A. Clean and dirt free
B. Smooth clean
C. Contaminated cooling
D. Polished
Related Mcqs:
- The heat transfer co-efficient in film type condensation is _______________ that for dropwise condensation?
A. Greater than
B. Lower than
C. Is same as
D. Half - Dropwise condensation is promoted on a/an ______________ surface?
A. Glazed
B. Oily
C. Coated
D. Smooth - The most conducive surface for dropwise condensation to occur is the _____________ surface?
A. Coated
B. Oily
C. Glazed & polished
D. Smooth - For condensation of pure vapors, if the heat transfer co-efficients in filmwise and drop-wise condensation are respectively hf and hd, then__________________?
A. hf = hd
B. hf > hd
C. hf < hd
D. hf could be greater or smaller than hd - Removal of ______________ heat is involved in the condensation of a vapor under saturated conditions?
A. Super
B. Sensible
C. Latent
D. Both B. & C. - If air (a non-condensing gas) is present in a condensing vapor stream, it will ______________ the condensation rate of vapor?
A. Increase
B. Decrease
C. Not affect
D. Increase the condensing film co-efficient as well as - The overall heat transfer co-efficient for a shell and tube heat exchanger for clean surfaces is U0 = 400 W/m2.K. The fouling factor after one year of operation is found to be hd0 = 2000 W/m2.K. The overall heat transfer co-efficient at this time is _____________________?
A. 1200 W/m2.K
B. 894 W/m2.K
C. 333 W/m2.K
D. 287 W/m2.K - Fourier’s law of heat conduction applies to _____________ surfaces?
A. Isothermal
B. Non-isothermal
C. Both A. and B.
D. Neither A. and B. - In a co-current double pipe heat exchanger used for condensing saturated steam over the inner tube, if the entrance and exit conditions of the coolant are interchanged, then the rate of condensation will___________________?
A. Increase
B. Decrease
C. Remain unchanged
D. Either increase or decrease; depends on the coolant flow rate - Film condensation is promoted on a/an _______________________ surface?
A. Oily
B. Coated
C. Clean & smooth
D. Dirty
