Correct Answer - Option 3 : 2000
Explanation:
Laminar flow
- A flow is said to be laminar when various fluid particles move in layer or laminae, or well-defined paths, with one layer of fluid, smoothly sliding over an adjacent layer.
Turbulent flow
- A flow is turbulent when various fluid particles move in a zigzag or an irregular manner.
Reynolds number
It is a dimensionless value that is applied in fluid mechanics to represent whether the fluid flow in a duct or pat a body is laminar or turbulent. The value is obtained by comparing the inertial forces with the viscous force.
Reynolds Number = Inertial Force / Viscous Force
Reynolds number for flow in channels is given as,
\({\mathop{\rm Re}\nolimits} = \frac{{\rho VD}}{\mu }\)
Where V is the mean velocity of the flow, ρ is the mass density, μ is the dynamic viscosity and D is known diameter of the pipe.
The Kind of flow is based on the value of Re:
- If Re < 2000, the flow is called laminar
- If Re > 4000, the flow is called turbulent
- If 2000 < Re < 4000, the flow is called transition.
