Animate shader Like a fluid moving through a pipe

Box8068_31c338ee4b

I am trying to animate a shader so it starts as one color ( or alpha) and the color change moves from
one end to the other. Think a fluid filling or moving through a pipe.
I've tried color gradient it's close but seems a bit unpredictable.
Any ideas?
Thank You
8068

Headwax

removed as obviously ot

WendyLuvsCatz

panning around a cylinder might be better, an exact loop could be done that way
I have been trying forever to get an effective flow shader myself so keep us posted how you go!
(mine always seem to want to ebb and flow istead of going one direction!)

Dream Cutter

remove