Question

In centrifugal blower, slip factor is responsible for:-

• A. Increase in friction.
• B. Seal leakage.
• C. Mechanical losses.
• D. Change in actual exit velocity from ideal.

Hint:

Slip factor is a correction for the finite number of blades. If an impeller had an infinite number of infinitely thin blades, the slip factor would be 1.0 (ideal).

Answer 1

The Correct Option is D

Concept: In centrifugal turbomachinery, "slip" refers to the deviation of the fluid's actual path from the path defined by the geometric angle of the impeller blades.

Step 1: Ideal vs. Actual Flow.
Ideally, the fluid should leave the impeller at an angle perfectly tangent to the blade tip. However, because the fluid is not perfectly guided by the blades, the actual tangential velocity is lower than the theoretical value.

Step 2: Definition of Slip Factor.
The slip factor is the ratio of the actual tangential velocity at the exit to the ideal tangential velocity. It accounts for the "slippage" that causes the actual exit velocity to differ from the ideal velocity derived from velocity triangles.