Question

Can you determine the critical distance along a flat surface?

Answer 1

Step-by-step explanation:

Consider a fluid of density, ρ moving with a velocity, U over a flat plate of length, L.

Let the Kinematic viscosity of the fluid be ν.

Let the flow over the fluid be laminar for a distance x from the leading edge.

Now this distance is called the critical distance.

Therefore, for a laminar flow, the critical distance can be defined as the distance from the leading edge of the plate where the Reynolds number is equal to 5 x
`10^(5)`

And Reynolds number is a dimensionless number which determines whether a flow is laminar or turbulent.

Mathematically, we can write,

Re =
`(\rho .U.x)/(\mu )`

or 5 x
`10^(5)` =
`(\rho .U.x)/(\mu )` ( for a laminar flow )

Therefore, critical distance

`x=(5* 10^(5)* \mu )/(\rho * U)`

So x is defined as the critical distance upto which the flow is laminar.