Wave Motion on Falling Water Film

Example 5.8 Wave Motion on Falling Water Film 

A film of water flows down a surface with an inclination 6 from the horizontal of 60°. 

Solving for h (with pi= cp and p= 1 g/cm ), we find h = 5.89 x 10 cm. The average velocity in the film is pgh sin QBpi or 0.981 cm/sec. Note that the more rigorous analysis gives a critical Reynolds number of 0.480 and even smaller values of film thickness and velocity. 

General Reeerences on Interfacial Stability and Wave Motion 

Chandrasekhar, S., Hydrodynamic and Hydromagnetic Stability, Clarendon Press, Oxford, 1961. 

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