STUDENT WORKBOOK

JJ308-FLUID

Unit:

Kilo Hekto Deko unit desi centi mili

1 liter = 1000m3

I kg x 9.81 = 1N

1 bar = 105 N/m @ Pa

Unit 1 : Fluid And Properties

1. Define Fluid

2. Compare the characteristics between liquid, gas and solid

a. Liquid

b. Gas

c. Solid

3. Define of pressure

a. Atmospheric

b. Gauge

c. Absolute

d. Vacuum

- The pressure below the atmospheric pressure ( vacuum)

4. Example problem of pressure

a. What is the pressure gauge of air in the cylinder if the atmospheric gauge is

101.3 kN/m2 and absolute pressure is 460 kN/m2.(358.7kN/m2)

b. A Bourdon pressure gauge attached to a boiler located at sea level shows a

reading pressure of 7 bar. If atmospheric pressure is 1.013 bar, what is the

absolute pressure in that boiler (in kN/m2) ?(801 kN/m2)

5. Fluid properties

a. Mass density, ρ is defined as the mass per unit volume.

b. Specific weight, is defined as the weight per unit volume.

c. Specific gravity or relative density, s is the ratio of the weight of the substance to

the weight of an equal volume of water at 4 ºC.

d. Specific volume, v is defined as the reciprocal of mass density. It is used to mean

volume per unit mass.

e. Viscosity

A fluid at rest cannot resist shearing forces but once it is in motion, shearing

forces are set up between layers of fluid moving at different velocities. The

viscosity of the fluid determines the ability of the fluid in resisting these shearing

stresses.

Kinematic viscosity

This ratio is characterized by the kinematic viscosity (Greek letter nu, ν), defined as follows:

Dynamic viscosity, μ

6. Example problems of fluid properties

a. If 5.6 m3 of oil and weights 46000 N ,determine :

i. Mass density ,ρ in unit kg/m3

ii. Specific weight ,ω

iii. Specific gravity of oil , S

(837.33kg/m3,8214.3N/m3,0.837)

b. Get the relative density , density , specific weight and kinematik viscosity

of an oil which are 7.3 m3 in volume , 6500 kg in mass and dynamic

viscosity is10-3Ns/m2

(s=0.89, ρ=890.41kg/m3,ω=8734.92N/m3 ,1.123x10-6m2/s)

c. Determine the specific volume if it mass is 500g and the volume is 400cm3

(8x10-4m3/kg)

d. Given specific weight of fluid is 6.54 N/litter and its mass is 830 g . Calculate

the following in SI unit

i.Volume of fluid

ii.Specific volume of fluid

iii.Density of fluid (1.245x10-3 m3,1.5x10-3/kg,666.67 kg/m3)

e.Volume and mass for oil are 9.2 m3 and 7300 kg

i. Mass density

ii. Relative density

iii. Specific weight (793.4 kg/m3 , 0.793,7.78x103N/m3)

f. If the mass and volume of air 11.5 kg and 650 cm3, calculate:

i. Mass density

ii. Specific weight

iii. Specific volume

iv. Specific gravity for the air

(17692.31 kg/m3,173558.5N/m3 , 5.352x10-5m3/kg)

g. The volume of engine oil is 5.5m3 and the weight is 50 kN determine

i. Density of oil

ii. Specific weight of oil

iii. Specific volume of oil

iv. Specific gravity

(926.7kg/m3,9091N/m3,1.079x10 -3 m3/kg, 0.9267)

h. Determine the mass density , in SI unit if it s mass is 450g and the volume is

9dm3. (50kg/m3)

i. Determine the specific weight ω ( kN/m2) and specific gravity, s of fluid if the

weight is 100N and the volume is 500cm3

( 20kN/m3, 2.039)

j. The volume of a stone is 1.5 x 10-4 m3. If the relative density of the stone is 2.6,

calculate:

i. The density

ii. The specific weight

iii. The specific volume

iv. The weight

v. The mass

( 2600kg/m3 , 25.506kg kN/m3,3.85 x10-4m3/kg, 3.83 N, 0.39 kg)

k. Given the volume of oil is 3 liter and the weight is 20N, determine the specific

volume, relative density and specific weight of oil.

( 1.471 x10-3m3, 0.68,6670N/m3)

l. Specific gravity of a liquid is 0.85. determine

i. Mass density

ii. Specific volume

(850kg/m3,1.176 x 10-3m3/kg)