For pipe flows, head is proportional to __________ at constant capacity(where, D = pipe diameter) ?

Related Mcqs:

1. The pressure drop per unit length of pipe incurred by a fluid ‘X’ flowing through pipe is Δp. If another fluid ‘Y’ having both the specific gravity & density just double of that of fluid ‘X’, flows through the same pipe at the same flow rate/average velocity, then the pressure drop in this case will be__________________?

   A. Δp
   B. 2Δp
   C. Δp2
   D. Δp/2

2. The head loss in turbulent flow in pipe is proportional to(where, V = velocity of fluid through the pipe) ?

   A. V2
   B. 1/V2
   C. 1/V
   D. V

3. For laminar flow of Newtonian fluids through a circular pipe, for a given pressure drop and length & diameter of pipe, the velocity of fluid is proportional to (where, μ = fluid viscosity ) ?

   A. μ
   B. 1/μ
   C. √μ
   D. 1/√μ

4. Consider a centrifugal pump having a specific impeller diameter, fixed impeller speed pumping a liquid of constant density at a particular discharge capacity. With decrease in the capacity of the pump, the _______________ decreases?

   A. NPSH required
   B. BHP required by the pump
   C. Head of the liquid pumped
   D. All A., B. and C.

5. A pipe has a porous section of length L as shown in the figure. Velocity at the start of this section of V0. If fluid leaks into the pipe through the porous section at a volumetric rate per unit area q(x/L)2, what will be axial velocity in the pipe at any „x‟? Assume incompressible one dimensional flow i.e., no gradients in the radial direction ?

   A. VX = V0 + q (x3/L2D)
   B. VX = V0 + ⅓q (x3/L2)
   C. VX = V0 + 2q (x2/LD)
   D. VX = V0 + (4/3) q (x3/L2D)

6. Transition length for a turbulent fluid entering into a pipe is around _____________ times the pipe diameter?

   A. 5
   B. 50
   C. 500
   D. 5000

7. What is the shear rate at the pipe wall, in case of laminar flow of Newtonian fluids in a pipe of diameter ‘D’ & length ‘L’ incurring a pressure drop ‘Δp’ with average velocity ‘Vavg’ ?

   A. D Δp/8L
   B. D Δp/4L
   C. 8 Vavg/D
   D. 4 Vavg/D

8. Consider two pipes of same length and diameter through which water is passed at the same velocity. The friction factor for rough pipe is f1 and that for smooth pipe is f2. Pick out the correct statement ?

   A. f1 = f2
   B. f1 < f2
   C. f1 > f2
   D. Data not sufficient to relate f1 & f2

9. Transition length for turbulent flow in smooth pipe is equal to _____________ times the pipe diameter?

   A. 0.5
   B. 5
   C. 50
   D. 500

10. Nominal Pipe Size (NPS) of a pipe less than 12 inches in diameter indicates its________________?

    A. Inner diameter
    B. Outer diameter
    C. Thickness
    D. Neither inner nor outer diameter