Oblique shock and Expansion wave CO3

Which of the following assumptions are made for the analysis of Fanno flow? (i) Area of the duct is constant (ii) The flow is steady and one-dimensional (iii) There is no work or heat transfer (iv) Wall friction is the only driving potential for the flow.

• all of them

• (i), (ii) and (iii)

• (i) and (ii)

• (ii), (iii) and (iv)

In analyzing simple frictional flows, the wall frictional force is related to the _____ through an empirically determined friction coefficient.

• heat transfer

• work transfer

• bulk flow properties

• flow area

In Rayleigh flow, for a given set of initial conditions, there is a limiting state where the entropy is maximum, and at that state fluid velocity is

• greater than local acoustic speed

• less than local acoustic speed

• equal to local acoustic speed

• none of the above

If a body moves in a perfect frictionless fluid and shock waves are generated, a drag force called _____ is produced.

• shock drag

• wave drag

• form drag

• skin friction drag

The wave drag is

• dependent on skin friction drag

• dependent on form drag

• dependent on skin friction drag and form drag

• independent of skin friction drag and form drag

All the normal shock relations are applicable to ______ ahead and behind an oblique shock.

• enthalpies

• densities

• tangential components of velocities

• normal components of velocities

The thermodynamic properties of the gas behind the oblique shock wave depend on _____.

• Mach number and velocity

• Flow deflection angle

• upstream conditions and flow deflection angle

• wave angle

Pick out the wrong statement (i) Oblique shock wave emanates from concave corner (ii) Expansion wave emanates from convex corner (iii) Entropy of the fluid increases across an oblique shock wave (iv) None of the above

• (i)

• (ii)

• (iii)

• (iv)

A steady uniform two-dimensional supersonic flow around a convex corner is known as ____.

• Isentropic expansion

• Isothermal expansion

• Prandtl Meyer expansion

• None of the above

As a fluid flows around a convex corner, it accelerates from M₁ > 1 to

• M₂ > M₁

• V₂ > V₁

• p₂ < p₁

• all the above