 seal against glass after plasma treatment and insert tubi ing Si口 master tubing Our process was changed lere Fall 2003-MA schmidt 3. 155J/ 6. 152]-Lecture 22-Slide 4
Process Flow - Overview Si Unexposed SU-8 (100 µm) Surface treatment & casting PDMS photolithography UV light Si mask Si PDMS removing elastomer from master development Si ing “master” here PDMS seal against glass after plasma treatment and insert tub tubing Our process was changed Fall 2003 – M.A. Schmidt 3.155J/6.152J – Lecture 22 – Slide 4
The mixer laminar flow Width =250um, 500 um ↓ outlet depth=100um Inlet Length= 25 mm idth Outlet Length 35 mm inlet 2 Images: Prof. D. Freeman Fall 2003-MA schmidt 31551/6.,152]- Lecture22-side5
The Mixer Width = 250Pm, 500 Pm Depth = 100 Pm Inlet Length = 25 mm Outlet Length = 35 mm Images: Prof. D. Freeman Fall 2003 – M.A. Schmidt 3.155J/6.152J – Lecture 22 – Slide 5
Packaging/Testing OUTPUT RESERVOIR INPUT RESERVOIRS Images: Prof D. Freeman Fall 2003-MA schmidt 3.155] 6.152]-Lecture 22 -Slide 6
Packaging/Testing Images: Prof. D. Freeman Fall 2003 – M.A. Schmidt 3.155J/6.152J – Lecture 22 – Slide 6
Experiment Gravity feed of fluids Requires priming of channel Particles for velocity measurement We will attempt this Dye for diffusion experiments Measurements Particle velocity Diffusion Fall 2003-MA schmidt 3.155J 6. 152]-Lecture 22-Slide 7
Experiment Gravity feed of fluids Requires ‘priming’ of channel Particles for velocity measurement We will attempt this Dye for diffusion experiments Measurements Particle velocity Diffusion Fall 2003 – M.A. Schmidt 3.155J/6.152J – Lecture 22 – Slide 7
Navier-Stokes The navier-Stokes equation for incompressible flow: DU pm Dt nV2U-四P* U = velocity P=pressure(minus gravity body force Pm =fluid density (103 kg/m3 for water) m=viscosity( 10- Pa-s for water Fall 2003-MA schmidt 3. 155]6.152]-Lecture 22-Slide 8
Navier-Stokes The Navier-Stokes equation for incompressible flow: U = velocity P* = pressure (minus gravity body force) Um = fluid density (103 kg/m3 for water) K = viscosity (10-3 Pa-s for water) Fall 2003 – M.A. Schmidt 3.155J/6.152J – Lecture 22 – Slide 8
Poiseuille flow Assume width( w)>> height (h) Neglect entrance effects(L>>h) W X Fall 2003-MA schmidt 3. 155]6.152]-Lecture 22-Slide 9
Poiseuille Flow Assume width (w) >> height (h) Neglect entrance effects (L >> h) h w L y x Fall 2003 – M.A. Schmidt 3.155J/6.152J – Lecture 22 – Slide 9
Simplify to our problem No time dependence a d dt=0 DU Pm Dt =nVU-VP Flow is constant in x direction(and O in z) ressure is only a a2U K function of x Oa A linear pressure drop dP K constant da Fall 2003-Ma schmidt 315516.152- Lecture22-side10
Simplify to our problem No time dependence d/dt = 0 Flow is constant in xdirection (and 0 in z) U = f(y) Pressure is only a function of x A linear pressure drop Fall 2003 – M.A. Schmidt 3.155J/6.152J – Lecture 22 – Slide 10