HEAT TRANSFER QUIZ

Leidenfrost point is a term concerned with the

Concentration of a corrosive solution by evaporation

Boiling of a liquid on a hot surface

Condensation of the saturated vapor on a cold surface

Heat transfer between two highly viscous liquids

TRUE ANSWER : ?
YOUR ANSWER : ?

Fruit juice (a heat sensitive material) can be concentrated in a __________ evaporator.

High pressure

None of these

Falling film

Long tube

TRUE ANSWER : ?
YOUR ANSWER : ?

Evaporator tubes are generally

Vertical

Horizontal

Random

Inclined

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YOUR ANSWER : ?

The purpose of providing expansion bellows in the shell of tubular exchanger is to

Facilitate increase of shell length, if needed

Account for the uneven expansion of shell and tube bundles

Increase the heating load

Impart structural strength

TRUE ANSWER : ?
YOUR ANSWER : ?

The heat transfer co-efficient in film type condensation is __________ that for dropwise condensation.

Half

Lower than

Greater than

Is same as

TRUE ANSWER : ?
YOUR ANSWER : ?

'Fouling factor' used in the design of a multipass shell and tube heat exchanger is a

Non-dimensional factor

None of these

Conversion factor for individual film heat transfer co-efficient to overall heat transfer co-efficient

Factor of safety

TRUE ANSWER : ?
YOUR ANSWER : ?

Reynold's analogy states that (where, St = Stanton number f = friction factor)

St = f/4

St = 4f

St = f/2

St = f1/2

TRUE ANSWER : ?
YOUR ANSWER : ?

The ratio of total radiating power to the absorptivity of the body depends upon the __________ as per Kirchoffs law.

Temperature of the body

Nature of the body

Wavelength of radiation

None of these

TRUE ANSWER : ?
YOUR ANSWER : ?

A perfect black body is a perfect __________ of radiation

none of the listed here

Both emitter & absorber

absorber

emitter

TRUE ANSWER : ?
YOUR ANSWER : ?

Maximum heat transfer rate is achieved in __________ flow.

Turbulent

Co-current

Laminar

Counter-current

TRUE ANSWER : ?
YOUR ANSWER : ?