viscosity: The Velocity Gradient
The Velocity Gradient
When a fluid is moving through a pipe or a solid object is moving through a fluid, the layer of fluid in contact with the sides of the pipe or the surface of the object tends to be in the same state of motion as the object with which it is in contact; that is, the layer of fluid along the side of the pipe is at rest, while that in contact with the moving object is carried along at the same velocity as the object. If the difference in velocity between the fluid at the sides of the pipe and that at the center, or between the moving object and the fluid through which it is moving, is not too great, then the fluid flows in continuous, smooth layers; that is, the flow is laminar.
The difference in velocity between adjacent layers of the fluid is known as a velocity gradient and is given by
Sections in this article:
- Introduction
- The Coefficient of Viscosity
- The Velocity Gradient
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