Solution to Homework #5
1. Problem #1 in Topic 4.
Two circular tubes of identical length are connected to the same liquid reservoir in which a
power-law fluid is held. The tubes differ in radii by a factor of 2. When a pressure drop P
is imposed, the volu

PTFE3230: POLYMER/FIBER PROCESSING
EXAM #3 SPRING 2009
Total time allocated: 120 minutes
Student Name: _
PTFE 3230: Exam #3, Spring 2009 (Close Book & Notes)
Page 1 of 8
Part I: Multiple-Choice Questions (total 2 20 = 40 pts)
1. Which of the following is

Solution to Homework #2
T
T
1. Using Einstein notation, show that the tensor A + A is symmetric, and the tensor A A is
antisymmetric.
Solution:
T
A symmetric tensor B satisfies B = B
(
T
T
A + A = Aij eij + A ji eij = ( Aij + A ji )eij while A + A
) = ( A

Solution to Homework #3, PTFE3230, spring 2012
1.
Consider uniaxial extension with tensile stress f = 10 Pa acting on one end of a tensile bar.
Find the shear stress on the plane slanted at 30 to the base as shown in the figure below.
n t
f
30
Solution:
1

Solution to Homework #4
1. (From the midterm exam, Spring 2006)
If the power-law viscosity model is used to fit the following viscosity data, what are m and n equal to?
1000
100
10
(Pa-s)
1
0.1
0.01
0.001
0.0001
1.0E+00
1.0E+02
1.0E+04
1.0E+06
1.0E+08
1.

Solution to Homework #6
0 & 0
1. Consider an interface deformed in simple shear with a velocity gradient of L = 0 0 0 .
0 0 0
The initial interface has an area of A0 and a unit normal of n 0 . Write the interfacial area A
as a function of time t in ter

Solution to Homework #7
PTFE 3230: Polymer/Fiber Processing
Spring 2012
Problem #1
For the solid conveying zone of an extruder as shown in the following figure, some
design and process parameters are given:
Ds = Db = 60 mm (the clearance between screw and