Test: Heat Transfer - 8 - Mechanical Engineering MCQ

Multiple effect evaporators are commonly used in the manufacture of
P. Paper Q. Superphosphate
R. Sugar S. Fats

Which of the following has the highest thermal conductivity ?

Which of the following is unimportant in forced convection ?

Steam is to be condensed in a shell and tube heat exchanger, 5 m long with a shell diameter of 1 m. Cooling water is to be used for removing the heat. Heat transfer co-efficient for the cooling water, whether on shell side or tube side is the same. The best arrangement is

In a multiple effect evaporator, the effect of boiling point elevation is to

The rate of heat transfer through a pipe wall is given by, . For cylinder of very thin wall, q can be approximated by

Dropwise condensation occurs on __________ surfaces.

For specified tube outside diameter, higher BWG means higher

Pick out the wrong statement.

In case of a vertical tube evaporator, with increase in the liquor level, the __________ is increased.

Electromagnetic radiations propagate in vacuum with a velocity of __________ metre/second.

Heat flux is the time rate of heat transfer per unit

Film boiling occurs at __________ pressure.

Heat flux through several resistances in series in analogous to the current flowing through several

Extended heat transfer surface like fins are used to increase the heat transfer rate. Fin efficiency is defined as the ratio of heat transferred across the fin surface to the theoretical heat transfer across an equal area held at the

Vacuum is generally maintained in the vapour space of an evaporator mainly to

Double pipe heat exchangers are used

Nusselt number (for forced convection heat transfer) is a function of the __________ number.

Pick out the wrong statement.

Which type of heat exchanger is preferred for heavy heat loads ?

Pick out the wrong statement.

While the total emissivity of a perfect black body is unity, the same for a real body is