Correlation for residual viscous fluid film?

[colemanstoops]

What I'm looking for is a literature correlation that estimates the quantity of a residual amount of viscous fluid in a horizontal pipe after flow ceases and the line is allowed to drain at least superficially. Say, for example, we have a 560 SSU oil pumped in a horizontal 3" line; the pump is shut off and the discharge of the line remains open at the downstream end. What I'm looking for is some means of estimating what might be left clinging to the pipe ID after the pipe ostensibly "drains" grossly (that is, the volume per running foot, let's say, that would contribute to drips). Any suggestions, please?

 

[BigInch]

Gravity Flow in a partially filled cylinder.

Independent events are seldomly independent.

 

[goodguy1405]

The question your answering is a dark area in fluid dynamics. The Navier-Stokes equations address this in a way but to tell you exactly how much is left over is a mystery. I would suggest you shut the pumps off and catch the remaining fluid in a measuring cup to see APPROXIMATELY how much is left clinging to the wall for that run. Other than that if you solve the Navier-Stokes equations 1. You will have your answer 2. You win a million dollars!!!(for real)
There are work around for what your seeking but nothing accurate.