CBE 30355 - Lecture Notes - Oct. 14, 2025
Announcements
Class notes
Read through pages 182-190 of the notes and view the online narration below. Don't forget to complete the quiz in Canvas!
The main points of the lecture were
Goals:
After this class you should be able to:
- Scale the transport equations to get the Reynolds Lubrication Equation.
- Apply this equation to calculate the forces in simple lubrication flows.
Reading
- The class notes.
- BS&L, chapter 4
Demonstration:
In the lecture we talk about the detachment of a disk from a plane. The reverse of this (and a very similar problem mathematically) is the velocity profile produced by squeezing a fluid between two disks. Here we show via calculation and demonstration that the radius of a Newtonian liquid with constant squeezing force grows such that R^8 is linear in time. As a bonus we also demonstrate what happens when the fluid is a non-Newtonian suspension, yielding fascinating particle migration mechanics and flow instabilities. A paper describing this latter phenomenon is given here.
David.T.Leighton.1@nd.edu