A brief history of fluid mechanics

1. 1

2. History of Fluid Mechanics
Invented scientists Concept Pictorial representation
Sailing ships with
oars and irrigation
systems (Prehistoric
period)
Ancient civilizations
Concept of flow
problems
Source:
https://www.freepik.com/pre
mium-vector/vintage-sailing-
ship-drawing_17744860.htm
Archimedes
Source:
https://www.britannica.co
m/biography/Archimedes
Alexandria
Third Century B.C
Parallelogram law
of vector addition
2

3. Invented scientists Concept Pictorial
representation
Archimedes
(285-212 B.C)
Source:
https://www.mecholic.co
m/2018/06/conditions-
of-equilibrium-of-
floating.html
Leonardo da vinci
(1452-1519)
Source:
https://www.leonardodavinci.net/
Description of
waves, jets,
hydraulic jumps,
eddy formation,
streamlined and
parachute designs
Source: Vortex studies in
currents (Windsor Castle,
The Royal Collection, RL
1266ov)
Edme Mariotte
(1620-1684)
Source:
https://en.wikipedia.org/wiki/Edm
e_Mariotte
Built and tested the first Wind tunnel
History of Fluid Mechanics
Laws of buoyancy
for floating and
submerged bodies
3

4. History of Fluid Mechanics
Sir Isaac Newton
(1642-1727)
Source:
https://en.wikipedia.org/wiki/Is
aac_Newton
Law of motion and
law of viscosity of the
linear fluid
Leonhard Euler,
Daniel Bernoulli, Jean
D’Alembert, Joseph-
Louis Lagrange and
Pierre-Simon Laplace
Solution of Friction – flow problem by
differential equation of motion and their
integral form
D’Alembertz
(1717-1783)
Source:
https://en.wikipedia.org/wi
ki/Jean_le_Rond_d%27Ale
mbert
The body immersed in a frictionless fluid
has zero drag
4

5. History of Fluid Mechanics
Chezy, Pitot, Borda,
Weber, Francis,
Hagen, Poiseuille,
Darcy, Manning,
Bazin and
Weisbach
Produced data on
variety of laws such
as open channels,
ship resistance, pipe
flows, waves, and
turbines
Fundamental
physics of flow
William Froude
(1810-1879)
&
Robert Edmund
Froude
(1846-1924)
Law of model testing
Lord Rayleigh
(1842–1919)
Dimensional Analysis
Osborne Reynolds
(1842–1912)
Fluid dynamics
Concept
Source: https://www.simscale.com/docs/simwiki/numerics-
background/what-is-the-reynolds-number/ 5

6. History of Fluid Mechanics
Navior
(1785-1836)
&
Stokes
(1819-1903)
Fluid motion governing equation
including viscous term
Ludwig Prandtl
(1875–1953)
Fluid flows with small viscosity
6

7. Dimensions and Units
Fundamental
Dimension
SI Unit BG Unit Conversion factor
Mass (M) Kilogram (kg) Slug 1 slug = 14.5939 kg
Length (L) Meter (m) Foot (ft) 1 ft = 0.3048 m
Time (T) Second (s) Second (s) 1 s = 1 s
Temperature
(ϴ)
Kelvin (K) Rankine (⁰R) 1 K = 1.8 ⁰R
SI = International System of Units
BG = British Gravitational Units
Derived Dimension in Fluid Mechanics
Derived Dimension SI BG Conversion factor
Area (L2) m2 ft2 1 m2 = 10.764 ft2
Volume (L3) m3 ft3 1 m3 = 35.315 ft3
Velocity (LT-1) m/s ft/s 1 ft/s = 0.3048 m/s
Acceleration (LT-2) m/s2 ft/s2 1 ft/s2 = 0.3048 m/s2
Pressure or Stress
(ML-1T-1)
N/m2 lbf/ft2 lbf/ft2 = 47.88 Pa
Angular velocity (T-1) s-1 s-1 1 s-1 = 1 s-1
Energy, Heat, work
(ML2T-2)
Nm (J) ft.lbf 1 ft.lbf = 1.3558 J
Density (ML-3) kg/m3 slugs/ft3 1slugs/ft3 = 515.4 kg/m3
Viscosity (ML-1T-1) kg.s/m slugs/ft.s 1 slugs/ft.s = 47.88 kg.s/m
Power (ML2T-3) J/s (W) ft.lbf/s 1 ft.lbf/s =1.3558 W
Fundamental Dimension in Fluid Mechanics
7

8. Prefixes for Engineering Units
Multiplicative
factor
Prefix Symbol
1012 tera T
109 giga G
106 mega M
103 kilo k
102 hecto h
10 deka da
10-1 deci d
10-2 centi c
10-3 milli m
10-6 micro µ
10-9 nano n
10-12 pico p
10-15 femto f
10-18 atto a
8

9. Dimensional Homogeneity
In engineering and science, all equations
must be dimensionally homogeneous, each
additive term in an equation have the same
dimensions.
Example 1 : Velocity measurement by pitot
tube
1
1
2
1
2
2
2


















LT
gH
of
Dimension
V
of
Dimension
LT
L
T
L
gH
of
Dimension
LT
T
L
V
Velocity
of
Dimension
gH
V
Example 2 : Bernoulli’s Incompressible
Equation
Each term has same dimension (ML-1T-2 )
constant
2
2
1


 gZ
V
p 

9

10. Branches of Fluid Mechanics
Fluid
Mechanics
Hydrostatics
Study of fluids at rest
or flow with constant
velocity
Kinematics
Study of the geometry
of fluid motion
Fluid
Dynamics
Study of the forces that
cause accelerated
motion
10
Reference
1. Yunus A. Cengel ; John M. Cimbala, Fluid Mechanics,
McGraw Hill Education Pvt. Ltd.,2014
2. R.C. Hibbler, Fluid Mechanics, Pearson Publishing
Education Ltd., 2022