A Newtonian liquid (ρ = density, μ = viscosity) is flowing with velocity „v‟ in a tube of diameter ‘D’. Let Δp be the pressure drop across the length ‘L’. For a laminar flow, Δp is proportional to_________________?

Related Mcqs:

1. A gas (density = 1.5 kg/m3, viscosity = 2 × 10‒5 kg/m.s) flowing through a packed bed (particle size = 0.5 cm, porosity = 0.5) at a superficial velocity of 2 m/s causes a pressure drop of 8400 Pa/m. The pressure drop for another gas, with density of 1.5 kg/m3and viscosity of 3 × 10‒5kg/m.s flowing at 3 m/s will be________________?

   A. 8400 Pa/m
   B. 12600 Pa/m
   C. 18900 Pa/m
   D. 16800 Pa/m

2. 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

3. Applying a pressure drop across a capillary results in a volumetric flow rate ‘Q’ under laminar flow conditions. The flow rate for the same pressure drop, in a capillary of the same length but half the radius is____________________?

   A. Q/2
   B. Q/4
   C. Q/8
   D. Q/16

4. 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

5. 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

6. For Laminar flow through a packed bed, the pressure drop is proportional to (Vs is the superficial liquid velocity and Dp is the particle diameter) ?

   A. Vs/Dp2
   B. Vs2/Dp2
   C. Vs2/Dp3
   D. Vs/Dp3

7. For laminar flow of a fluid through a packed bed of spheres of diameter d, the pressure drop per unit length of bed depends upon the sphere diameter as_________________?

   A. d
   B. d2
   C. d4
   D. d̅ 2

8. Reynolds number for water flow through a tube of I.D. 5 cm is 1500. If a liquid of 5 centipoise viscosity and 0.8 specific gravity flows in the same pipe at the same velocity, then the pressure drop will______________________?

   A. Increase
   B. Decrease
   C. Remain same
   D. Data insufficient to predict pressure drop

9. The velocity profile exhibited by laminar flow of Newtonian fluids is such that the velocity distribution w.r.t. radius of the circular pipe is a/an ______________ with the apex at the centre line of the pipe?

   A. Hyperbola
   B. Parabola
   C. Semi-circle
   D. Semi-ellipse

10. The ratio of average fluid velocity to the maximum velocity in case of laminar flow of a Newtonian fluid in a circular pipe is_____________________?

    A. 0.5
    B. 1
    C. 2
    D. 0.66