Fluid Mechanics

Fluid

anything that flows; liquid and gas

What is Pressure caused by

the weight of the column of fluid above that point + pressure acting on the surface of that column

Absolute Pressure

the difference between the measured pressure and a vacuum

Gauge Pressure

the difference between measure pressure and atmospheric pressure

Eureka

states that the buouant force on a submerged object is based upon the weight of the displaced fluid

Definition of Pressure
P = F/A

F = force in Newtons
A = surface area in m2

Density
roe = m/V

V = volume in m3
m = mass in kg

Pressure in a Static Column of Fluid (at any point in the fluid)
P = P0 + (roe)gh

P = pressure in pascals
P0 = pressure acting on surface of the fluid
roe = density in kg/m3
g = acceleration due to gravity
h = height of the column of fluid above the point where pressure is being determined

Buoyancy Force
Fb = (roe)Vg

roe = density of displaced fluid in kg/m3
V = volume of displaced fluid in m3

Continuity Equations
A1v1 = A2v2
V/T = Av
m/t = (roe)Av

A = cross sectional area of pipe or flow tube in m2
v = fluid velocity in m/s
V/t = volumetric flow rate in m3/s
m/t = mass flow rate in kg/s
roe = density of fluid in kg/m3

Bernoulli's Equation
P1 + (roe)gy1 + 1/2 (roe)v12 = P2 + (roe)gy2 + 1/2 (roe) v22

y = the height of a position in a column of fluid in meters

Equilibrium

all forces are canceling out

The forces cause by fluid pressure will always be parallel/perpendicular to the surface the fluid is in contact with

perpendicular

1gm/cm3 = ?

1000kg/m3

density of water

1000kg/m3

weight of a fluid can be written as...

(roe)Vg

1Pa =?

1N/m2

Pabsolute =?

Pgauge + 100000 Pa

Does the shape of the container affect pressure for a static fluid

no