In a shell and tube heat exchanger, the overall heat transfer co-efficient is proportional to the tube side (volumetric flow rate)0.8. This is valid, only when the ratio of the tube side film resistance to the total resistance is almost equal to____________________?

Related Mcqs:

1. Tube side pressure drop in a 1-2 heat exchanger (for turbulent flow of fluids through the tubes) is about __________ times, that in a 1-1 heat exchanger having the same size & number of tubes and operated at the same liquid flow rate ?

   A. 2
   B. ½
   C. 4
   D. 8

2. In a shell and tube heat exchanger having square pitch, the shell side equivalent diameter is given by (where, P = pitch, d = outside diameter of the tube) ?

   A. 4(P2 – πd2/4)/πd
   B. (P2 – rd2/4)/rd
   C. 4P2/πd
   D. πd/4P2

3. Overall mass transfer co-efficient in case of absorption of __________ in water is based on the gas film co-efficient only, as the mass transfer process is gas film (phase) controlling ?

   A. CO2
   B. SO2
   C. NH3
   D. None of these

4. The ratio of tube length to shell diameter in case of liquid shell and tube heat exchanger ranges from__________________?

   A. 2 to 3
   B. 3 to 5
   C. 4 to 8
   D. 6 to 12

5. Ratio of tube length to shell diameter for a shell and tube heat exchanger is________________?

   A. 8 : 1 to 12 : 1 for both liquid-liquid and gas-gas heat exchangers
   B. 4 : 1 to 8 : 1 for liquid-liquid exchanger
   C. < 4 : 1 for gas-gas exchangers
   D. Both B. & C.

6. In a multipass shell and tube heat exchanger, the shell side cross flow area does not depend upon______________________?

   A. Baffle spacing
   B. Clearance
   C. Pitch
   D. None of these

7. In case of a shell and tube heat exchanger, the effect of L/D on inside film heat transfer coefficient (hi) vanishes after a Reynold number of_____________?

   A. 1000
   B. 3000
   C. 5000
   D. 10000

8. In case of a shell and tube heat exchanger, the minimum shell thickness for carbon steel (inclusive of corrosion allowance) depends on shell diameter and is in the range of ________________ mm?

   A. 3-5
   B. 5-11
   C. 8-15
   D. 12-18

9. Shell side heat transfer co-efficient in case of square pitch as compared to the triangular pitch under similar condition of fluid flow and tube size is_____________?

   A. More
   B. Same
   C. Less
   D. Twice

10. Tube side heat transfer co-efficient for turbulent flow of liquid through tubes is proportional to___________________?

    A. G0.2
    B. G0.5
    C. G0.8
    D. G1.5