Filtered Air Is Pumped Down a Tube of Diameter 50

question 12

Multiple Choice

Filtered air is pumped down a tube of diameter 50 cm into a hospital operating theatre. The idea is that a laminar flow over the patient will prevent contamination. What is the maximum safe speed at which the air can be pumped which will ensure that the flow is not turbulent? The density of air is 1.2 kg m-3 and its viscosity is 1.8x10-5 Pa s.

• A) 1.2 cm s-1.
• B) 3.4 cm s-1.
• C) 6.9 cm s-1.
• D) 12.0 cm s-1.
• E) 23.4 cm s-1.ANS

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Definitions:

Safety Inventory

A quantity of stock maintained in reserve to protect against uncertainties in demand or supply, ensuring that operations continue smoothly.

Lot Size

The quantity of goods considered to be a standard amount for buying or manufacturing, often determined by considering production efficiency and inventory holding costs.

Fill Rate

The percentage of customer demand that is met without backorders or delays, indicating the efficiency of inventory management.

Forecast Uncertainty

The degree of unpredictability in predicting future events, often related to demand, supply, or other market factors.