Question

What is the primary feature of Couette flow?

• A. Fluid motion driven solely by pressure gradient
• B. Fluid between two surfaces moving relative to each other
• C. Fluid in a circular pipe
• D. Fluid flowing through an expanding channel

Hint:

Basic Flows. Couette Flow: Shear-driven flow between parallel surfaces in relative motion. Poiseuille Flow: Pressure-driven flow between stationary surfaces or in a pipe.

Answer 1

The Correct Option is B

Couette flow describes the laminar flow of a viscous fluid in the space between two parallel plates (or concentric cylinders), where one surface is moving relative to the other.
The motion of the fluid is driven primarily by the viscous drag exerted by the moving surface.
Plane Couette flow refers to the case between parallel plates, while Taylor-Couette flow refers to the case between rotating cylinders.
Pressure gradients can also be present (generalized Couette flow), but the defining characteristic is the flow induced by the relative motion of the boundaries.
Flow driven solely by pressure gradient between stationary plates is Poiseuille flow.