I am willing to animate a flow inside tubes. The problem is, that the thing I would like to achieve, I have done using fractal noise or add grain, but I need this improvised movement to go along the tubes . I have in my scheme few tubes going straight or being convoluted and do not know how to simulate movement of water inside these tubes. I hope you have understood me properly. Is there some other way to do this than playing forever with particle systems ? I have unfortunately not enough time to play with this. Any other idea, hint, clue? Thanx a lot.