About the Upstream Contamination
The effect through which water pollutants initially floating in a lower recipient, can appear at a higher vessel from which the liquid falls down, is investigated. While is effect has been previously studied experimentally for an inclined channel, here we develop a theoretical model for the case of a vertically falling water beam. Two cases are discussed, a simpler one, in which water flows vertically through a cylindrical tube, and a more complex one, in which water falls freely. For the first case, it is derived an expression for the water flux above which the upward flow of particles stops. For the second one, a relation between the water flux, the sizes of the particles and the height along the water beam is obtained which determines whether the particles can flow up to the higher recipient. In the case of the free fall it follows that the rising of the particles is only possible if the water surface tension is considered, and only happens below a maximal height difference between the two vessels.
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
This work is licensed under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) license.