ppt

1. UNIT I
PROPERTIES OF FLUIDS

2. UNIT I PROPERTIES OF FLUIDS
Properties of fluids- definition -units of
measurement - Measurement of pressure by
various types of manometers - Hydrostatic
forces on surfaces -total pressure and center
of pressure - Horizontalvertical and inclined
plane surface - Archimedes principles -
buoyancy - metacenter -metacentric height

3. Pressure
 Pressure is defined as force per unit area.

5. Fluid Pressure:
 When a certain mass of fluids is held in static equilibrium by confining
it within solid boundaries, it exerts force along direction
perpendicular to the boundary in contact.

6. Pressure Distribution:
 There are two types of pressure distribution.
a) Uniform Pressure distribution.
b) Non-Uniform Pressure distribution.

7. Pressure at a point
 p = dF/dA
 p = F/A
 p – intensity of pressure or pressure
Units:
N/m2 = Pa
 1MPa = 1 N/mm2
 1Gpa = 10*3 N/m2
 1bar = 10*5 N/m2
 1 atm = 101.3 kPa = 760 mm of Hg = 10.33 m of
water

8. Pressure Measurement:
 The pressure of a fluid is measured by the following device
a) Manometer
b) Mechanical gauges

9. Manometer

12. Types of Manometers
1. Simple manometers
a. Piezometer
b. U-Tube
c. Single column/Micro Manometer
- vertical Single column Manometer
- Inclined Single column Manometer
 2. Differential manometers
a. U-Tube Differential manometers
b. Inverted U-Tube Differential manometers

13. Mechanical Gauges:
Types commonly used are:
a) Diaphragm pressure gauge
b) Bourdon tube pressure gauge
c) Dead weight pressure gauge
d) Bellows pressure gauge

14. Variation of Pressure in a Static Fluid
Hydrostatic Law : “ The rate increase of
pressure in a vertically downward direction
must be equal to specific weight of the fluid
at that point ”

15. EXPRESSING PRESSURE
Atmospheric
Gauge
Vacuum
Absolute

16. Relationships
a. Absolute pressure= Atm pr + Gauge pr
Pab = Patm + Pgauge
b. Vacuum pressure= Atm pr – Absolute pr

17. Types of Manometers
1. Simple manometers
a. Piezometer
b. U-Tube
c. Single column/Micro Manometer
- vertical Single column Manometer
- Inclined Single column manometer

18. Types of Manometers
1. Simple manometers
a. Piezometer
b. U-Tube
c. Single column/Micro Manometer
- vertical Single column Manometer
- Inclined Single column Manometer
 2. Differential manometers
a. U-Tube Differential manometers
b. Inverted U-Tube Differential manometers

19. 1. Simple manometers
A simple manometer is one which consists of a
glass tube, whose one end is connected to a point
where pressure is to be measured and the other end
is open to atmosphere.

20. a) Piezometer:
The pressure at point A is given by
p = w*h, where w is the specific
weight of the liquid
i.e., P= ρgh (N/m²)
i.e Specific weight(ρg) * pr height
(h)

21. U – Tube Manometer:

22. b) U – Tube Manometer:
 The "U" is connected as in the figure and filled with a fluid called the
manometric fluid.

24. For gauge pressure (fig a)
Pressure above A-A in left column
= p + ρ1gh1------(1)
Pressure above A-A in right limb
= ρ2gh2------ (2)
p= (ρ2gh2 – ρ1gh1) (N/m²)

25. For vacuum pressure (fig b)
Pressure above A-A in left column
= ρ2gh2 + ρ1gh1+p-----(1)
Pressure above A-A in right limb
= 0 ------- (2)
p= -(ρ2gh2 + ρ1gh1) (N/m²)

26. Differential manometers
a. U-Tube Differential manometers
b. Inverted U-Tube Differential manometers
• Differential manometers

27. a) U-tube Differential manometers
It is used to measure pressure difference at
two points in a pipe or between two pipes at
different levels.

28. b) Inverted U-tube Differential manometers