Boundary layer separation is characterised by one of the conditions given below, where ‘Re’ is the Reynolds number for the flow. Select the appropriate conditions ?

Related Mcqs:

1. In the laminar boundary layer flow over a flat plate, the ratio (δ/x) varies as: (where, ‘δ’ is the boundary layer thickness and ‘x’ is the distance from the leading edge in the direction of flow)?

   A. Re
   B. √Re
   C. 1/Re
   D. Re-1/2

2. Which of the following must be followed by the flow of a fluid (real or ideal)? (I) Newton’s law of viscosity. (II) Newton’s second law of motion. (III) The continuity equation. (IV) Velocity of boundary layer must be zero relative to boundary. (V) Fluid cannot penetrate a boundary?

   A. I, II, III
   B. II, III, V
   C. I, II, V
   D. II, IV, V

3. The ratio of hydrodynamic boundary layer to thermal boundary layer thickness in case of liquid metals is__________________?

   A. < 1
   B. 1
   C. > 1
   D. 2

4. In fluid flow, the boundary layer separation cannot occur___________________?

   A. In case of boundaries experiencing form drag
   B. At points of abrupt changes in the flow directions
   C. In laminar flow
   D. None of these

5. The effect of solid boundary on the fluid flow is confined to the boundary layer, except for fluids ?

   A. Having high viscosities
   B. Moving at low velocities
   C. Both A. & B.
   D. Neither A. nor B.

6. Boundary layer separation is caused by the ____________________?

   A. Reduction of pressure below vapour pressure
   B. Reduction of pressure gradient to zero
   C. Adverse pressure gradient
   D. Reduction of boundary layer thickness to zero

7. Boundary layer separation is caused by the_________________?

   A. Reduction of pressure to vapour pressure
   B. Boundary layer thickness reducing to zero
   C. Adverse pressure gradient
   D. Reduction of pressure gradient to zero

8. Boundary layer separation occurs when the____________________?

   A. Pressure reaches a minimum
   B. Cross-section of the channel is reduced
   C. Valve is closed in a pipeline
   D. Velocity of sound is reached

9. For flow past a flat plate, if „x‟ is the distance along the plate in the direction of flow, the boundary layer thickness is proportional to________________?

   A. √x
   B. 1/√x
   C. x
   D. 1/x

10. Bernoulli’s equation for fluid flow is derived following certain assumptions. Out of the assumptions listed below, which set of assumptions is used in derivation of Bernoulli’s equation? A. Fluid flow is frictionless & irrotational. B. Fluid flow is steady. C. Fluid flow is uniform & turbulent. D. Fluid is compressible. E. Fluid is incompressible ?

    A. A, C, D
    B. B, D, E
    C. A, B, E
    D. A, D, E