Introduction
- The boundary layer of a flowing fluid is the thin layer close to the wall
- In a flow field, viscous stresses are very prominent within this layer.
- Although the layer is thin, it is very important to know the details of flow within it.
- The main-flow velocity within this layer tends to zero while approaching the wall (no-slip condition).
- Also the gradient of this velocity component in a direction normal to the surface is large as compared to the gradient in the streamwise direction.
