Question

The velocity field in a fluid is given to be  V = ( 4 x y ) i ^ + 2 ( x 2 y 2 ) j ^ Which of the following statement(s) is/are correct?

Options :

  1. The velocity field is one-dimensional.

  2. The flow is incompressible.

  3. The flow is irrotational.

  4. The acceleration experienced by a fluid particle is zero at (𝑥 = 0, 𝑦 = 0).

Show Answer

Answer :

The acceleration experienced by a fluid particle is zero at (𝑥 = 0, 𝑦 = 0).

Solution :

V = ( 4 x y ) i ^ + 2 ( x 2 y 2 ) j ^

U = 4xy , V = 2(x2 - y2)

δU/δx = 4y , δU/δy = 4x

δV/δx = 4x, δV/δy = -4y

For Incompressible flow :  . V = 0

. V = δ U δ x + δ V δ y  = 4y - 4y = 0

Hence the flow is incompressible.

For irrotational flow ωz = 0

ωz 1 2 ( δ V δ x δ U δ y )   = (4x - 4x) /2 = 0

Hence flow is irrotational.

Acceleration at x = 0, y = 0

ax D U D t = ( U δ U δ x + V δ U δ y )   = 0

ay D V D t = ( U δ V δ x + V δ V δ y )   = 0

Hence acceleration in x and y particle is zero.

Report
More Similar Tests

Related Tests