Chemical Engineering - Heat Transfer

31.
The characteristic dimensionless groups for heat transfer to a fluid flowing through a pipe in laminar flow are
Re.Gz
Nu, Pr
Nu, Pr, Re
Nu, Gz
Answer: Option
Explanation:
No answer description is available. Let's discuss.

32.
Heat transfer rate described by Fourier's law will decrease, if the __________ increases.
thermal conductivity
thickness
temperature difference
heat transfer area
Answer: Option
Explanation:
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33.
A black body does not __________ radiation.
absorb or emit
refract
reflect
both(b) & (c)
Answer: Option
Explanation:
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34.
The capacity of double-effect evaporator is less than half of the capacity of two single effects, each of which is operating over same terminal temperature difference, when the
solution has an elevation of boiling point.
evaporators operate under vacuum.
evaporators opreate at atmospheric pressure.
none of these.
Answer: Option
Explanation:
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35.
Peclet number (Pe) is given by
Pe = Re.Pr
Pe = Re/Pr
Pe = Pr/Re
Pe = Nu.Re
Answer: Option
Explanation:
No answer description is available. Let's discuss.