Types of Fluid Flow in Pipes: Laminar, Turbulent, Transient

Pipes are circular in cross section area, identical to the shape of a roll of paper towels. We generally use pipes in our homes to supply water from water tank to kitchen, bathroom, etc.

Three different types of fluid flow are written in brief under

1. Laminar flow:

Occurs when the fluid flows in parallel layers, with no mixing between the layers. Where the center part of the pipe flow the fastest and the cylinder touching the pipe isn’t moving at all.

The flow is laminar when Reynolds number is less than 2300.

Laminar flow in pipes

2. Turbulent flow:

In turbulent flow occurs when the liquid is moving fast with mixing between layers. The speed of the fluid at a point is continuously undergoing changes in both magnitude and direction.

The flow is turbulent when Reynolds number greater than 4000.

Turbulent flow

3. Transitional flow:

Transitional flow is a mixture of laminar and turbulent flow, with turbulence flow in the center of the pipe and laminar flow near the edges of the pipe. Each of these flows behaves in different manners in terms of their frictional energy loss while flowing and have different equations that predict their behavior.

The flow is transitional when Reynolds number is in between 2300 and 4000.

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