Chemical Heat Transfer Subcategories

Chemical Heat Transfer

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____________________?

A. Between two bodies in physical contact with each other
B. Between two bodies not in physical contact with each other
C. From one part of a body to the another part of the same body
D. Both B & C

Nucleate boiling is promoted ___________________?

A. On polished surfaces
B. On rough surfaces
C. In the absence of agitation
D. None of these

Shell side pressure drop in a shell and tube heat exchanger does not depend upon the_________________?

A. Baffle spacing & shell diameter
B. Tube diameter & pitch
C. Viscosity, density & mass velocity of shell side fluid
D. None of these

Which of the following is directly concerned with the heat transfer ?

A. Strouhal number
B. Sherwood number
C. Euler number
D. Grashoff number

Agitated film evaporator is suitable for concentrating _____________ liquids?

A. Foaming
B. Viscous
C. Very thin
D. Corrosive

Which has the lowest Prandtl number ?

A. Liquid metal
B. Aqueous solution
C. Water
D. Lube oil

Double pipe heat exchangers are used__________________?

A. When heat transfer area required is very high
B. When heat transfer area required is very low, i.e. (100-200 ft2).
C. Because it occupies less floor area
D. Because it is less costly

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 ______________?

A. 5.6
B. 0.025
C. 3.5
D. 0.0035

Fluid motion in the natural convection heat transfer between a solid surface and a fluid in contact with it, results from the_________________?

A. Existence of thermal boundary layer
B. Temperature gradient produced due to density difference
C. Buoyancy of the bubbles produced at active nucleation site
D. None of these

A measure of the extent to which viscous heating is important relative to the heat flow resulting from the impressed temperature difference is represented by the _______________ number?

A. Condensation
B. Grashoff
C. Stanton
D. Brinkman