# Laminar Flow vs Turbulent Flow vs Transitional Flow | Difference between Laminar Flow,Turbulent Flow,Transitional Flow

This page compares Laminar Flow vs Turbulent Flow vs Transitional Flow and mentions difference between Laminar Flow, Turbulent Flow and Transitional Flow. Reynolds Number equation and its limits are mentioned for these types of flow.

Fluid motion in pipe can be characterized in three ways:
➨Laminar flow
➨Turbulent flow
➨Transitional flow

## Laminar Flow

In this type of flow, fluid travels as parallel layers(i.e. streamlines) and they do not mix as they move along the direction of flow.

## Turbulent Flow

In this type of flow, fluid do not travel in parallel layers but moves in random manner in which only average motion of fluid is parallel to pipe axis. The figure-1 depicts laminar flow vs turbulent flow.

## Transitional Flow

In this type of flow, both laminar and turbulent types present at different points along pipeline or both of these flow may switch one after the other.

## Reynolds Number

Definition: It is the ratio of inertia forces in the flow to viscous forces in the flow (η). Reynolds Number is denoted by Re as mentioned in the equation above. It is calculated based on fluid properties and does not take factors such as pipe roughness, bends and valves into consideration.

• If Re < 2000, flow will be laminar as viscous forces dominate in the flow.
• If Re > 4000, flow will be turbulent as inertia forces dominate in the flow.
• If Re is between 2000 and 4000, flow will be transitional and either of the above mode exists.