Page 19 - ebook fluid mechanics_finalize

FLUID MECHANICS

1.3 PRESSURE IN FLUID

The basic property of a static fluid is pressure. Pressure is defined as the
amount of surface force exerted by a fluid on any boundary it is in contact with. It

can be written as:

Force
Pr essure =
Area of which the force is applied
F
P =
A

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2
Unit : N/m or Pascal (Pa). Also frequently used is bar, 1 bar = 1 x 10 Pa

F

Figure 1.4 : Pressure acting uniformly in all directions

Fluid
surfaces

Figure 1.5: Direction of fluid pressures on boundaries

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