(Le/D) for a Tee (used as elbow, entering run) would be around _______________________?

Related Mcqs:

1. (Le/D) for a Tee (used as elbow, entering branch) would be ____________________?

   A. Less than that for Tee (used as elbow, entering run)
   B. More than that for Tee (used as elbow, entering run)
   C. Around 90
   D. Both B. and C.

2. Le/D) for 90° elbow (medium radius) and 90°square elbow would be respectively around___________________?

   A. 25 and 60
   B. 3 and 5
   C. 100 and 250
   D. 250 and 600

3. Pressure drop due to pipe fittings can be estimated by the equation, ΔP/ρ = 4f, (Le/D) (V2/2gc) where, Le = equivalent length of straight pipeline which will incur the same frictional loss as the fitting and D = diameter of the fitting. The value of (Le/D) (dimensionless) for 45° elbow and 180° close return bends would be respectively around______________________?

   A. 5 and 10
   B. 45 and 75
   C. 180 and 300
   D. 300 and 500

4. In a heat exchanger, shell side fluid velocity can be changed by changing the tube _______________________?

   A. Layout
   B. Pitch
   C. Both A. & B.
   D. Neither A. nor B.

5. In packed towers provided with pall rings liquid redistributors are positioned at heights of every 6 metres or 5-10 times the column diameter, whichever is less. Maximum size of the pall rings should not exceed _______________________ of the column diameter?

   A. 1/10-1/15th
   B. 1/5-1/10th
   C. 1/20-1/30th
   D. 1/2 to 1/4th

6. Flanges are connected to pipes by _______________________?

   A. Screwing
   B. Welding
   C. Brazing
   D. All A., B. and C.

7. In a shell and tube heat exchanger, the shortest centre to centre distance between the adjacent tubes is__________________?

   A. Called tube pitch
   B. Called tube clearance
   C. Always less than the diameter of the tube
   D. None of these

8. In a shell and tube heat exchanger, the clearance of the tube is generally___________________?

   A. Not less than one-fourth of the tube diameter or 3/16″
   B. More than the tube diameter
   C. Equal to the tube diameter
   D. More in case of triangular pitch as compared to the square pitch tube layout

9. A single pass air heater is connected to a two pass unit. For the air flow rate and other conditions remaining the same, the film heat transfer co-efficient for air will vary in the ratio of_________________?

   A. 2
   B. 20.8
   C. 20.2
   D. None of these

10. In a shell and tube heat exchanger, tube side _______________ of the mass velocity?

    A. Heat transfer co-efficient is proportional to 0.8th power
    B. Pressure drop is proportional to the square
    C. Both A. & B.
    D. Neither A. nor B.