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

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Q. In a multipass shell and tube heat exchanger, tube side return pressure loss is equal to __________ the velocity head.

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Q. For a given ambient air temperature with increase in the thickness of insulation of a hot cylinderical pipe, the rate of heat loss from the surface would

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Q. In a parallel flow heat exchanger, if the outlet temperature of hot and cold fluids are the same, then the log mean temperature difference (LMTD) is

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Q. For what value of Prandtl number, the Col-burn analogy is valid ?

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Q. In a forward feed multiple effect, the pressure build up will be

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Q. Film boiling occurs at __________ pressure.

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

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Q. 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

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

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Q. Double pipe heat exchangers are used

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Q. Steam traps are provided in steam carrying pipelines to

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Q. A hot liquid is kept in a big room. The logorithm of the numerical value of the temperature difference between the liquid and the room is plotted against time. The plot will be very nearly a/an

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Q. Radiation heat transfer rates does not depend upon the

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Q. Which of the following is correct ?

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Q. Convective heat transfer, in which heat is transferred by movement of warmed matter is described by

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Q. As the difference between the wall temperature and bulk temperature increases, the boiling heat transfer co-efficient

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Q. Heat transfer rate per unit area is called

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Q. Log mean temperature difference (LMTD) cannot be used, if

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Q. The critical radius 'r' of insulation on a pipe is given by

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