Optimum bottom-stirring in a horizontal cylindrical vessel

Mixing times have been measured in 470 L of water in an 87 cm diameter horizontal cylindrical tank, using air blown in from submerged plugs. It was found that the mixing time depended strongly upon the arrangement of the plugs in the tank. For example, an equally-spaced row of plugs along the tank axis gave a relatively slow mixing process which could be interpreted in terms of a dispersion model. Much faster mixing was achieved with an uneven …