Q. The thermal radiative flux from a surface of emissivity = 0.4 is 22.68 kW/m². The approximate surface temperature (K) is (Stefan-Boltzman constant = 5.67x10⁻⁸ W/m².K⁴)

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Q. Crystallisation of solids from a homogeneous solution is a/an __________ process.

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Q. A multiple effect evaporator has a capacity to process 4000 kg of solid caustic soda per day, when it is concentrating from 10% to 25% solids. The water evaporated in kg per day is

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Q. Value of Prandtl number for water ranges from

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Q. Heat transfer in the laminar sublayer in case of a liquid flowing through a pipe, is mostly by

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Q. In case of a multipass shell and tube heat exchanger, providing a baffle on the shell side __________ the heat transfer rate.

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Q. The local surface conductance for laminar film condensation on vertical surface is (where, t = film thickness)

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Q. Heat transfer co-efficient (h₁) for liquids increases with

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Q. A diathermaneous substance __________ the thermal radiation completely.

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Q. A hot body will radiate heat most rapidly, if its surface is

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Q. Evaporation of 1kg of water from a solution in a single effect evaporator requires about __________ kg of steam.

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Q. A metal wire of 0.01 m dia and thermal conductivity 200 W/m.K is exposed to a fluid stream with a convective heat transfer coefficient of 100 W/m².K. The Biot number is

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Q. Analogy between mass and heat transfer is not applicable in case of

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Q. A __________ surface has the maximum thermal emissivity out of the following.

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Q. Radiant energy received by a body is proportional to (where, d = the distance between the object emitting radiation and that receiving it.)

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Q. Film boiling is usually not desired in commercial equipments, because

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Q. For the same heat transfer area and the terminal conditions, the ratio of the capacities of a single effect evaporator to a triple effect evaporator is

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Q. The variation of thermal conductivity of a metal with temperature is often correlated using an expression of the form K = K₀ + at. where, K is the thermal conductivity and T is the temperature (in °K). The units of 'a' in SI system will be

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Q. Film condensation is promoted on a/an __________ surface.

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Q. Dietus-Boelter equation cannot be used for molten metals mainly due to its very low

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