The value of Lewis number (Le = Sc/Pr) for air-water vapour system is around_________________?
Correct answer: A. 1
- A. 1
- B. 0.24
- C. 3.97
- D. 600
Explanation
For air-water vapour, thermal and mass diffusivities are of similar magnitude, so Sc and Pr are both close to unity. Their ratio, the Lewis number, is therefore approximately 1 rather than 0.24 or 3.97.
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