Wetted-wall column without surface tension—M. For the film on the wettedwall column discussed in Section 8.10, variations of film thickness are governed by the differential equation: σ d3h dx3 + 6ρQ2...

Wetted-wall column without surface tension—M. For the film on the wettedwall column discussed in Section 8.10, variations of film thickness are governed by the differential equation: σ d3h dx3 + 6ρQ2 5h3 dh dx − 3μQ h3 = −ρg. Consider the situation in which surface tension is negligible. The analytical solution of Eqn. (P8.7.1) is somewhat complicated. However, show that if the film thickness is not too far from its asymptotic value (h/h∞ . = 1), the solution may be approximated by: h h∞ . =1+ ce−15μx/2ρQh∞. in which h∞ = (3Qμ/ρg)1/3 and c is a constant of integration. Give a physical interpretation of Eqn.