Math 215

Continuum-Molecular Modeling and Simulation

Class meets Mo,We,Fr, 11:00-11:50 AM, Phillips 303, Fall Semester, 2004
Instructor: Sorin Mitran
Office hours: Mo,We,Fr, 10:00-10:50 AM, Phillips 307

[Motivation] [Syllabus] [Grading] [Texts] [Homework] [Projects] [Mid-term] [Final]

Motivation and objectives

Typically physics furnishes the equations and boundary conditions describing the bulk behavior of matter. Mathematics then attempts to ascertain the existence of solutions and devise practical means to find these solutions. A great deal of success has traditionally been achieved in the sciences through this approach. The equations of fluid dynamics, elasticity, electrodynamics have all been linked to specific microscopic descriptions of matter. These equations have been studied and many methods have been found to find exact or approximate solutions. Yet, when we look at the materials encountered in our immediate surroundings we immediately find cases where the classical continuum level descriptions break down or are invalid. Complex fluids, solids with imperfections in their crystalline structure, plastic materials - all of these are outside the realm of the classical studies. The basic issue that arises again and again is that we do not know how to analytically pass from a realistic microscopic model of the material to a continuum level description. We shall investigate this issue in depth. First, we review some basic cases from classical physics to introduce the methods traditionally used to derive a continuum description from a molecular model. Then we shall present the basic difficulties faced in materials with complicated microscopic behavior. Finally we shall concentrate on computational approaches to solving these difficulties considering a number of practical situations.

Syllabus

  • Elementary kinetic theory

  • Basic statistical physics

  • Constitutive laws

  • Specific models: solid rupture, plastic materials, polymer flows, biological systems

Grading Policy

Grading is based upon homework (20 points), midterm (10 points) and final (10 points) examinations and a final project (60 points). The homework is intended to verify comprehension of simple concepts. Each assignment shall contain 4 questions worth 0.5 grade points each. The weekly homework should require no more than 30 minutes to complete. The midterm and final examinations are given in the same vein - a simple verification of basic concepts. The projects form the most extensive coursework and shall require background research, numerical simulation and the drafting of a report. Grade points are translated to letter grades according to the following table:

Clear Excellence

H

81-100 points

Entirely Satisfactory

P

66-80 points

Low Passing

L

40-65 points

Failed

F

0-39 points

Course Texts

Lecture notes will be distributed periodically through this web site. The following texts are useful for background and more in depth discussions of the course material:

Statistical Physics: Berkeley Physics Course, Vol. 5 (McGraw Hill) by F. Reif, 1967

Statistical Physics by L. Landau and D. Lifschitz, (Oxford) 1967

Kinetic theory : classical, quantum, and relativistic descriptions, by Richard Liboff, (Prentice Hall)

Thermodynamics and Thermostatistics, Herbert Callen, 1985, Prentice Hall.

Thermodynamics and Statistical Mechanics, W. Greiner, L. Heise, H. Stöcker, 1995, Springer

A survey paper on multiscale computation by Achi Brandt: Multiscale Scientific Computation

Technical reports from the Gauss Multiscale Computation Center of the Weizmann Institute

SIAM Journal: Multiscale Modeling and Simulation

Lecture notes

Lecture
Date

Topic

Notes

Lecture
Date

Topic

Notes

1, 8/25

A simple model of a string

Lect01.pdf

 

2, 8/27

String rupture, C-M issues

Lect02.pdf

3, 8/30

Dilute polymer flows

Lect03.pdf 

4, 9/1

Biological systems

Lect04.pdf

5, 9/3

Boltzmann equation

Lect05.pdf 

 9/8

Homework review

 

6, 9/10

Conservation equations

Lect06.pdf 

7, 9/13

Maxwell-Boltzmann distribution

Lect07.pdf

 

 

8, 9/15

Chapman-Enskog expansion

Lect08.pdf

9, 9/17

Analytical mechanics primer

Lect09.pdf 

10, 9/20

Liouville equation

Lect10.pdf 

11, 9/22

BBGKY hierarchy

Lect11.pdf 

 

9/24

Project ideas

 

12, 9/27

Thermodynamics

Lect12.pdf

13, 9/29

Ideal gas, TD potentials

Lect13.pdf

14,10/1

Statistical mechanics

Lect14.pdf

15, 10/4

Multiscale computation

 

 

 

Homework

Homework is given each Friday and due the next Friday. Solutions are posted at the end of the Due Date. Please download the homework from the website.

HW #

Due

Problems

Solution

HW #

Due

Problems

Solution

1

9/3

HW01.pdf

6

10/22

2

9/10

HW02.pdf

7

10/29

3

9/17

HW03.pdf

8

11/5

4

9/24

HW04.pdf

9

11/12

5

10/1

HW05.pdf

10

11/19

 

Projects

Fracture mechanics

Shell failure under dynamic bending - model project

Shell failure under traction - model project

Viscoelastic flow

Mucus layer flow - Brandon Lindley

Dilute polymer flow in a soap film -

Nematic polymer films - Joohee Lee

Biology

Fungus growth - Eric Choate

Subdiffusion

Diffusion through tangled polymers - Zhi Lin

Diffusion through regular lattices - Lingxing Yao

Contact Lines

Inmiscible fluids in porous media - James McClure

Merging of contact lines - Xiaoyu Zheng

Droplets

Acoustic excitation and breakdown - model project