March 2019 | Page 818 of 895 | AnsweringExams.Com

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

August 24, 2021March 2, 2019 by admin

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

A. Increase the heating load
B. Impart structural strength
C. Account for the uneven expansion of shell and tube bundles
D. Facilitate increase of shell length, if needed

Multipass heat exchangers are used______________________?

August 24, 2021March 2, 2019 by admin

Multipass heat exchangers are used______________________?

A. Because of simplicity of fabrication
B. For low heat load
C. To obtain higher heat transfer co-efficient and shorter tube
D. To reduce the pressure drop

It is not recommended to use a 1-2 shell and tube heat exchanger for a particular heat duty, whenever the LMTD correction factor is___________________?

August 24, 2021March 2, 2019 by admin

It is not recommended to use a 1-2 shell and tube heat exchanger for a particular heat duty, whenever the LMTD correction factor is___________________?

A. > 0.75
B. < 0.75
C. < 0.50
D. < 0.25

Finned tube heat exchangers__________________?

August 24, 2021March 2, 2019 by admin

Finned tube heat exchangers__________________?

A. Give larger area per tube
B. Use metal fins of low thermal conductivity
C. Facilitate very large temperature drop through tube wall
D. Are used for smaller heat load

Fruit juice (a heat sensitive material) can be concentrated in a ____________ evaporator?

August 24, 2021March 2, 2019 by admin

Fruit juice (a heat sensitive material) can be concentrated in a ____________ evaporator?

A. Long tube
B. Falling film
C. High pressure
D. None of these

The Sieder-Tate correlation for heat transfer in turbulent flow in pipe gives Nu α Re0.8, where, Nu is the Nusselt number and Re is the Reynolds number for the flow. Assuming that this relation is valid, the heat transfer co-efficient varies with the pipe diameter D. as _________________?

August 24, 2021March 2, 2019 by admin

The Sieder-Tate correlation for heat transfer in turbulent flow in pipe gives Nu α Re0.8, where, Nu is the Nusselt number and Re is the Reynolds number for the flow. Assuming that this relation is valid, the heat transfer co-efficient varies with the pipe diameter D. as _________________?

A. D-1.8
B. D-0.2
C. D0.2
D. D1.8

For heat flow through very thick walled cylinder, use ___________mean radius?

August 24, 2021March 2, 2019 by admin

For heat flow through very thick walled cylinder, use ___________mean radius?

A. Arithmetic
B. Logarithmic
C. Geometric
D. Either A. or C.

In a shell and tube heat exchanger, the shell side fluid velocity can‟t be changed by changing the_________________?

August 24, 2021March 2, 2019 by admin

In a shell and tube heat exchanger, the shell side fluid velocity can‟t be changed by changing the_________________?

A. Tube layout
B. Tube diameter
C. Tube pitch
D. Number of baffles

LMTD for evaporators & condensers for a given terminal parameters & set of conditions for counter-flow is equal to that for parallel flow. In such heat exchangers, with one of the fluids condensing or evaporating, the surface area required is the least in the ______________ flow?

August 24, 2021March 2, 2019 by admin

LMTD for evaporators & condensers for a given terminal parameters & set of conditions for counter-flow is equal to that for parallel flow. In such heat exchangers, with one of the fluids condensing or evaporating, the surface area required is the least in the ______________ flow?

A. Parallel
B. Mixed
C. Counter flow
D. Same in either A , B. or C.

The maximum heat transfer co-efficient from steam heating will be attained when the steam is_________________?

August 24, 2021March 2, 2019 by admin

The maximum heat transfer co-efficient from steam heating will be attained when the steam is_________________?

A. Supersaturated
B. Saturated
C. Wet
D. None of these