The directions of air and water movement through cooling tower fill influence heat transfer, water distribution and installation requirements. Based on this flow arrangement, fill-based cooling towers fall into two main categories: counterflow and crossflow.
Counterflow Cooling Towers
In counterflow cooling towers, water moves downward through the fill while air travels upward. Air and water come into contact while moving vertically in opposite directions. Water is typically distributed through pressurized spray nozzles.
This configuration can offer a compact footprint, particularly in lower-capacity applications, making it suitable for sites with limited space. Installation planning must also account for air inlet clearances and maintenance access.
Crossflow Cooling Towers
In crossflow cooling towers, water falls vertically while air enters the fill horizontally. The air and water streams therefore meet at right angles.
These towers typically use gravity-fed hot water distribution basins. This arrangement can reduce the additional pressure required for water distribution, although total pump head also depends on elevation and piping losses. Access to distribution basins and internal components can simplify inspection and maintenance.
Cooling tower selection should consider cooling capacity, energy consumption, available space and maintenance requirements together.