Open pan evaporation
Long tube vertical evaporator
Agitated film evaporator
None of these
✅ The correct answer is option A.
Heat Transfer MCQs
At Pr > 1, conduction in an ordinary fluid flowing through a heated pipe is limited to the
Buffer zone
Turbulent core
Both A and B
Viscous sub-layer
✅ The correct answer is option D.
If h₁ = inner film co-efficient and /h₂ = outer film co-efficient, then the overall heat transfer co-efficient is
Always less than h₁
Always between h₁ and h₂
Always higher than h₂
Dependent on metal resistance
✅ The correct answer is option B.
When vaporisation takes place directly at the heating surface, it is called
Film boiling
Nucleate boiling
Vapour binding
None of these
✅ The correct answer is option B.
The film co-efficient between condensing vapour and metal wall increases with
Increasing temperature of the vapour
Decreasing temperature of the vapour
Increasing viscosity of the film of condensate
Increasing temperature drop
✅ The correct answer is option A.
Tube expansion allowances exist in __________ heat exchanger.
Multipass fixed tube sheet
U-tube
Single pass fixed tube sheet
None of these
✅ The correct answer is option B.
The maximum heat transfer co-efficient from steam heating will be attained when the steam is
Supersaturated
Saturated
Wet
None of these
✅ The correct answer is option B.
For heat flow through very thick walled cylinder, use____mean radius.
Arithmetic
Logarithmic
Geometric
Either A or C
✅ The correct answer is option B.
Which of the following is concerned with both heat and mass transfer?
Lewis relationship
Nusselt number
Kutateladze number
Froude number
✅ The correct answer is option A.
Economy of a multiple effect evaporator is not influenced much by the
Boiling point elevations
Temperature of the feed
Rate of heat transfer
Ratio of the weight of the thin liquor to thick liquor
✅ The correct answer is option A.