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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Q. As per Kirchoffs law, the ratio of the total radiating power to the absorptivity of a body depends on the

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Q. If the baffle spacing in a shell and tube heat exchanger increases, then the Reynolds number of the shell side fluid

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Q. The heat transfer by radiation from a mild steel surface is to be reduced by reducing the emissivity of the surface. This can be best achieved by

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Q. __________ paint has the maximum absorption coefficient.

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Q. Which of the following is unimportant in forced convection ?

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Q. 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

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

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Q. Dropwise condensation occurs on __________ surfaces.

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Q. Heat transfer efficiency leading of energy conservation in a heat exchanger can be achieved by

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Q. Trap is used to remove __________ from steam pipe lines.

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Q. A composite flat wall of a furnace is made of two materials 'A' and 'B'. The thermal conductivity of 'A' is twice of that of material 'B', while the thickness of layer of 'A' is half that of B. If the temperature at the two sides of the wall are 400 and 1200°K, then the temperature drop (in °K) across the layer of material 'A' is

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Q. Tube pitch is the __________ of tube diameters and the clearances.

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Q. With increase in the distance between the heat source and the object receiving the heat, the radiation heat transfer

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Q. The heat flux in the nucleate boiling regimes is proportional to (where, ΔT = excess temperature)

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Q. In a 1-1 cocurrent heat exchanger, if the tube side fluid outlet temperature is equal to the shell side fluid outlet temperature, then the LMTD is

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Q. A body is called grey if the monochromatic emissivity of the body is

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Q. In an extended surface heat exchanger, fluid having lower co-efficient

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Q. In a shell and tube heat exchanger, the tube side heat transfer co-efficient just at the entrance of the tube is

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