Q. Air is to be heated by condensing steam. Two heat exchangers are available (i) a shell and tube heat exchanger and (ii) a finned tube heat exchanger. Tube side heat transfer area are equal in both the cases. The recommended arrangement is

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Q. The unit of heat transfer co-efficient in SI unit is

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Q. The number of kg vaporised per kg of steam fed to the evaporator is defined as

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Q. Pick out the wrong statement.

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Q. Economy of a multiple effect evaporator is not influenced much by the

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Q. Increasing the liquor level in the evaporator results in the

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Q. Pick out the wrong statement.

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Q. Convective heat transfer co-efficient in case of fluid flowing in tubes is not affected by the tube length/diameter ratio, if the flow is in the __________ zone.

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Q. The actual temperature drop across the heating surface in an evaporator depends on the

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Q. Which of the following is not used as a medium for high temperature heating ?

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Q. Presence of a non-condensing gas in a condensing vapour

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Q. The average heat transfer co-efficient for laminar film condensation on vertical surface is inversely proportional to (where, ΔT = Temperature drop across condensate film )

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Q. Bulk of the convective heat transfer resistance from a hot tube surface to the fluid flowing in it, is

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Q. Which of the following is concerned with both heat and mass transfer ?

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Q. A backward feed multiple effect evaporator is better than forward feed for concentrating cold feed, because it provides

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Q. A 10 cm diameter steam pipe, carrying steam at 180°C, is covered with an insulation (conductivity = 0.6 W/m.°C). It losses heat to the surroundings at 30°C. Assume a heat transfer co-efficient of 0.8 W/m².°C for heat transfer from surface to the surroundings. Neglect wall resistance of the pipe and film resistance of steam. If the insulation thickness is 2 cms, the rate of heat loss from this insulated pipe will be

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Q. Fouling factor

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Q. In case of vertical tube evaporator, with increase in liquor level, the overall heat transfer co-efficient

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Q. The steam ejector is used to

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Q. For shell and tube heat exchanger, with increasing heat transfer area, the purchased cost per unit heat transfer area

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