Momentum Transfer

Question 1

For the laminar flow of a fluid in a circular pipe of radius R, the Hagen-Poiseuille equation predict the volumetric flowrate to be proportional to

Answer 1

R^4

Question 2

When the flow is laminar

Answer 2

the pressure drop is proportional to the first power of the velocity.

Question 3

Pipes having diameter 14 inches or more are designated by
their

Answer 3

outside diameter

Question 4

Most commonly used joint in the underground pipe lines is the

Answer 4

sleevejoint

Question 5

Schedule number of a pipe, which is a measure of its wall thickness, is given by

Answer 5

1000 P’/S

Question 6

Water hammer in a pipeline results from the

Answer 6

rapid pressure change due to a rapid change in the rate of flow.

Question 7

Molten soap mass is transported by a _____ pump.

Answer 7

Gear Pump

Question 8

Nominal size of the discharge pipe of a pump is usually______ the nominal size of the inlet pipe.

Answer 8

smaller than

Question 9

Location of vena-contracta in an orificemeter does not depend
upon the

Answer 9

type of orifice

Question 10

High specific speed of a pump implies that, it is a/an ____ pump.

Answer 10

axial flow

Question 11

Fittings used to connect two pipes with different size.

Answer 11

Reducer

CH 10

Question 11

Fittings used to change direction.

Answer 11

Elbows

CH 10

Question 12

Fittings used for branching.

Answer 12

Tee

CH 10

Question 13

Fittings used to connect the same pipe diameter

Answer 13

Union

CH 10

Question 14

Formula used for Laminar and Compressible Fluids

Answer 14

Poiseuille Equation

Question 15

Formula for Compressible Fluids

Answer 15

E6-115

Question 16

Weymouth equation

Answer 16

. 0.008
ƒ = ———-
D^⅓

For Methane only
Compressible fluids

Question 17

Examples of compressible fluids

Answer 17

Nitrogen
Natural Gas (Ex. Methane)

Question 18

Compressors, Fans & Blowers

Formula for Adiabatic Compressor

Answer 18

E10-67

TO AVOID USING MOLES,
REPLACE RT TO PV

Question 19

Compressors, Fans & Blowers

Why is N added in the formula of Adiabatic Compressor?

Answer 19

If Power is too big, N is added.

N is the # of stages of the compressor.

Question 20

Compressors, Fans & Blowers

What is k or ɣ in the formula of Adiabatic Compressor? What is the value?

Answer 20

ɣ=Cp/Cv
Monoatomic: ɣ=1.67
Diatomic: ɣ=1.4
If CO2, CH4, etc.: ɣ = T2-76

Question 21

Compressors, Fans & Blowers

Formula in determining the pressure in a particular stage in a multi-stage compressor

Answer 21

Ratio, r = (Pn/Po)^1/N
P1 = Po × r
P2 = P1 × r
P3 = P2 × r

Po = initial pressure from Stage 1
Pn = final pressure from Stage N

Question 22

Ratio of Darcy Friction factor and Fanning Friction factor

Answer 22

fD
—- = 4
fF

Question 23

Compressors, Fans & Blowers

Formula of Fans and Blowers

Answer 23

W’ = ∆KE + ∆PE + ∆P/ρ,ave + ΣF

where: ρ,ave = (ρ1 + ρ2) /2

Question 24

Flowmeters: Pitot Tube

Given: Rm
Required: Qv

Answer 24

Qv =vA
➡️ v,ave?
↘️ v,max = c √2gc∆H (E10-11)
↘️ ∆H = Rm (SGm/SG -1) g/gc
↘️ Re,max
↘️ v/v,max

Pitot Coeff, C = 1 if not given
∆H = ∆P/ρ

Question 25

Flowmeters: Pitot Tube

Given: Qv
Required: Rm

Answer 25

∆H = Rm (SGm/SG -1) g/gc
➡️ ∆H=? v,max = c √2gc∆H (E10-11)
➡️ v,max?
↘️ v, ave= Qv/A
↘️ Re
↘️ v/v,max

Pitot Coeff, C = 1 if not given
∆H = ∆P/ρ

Question 26

Flowmeters: Pitot Tube

Given: Qv
Required: Rm

Answer 26

Qv =vA

➡️ V, max = c √2gc∆H
↘️
➡️ Re
➡️ V,ave (T10-10)

Pitot Coeff, C = 1 if not given
∆H = ∆P/ρ

Question 27

In orifice, there’s a sudden contraction of fluid then it will suddenly expand, resulting in high friction and high losses. This phenomenon is called.

Answer 27

VENA CONTRACTA

Question 28

Flow Meters

Formula for Orifice and Venturi Meters

Answer 28

v2 = c √(2gc•∆H)/(1-β⁴) ; E10-20
where: β=D2/D1

Qv = v1A1 = v2A2
where: v=F/A of venturi/orifice

C,orifice = 0.61 if Re>30,000
C,venturi = 0.98 if Re>10,000
Letter V>O

D1 = pipe
D2 = venturi or orifice