The heat transfer rate is low in view of the large temperature drop
It is difficult to maintain
It is not economic
None of these
✅ The correct answer is option A.
Engineering MCQs
Correction is applied to LMTD for __________ flow.
Parallel
Counter
Cross
None of these
✅ The correct answer is option C.
Radiation heat losses from satisfactorily insulated high pressure boilar may be about __________ percent.
1
7
18
26
✅ The correct answer is option B.
Air is best heated with steam in a heat exchanger of
Plate type
Double pipe type with fin on steam side
Double pipe type with fin on air side
Shell and tube type
✅ The correct answer is option C.
The main purpose of providing fins on heat transfer surface is to increase the
Temperature gradient
Mechanical strength of the equipment
Heat transfer area
Heat transfer co-efficient
✅ The correct answer is option C.
Peclet number (Pe) is given by
Pe = Re.Pr
Pe = Re/Pr
Pe = Pr/Re
Pe = Nu.Re
✅ The correct answer is option A.
A body cools down from 75°C to 70°C in 10 minutes. It will cool down from 70° C to 65° C in __________ minutes.
10
>10
<10
Either B or C, depends on the mass of the body
✅ The correct answer is option B.
Crystallisation of solids from a homogeneous solution is a/an __________ process.
Exothermic
Mildly endothermic
Highly endothermic
None of these
✅ The correct answer is option A.
Which of the following is unimportant in forced convection?
Reynolds number
Prandtl number
Grashhoff number
None of these
✅ The correct answer is option C.
Which of the following parameters of the fluid is not very important, while deciding its route in a shell and tube heat exchanger?
Corrosiveness & fouling characteristics
Pressure
Viscosity
Density
✅ The correct answer is option D.