Numerical study and experimental validation of the water films and the detachment of drops on drift eliminators

Abstract

Water drift emitted from cooling towers is objectionable for several reasons, mainly due to human health hazards. Generation and control of drift depends mostly on the drift eliminator, a device installed in mechanical cooling towers to prevent the escape of droplets (drift). These eliminators induce a rapid alternation of direction changes, and then the droplets cannot follow the path lines of the airflow within the channels of the eliminator and impact on the plates of it, falling back to the cooling tower ground. This paper focuses on the numerical study of a type of drift eliminator, validated by experimental tests. Three main aspects are considered: the water film formed on the plates of drift eliminators, the size of water droplets detached from this film and the condition of the detachment of these droplets. Good agreement is obtained between numerical and experimental results. The study shows that the behavior of water droplets is very influenced by the air velocity inside the cooling tower.