The ratio of down take area to cross-sectional area of the tube, for calandria type evaporator ranges from_________________?

Related Mcqs:

1. In a vertical short tube evaporator (Calandria type), the ______________________?

   A. Tube dia of 2.5-7.5 cms, tube length of 75-200 cms and cylindrical drum dia of 1-6 metres are
   normally used
   B. Area of central downtake is equal to 40 to 100% of total cross-sectional area of the
   surrounding tube
   C. Liquor is inside the tube while the steam is outside the tube
   D. All A., B. & C.

2. Tube height in a calandria type evaporator is normally less than _______________ metres?

   A. 1
   B. 2
   C. 3.5
   D. 5.5

3. Tubes are fixed to the tube sheet (a thick circular metallic plate) by the method of tube rolling and brazing (non-removable) or ferrule connection (removable). Thickness of the tube, sheet is normally ____________ the outside diameter of the tube but in no case it should be less than 22 mm (7/8″)?

   A. Half
   B. Three fourth
   C. Equal to
   D. 1.5 times

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. 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____________________?

   A. ∞
   B. 1
   C. 20.8
   D. 2

6. The ratio of the largest load in a test to the original cross-sectional area of the test specimen is called the _____________ stress?

   A. Yield point
   B. Breaking
   C. Ultimate
   D. None of these

7. Normally, the ratio of the total riser area to the tower cross sectional area (for bubble cap towers of diameter more than 3 ft) is around_______________?

   A. 0.4-0.6
   B. 0.35-0.75
   C. 0.1-0.2
   D. 0.55-0.85

8. In most of the shell and tube heat exchangers, the tube pitch is generally ______________ the tube diameter?

   A. Less than
   B. 1.25-1.50 times
   C. 2.5 times
   D. one-fourth of

9. Minimum tube pitch recommended for shell and tube heat exchangers is about _______________ times the outside diameter of the tube?

   A. 1.25
   B. 1.75
   C. 2.5
   D. 3.5

10. 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.