A. J.m-2.K-1
B. J.m-1.K-1
C. W.m-2.K-1
D. W-1m2K
Correct Answer: W-1m2K ✔
Last Updated: March 03, 2019
Related MCQs
- For hot feed, forward feeding as compared to backward feeding results in __________ economy?
- In sub-cooled boiling ?
- Heat transfer by conduction results due to the transfer of free electrons, kinetic energy & vibrational energy from one molecule to another. Conduction heat transfer cannot take place__________?
- The thickness of condensate layer in filmwise condensation depends on the__________?
- The heat transfer co-efficient in film type condensation is __________ that for dropwise condensation?
- Steam economy in case of a triple effect evaporator will be __________?
- In a forward feed multiple effect evaporator unit__________?
- Dropwise condensation is promoted on a/an __________ surface?
- Which of the following parameters of the fluid is not very important, while deciding its route in a shell and tube heat exchanger ?
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- Fqra cold viscous feed, backward feed gives __________ than forward feed?
- The Graetz number is concerned with the__________
- The unit of conductance in SI unit is__________?
- Which of the following has the lowest Prandtl number ?
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- Radiation energy is emitted by all the substances, which are above__________?
- The dimensionless group in mass transfer that is equivalent to Prandtl number in heat transfer is__________?
- Loss of heat from untagged steam pipe to the ambient air is by __________?
- In Biot number, the characteristic length used is the ratio of the __________ of the solid?
- Boiling point elevation for a strong and concentrated solution is found by Duhring’s rule, which states that at the same pressure, the boiling point of a solution is a linear function of the __________ of pure water?
- Stefan-Boltzmann law which describes the radiation heat transfer states that, it is proportional to (where, t = temperature in °C T = absolute temperature in ° K) ?
- The equation, (NSt × N2/3 Pr) = f/2, is the __________ analogy ?
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- Prandtl number for most of dry gases is about__________?
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- The purpose of providing expansion bellows in the shell of tubular exchanger is to __________?
- Multipass heat exchangers are used__________?
- It is not recommended to use a 1-2 shell and tube heat exchanger for a particular heat duty, whenever the LMTD correction factor is__________?
- Finned tube heat exchangers__________?
- Fruit juice (a heat sensitive material) can be concentrated in a __________ evaporator?
- The Sieder-Tate correlation for heat transfer in turbulent flow in pipe gives Nu α Re0.8, where, Nu is the Nusselt number and Re is the Reynolds number for the flow. Assuming that this relation is valid, the heat transfer co-efficient varies with the pipe diameter D. as __________?
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- The maximum heat transfer co-efficient from steam heating will be attained when the steam is__________?
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- Which of the following has maximum thermal conductivity ?
- Thermal diffusivity of a material __________?
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- What is the unit of thermal conductivity ?
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- What is the emissivity of a black body ?
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