Standard Flows for Rheology

1
Standard Flows for Rheology

• Lecture Notes 5

2
Introduction

• What are standard flows?
• Why do we need standard flows?
• What are the general characteristics of a
  standard flow?
• What are the different types of standard flows?

3
Simple Shear Flow (SSF)

• Definition
• Velocity profile (Eqn. 4.1)
• SSF in processing (Fig. 4.3)
• SSF in geometries for rheometers (Eqn. 4.4)
• Strain tensor for SSF (Eqns. 4.2-4.10)
• Stress tensor for a Newtonian fluid in SSF (Eqns.
  4.11-4.13)
• Steady SSF (SSSF)/viscometric flow (Fig. 4.6)
• Stress tensor in SSF (Eqn. 4.73)
• Measuring stresses in SSF
• First and second normal stresses in SSF (Eqn.
  4.78-4.79)

4
SSF
Understanding Rheology, Faith A. Morrison, 2001,
Oxford University Press
5
Geometries for SSF
Understanding Rheology, Faith A. Morrison, 2001,
Oxford University Press
6
Simple Shear Flow (SSF)

• Definition
• Velocity profile (Eqn. 4.1)
• SSF in processing (Fig. 4.3)
• SSF in geometries for rheometers (Eqn. 4.4)
• Strain tensor for SSF (Eqns. 4.2-4.10)
• Stress tensor for a Newtonian fluid in SSF (Eqns.
  4.11-4.13)
• Steady SSF (SSSF)/viscometric flow (Fig. 4.6)
• Stress tensor in SSF (Eqn. 4.73)
• Measuring stresses in SSF
• First and second normal stresses in SSF (Eqn.
  4.78-4.79)

7
Simple shear-Free (Elongational) Flows

• Definition
• Types
• Uniaxial elongational flow
• Biaxial stretching flow
• Planar elongational flow

8
Summary of Elongational Flows
9
Various Types of Elongational Flows
Understanding Rheology, Faith A. Morrison, 2001,
Oxford University Press
10
Processes with Elongational Flow
11
Production of Elongational Flows in the Lab using
Rheometers
Understanding Rheology, Faith A. Morrison, 2001,
Oxford University Press
12
Summary of Elongational Flows
13
Stress Measurement for Elongational Flow

• We need to measure