Intro to aerodynamics

1. Introductions
Lecture: 1

2. AERO-213 : Incompressible Aerodynamics
Aerodynamics as a Subject
• Study of the behavior of air as it interacts with objects in motion.
• Sub-branch of Fluid Mechanics
– Study of all fluids under static and dynamic situations
Incompressible
Aerodynamics
Fluid Mechanics
Airfoil / flow
Theories
Part 1: Fundamentals of Fluid
Mechanics
• Introduction to Fluid
Mechanics and
Incompressible Flows.
• Analysis of fluid flows, mass
flow rates, forces, and energy
flux.
• Study of elementary flows and
their superposition.
Part 2: Incompressible
Aerodynamics and Airfoil
Theory
• Incompressible Aerodynamics,
Airfoils, and lift and drag.
• Airfoil / lifting line theories.
• Exploration of lift and drag
characteristics for practical
applications.

3. AERO-213 : Incompressible Aerodynamics
Objective of the Course
S No CLO Statement
1
Understand and derive governing equations of fluid flow and identify tools for basic
understanding for incompressible and irrotational Flows
2 Analyze inviscid flow using elementary flows and its superposition.
3 Analyze the aerodynamics of 2-D Aerofoil and wing using potential flow theory.

4. AERO-213 : Incompressible Aerodynamics
Fundamentals of Aerodynamics
by John D. Anderson
Description
• Widely regarded as a classic and authoritative textbook in the field of
aerodynamics.
• Used as a cornerstone resource by aerospace engineering students and
professionals worldwide.
• Comprehensive coverage of key aerodynamic concepts and principles.
• Numerous real-world examples and applications to enhance understanding.
• Valuable exercises and problems for hands-on learning and practice.
• A trusted reference for anyone passionate about flight and aerospace
engineering.

5. AERO-213 : Incompressible Aerodynamics
• Grading Based on:
Quizzes 10-15%
Assignments 5-10%
OHTs 30-40%
ESE 40-50%

6. • Applications in Automobile and Locomotives

7. • Applications in Medical Science
Blood flow through arties
Application in design of Blood pump
Airflow through Lungs

8. • Applications in Household
Flue Baffle use in Geysers
Thermosiphon effect in Solar Geyser
Use of CFD for HVAC design
Atomizer Tap design

9. • Applications in Civil Engineering
Transport of sediments in Dams
Movement of Sediments
Prediction of wind loads on buildings

13. Chapter-1
Fundamental Concepts
AERO-213 : Incompressible Aerodynamics

14. What is a Fluid Mechanics?

15. Today’s Lecture
 What is a Fluid?
 Types of Flows
 Continuum versus Free Molecular Flow
 Inviscid versus Viscous Flow
 Incompressible versus Compressible Flow

16. What is a Fluid?
 A substance that continually deforms (flows) under an applied shear stress regardless of the magnitude
of the applied stress. Whereas a solid can resist an applied force by static deformation.
 Liquids, gases, plasmas and, to some extent, plastic solids are accepted to be fluids.
 Liquids form a free surface (that is, a surface not created by their container) whereas gases
and plasmas do not, but, instead, they expand and occupy the entire volume of the container

17. Fluid as a Continuum
• Fluid as a Continuum: Views fluids as continuous substances without empty
spaces or gaps between particles.
• No Empty Spaces: According to this hypothesis, there are no gaps or voids
between individual fluid particles.
• Mean Free Path: The average distance between particle collisions in a fluid.
• Knudsen Number: Compares the mean free path to the flow length scale.
If λ is small compared to representative physical length: Continuum
If λ is com[parable to representative physical length: Not Continuum

18. Fluid Flow under shear Stress
 A substance that continually deforms (flows) under an applied shear stress regardless of the magnitude
of the applied stress.
 Depending upon the medium, shear stress may cause a change in fluid flow between layers

19. Fluid Flow under shear Stress
 A substance that continually deforms (flows) under an applied shear stress regardless of the magnitude
of the applied stress.
 Depending upon the medium, shear stress may cause a change in fluid flow between layers
 relationship between shear stress and the shear rate is illustrated

20. Newtonian vs Non-Newtonian Fluids
Newtonian Fluids:
• Viscous stresses (Shear Stress)
is linearly correlated to the local
strain rate

21. Newtonian vs Non-Newtonian Fluids
Viscosity
• Fluid property only manifested during
flow
• A measure of its resistance to
deformation at a given rate.
• Viscosity quantifies the internal
frictional force between adjacent
layers of fluid that are in relative
motion
• Depends on fluid and flow conditions

22. Newtonian vs Non-Newtonian Fluids
Non-Newtonian Fluids
• Shear stress and strain rate are
not linear
Apparent viscosity

23. Inviscid versus Viscous Flow
• In fluid dynamics, inviscid flow is the flow of an inviscid (zero-
viscosity) fluid, also known as a superfluid / idealfluid
• In viscous flow, the velocity at the surface of the body will be zero.
• This approximation simplifies analysis

24. NO-SLIP CONDITION
• The speed of the fluid layer in direct contact with the boundary is
identical to the velocity of this boundary
REMEMBER FOR LIFE!!

25. Incompressible versus Compressible Flow
• A compressible fluid can experience a density change during flow
while an incompressible fluid does not experience such a change
• Bulk Modulus (E): ratio of the infinitesimal pressure increase to
the resulting relative decrease of the volume.

26. Incompressible versus Compressible Flow
• A compressible fluid can experience a density change during flow
while an incompressible fluid does not experience such a change
• Mach Number is the measure of the importance of density
changes for compressible flows

27. QUESTIONS??