A. Temperature difference
B. Heat flux
C. That across the entire pipe
D. None of these
Nusselt number is the ratio of the temperature gradient at the wall to_________________? Read More »
Chemical Heat Transfer A. Kcal/hr. m2 °C
B. Kcal/hr.m.°C
C. Kcal/hr.m
D. Kcal/hr. °C
What is the unit of thermal conductivity ? Read More »
Chemical Heat Transfer A. Both the tube sheets fixed
B. Both the tube sheets floating
C. The top tube sheet floating and bottom tube sheet fixed
D. The top tube sheet fixed and the bottom tube-sheet floating
A. 0
B. 1
C. 0.5
D. 0.90
What is the emissivity of a black body ? Read More »
Chemical Heat Transfer A. Watt/m.°K
B. Watt/m2. °K
C. Watt/m2. °K
D. Watt/m4. °K
In SI units, thermal conductivity is expressed in__________________? Read More »
Chemical Heat Transfer A. Conduction only
B. Forced convection only
C. Forced convection and conduction
D. Free and forced convection
In pipe flow, heat is transferred from hot wall to the liquid by__________________? Read More »
Chemical Heat Transfer A. Thermal conductivity
B. Thickness
C. Temperature difference
D. Heat transfer area
A. Increase
B. Decrease
C. Remain unchanged
D. Either increase or decrease; depends on the coolant flow rate
A. Planck’s law
B. Kirchhoff’s law
C. Wien’s law
D. Stefan-Boltzmann law
Which one gives the monochromatic emissive power for black body radiation ? Read More »
Chemical Heat Transfer A. 1 and 0
B. 0 and 1
C. 1 and ∞
D. 0 and 0.5
Absorptivity and reflectivity of a perfect black body are respectively _______________? Read More »
Chemical Heat Transfer