List of top Mechanical Engineering Questions on Heat Transfer

On the specified surface, if \(35 \%\) of incident radiation energy is reflected and the transmissivity of the body is \(0.3\), then the emissivity of the surface is

If the surface temperature of hot body is doubled, then rate of radiation energy emitted will be enhanced by a factor of

Expansion bellows are provided in the shell and tube heat exchangers in order to

For a fully developed flow through a pipe, how will the heat transfer coefficient (h) change, when the mean flow rate is doubled with all other conditions remaining the same?

The characteristic length (\(\text{L}_{\text{c}}\)) for the calculation of Biot number (\(\text{Bi}\)) for a sphere of radius 'R' subjected to Newtonian cooling is

During a summer day a scooter rider feels more comfortable while on the move than while at rest at a stop light because

For heat transfer calculation in fins, if the Biot number is very small (\(\text{Bi} < 0.1\)) it implies

Expansion bellows are provided in the shell and tube heat exchangers in order to

On the specified surface, if \(35 \%\) of incident radiation energy is reflected and the transmissivity of the body is \(0.3\), then the emissivity of the surface is

If the surface temperature of hot body is doubled, then rate of radiation energy emitted will be enhanced by a factor of

For a fully developed flow through a pipe, how will the heat transfer coefficient (h) change, when the mean flow rate is doubled with all other conditions remaining the same?

During a summer day a scooter rider feels more comfortable while on the move than while at rest at a stop light because

The characteristic length (\(\text{L}_{\text{c}}\)) for the calculation of Biot number (\(\text{Bi}\)) for a sphere of radius 'R' subjected to Newtonian cooling is

For heat transfer calculation in fins, if the Biot number is very small (\(\text{Bi} < 0.1\)) it implies

On the specified surface, if \(35 \%\) of incident radiation energy is reflected and the transmissivity of the body is \(0.3\), then the emissivity of the surface is

During a summer day a scooter rider feels more comfortable while on the move than while at rest at a stop light because

For heat transfer calculation in fins, if the Biot number is very small (\(\text{Bi} \lt 0.1\)) it implies

The characteristic length (\(\text{L}_{\text{c}}\)) for the calculation of Biot number (Bi) for a sphere of radius 'R' subjected to Newtonian cooling is

For a fully developed flow through a pipe, how will the heat transfer coefficient (h) change, when the mean flow rate is doubled with all other conditions remaining the same?

If the surface temperature of hot body is doubled, then rate of radiation energy emitted will be enhanced by a factor of

Expansion bellows are provided in the shell and tube heat exchangers in order to

Arrange the fluids in the decreasing order of heat transfer coefficient \(h\) in forced convection regime for similar operating conditions: A. Air
B. Water
C. Mercury
D. Boiling water

The difference between dry bulb temperature and wet bulb temperature is called:

For a hemispherical furnace with a flat circular base of diameter \(D\), the view factor from dome to its base is: