Question

While a propeller gives an axial liquid circulation pattern, a turbine gives ..............

• A. Lateral
• B. Parallel
• C. Axial
• D. Radial

Hint:

Remember: Propellers = axial flow (used for circulation); Turbines = radial flow (used for high shear applications).

Answer 1

The Correct Option is D

In fluid mixing operations, impellers are used to stir fluids inside vessels. These impellers create flow patterns which influence mixing intensity, shear rate, and circulation. Two common impellers are propellers and turbines, each creating distinct flow patterns.
- A propeller impeller is designed to produce an axial flow, which moves the fluid parallel to the shaft of the impeller. This type of flow is ideal for bulk fluid circulation and is commonly used in blending and solid suspension operations.
- A turbine impeller, on the other hand, consists of flat blades attached perpendicularly to the shaft. It creates a radial flow, meaning the fluid is discharged perpendicular to the shaft and moves outward toward the vessel walls. This high-shear region is excellent for gas dispersion and emulsification.
Key comparison: \begin{itemize} \item Propeller → Axial flow (along the shaft) \item Turbine → Radial flow (outward from the shaft) \end{itemize} Hence, the correct term describing the pattern of flow produced by a turbine is radial, making option (4) the correct choice.