TP26-01 Redefining fan performance: Tandem Blade Technology in Industrial Cooling Applications

This paper presents a field-based evaluation of Tandem Blade technology applied to axial fans used in cooling towers and air-cooled heat exchangers.
Originally introduced in a 2014 CTI study as a new aerodynamic concept to reduce vortex formation and delay stall, the Tandem Blade has since evolved into a mature and widely adopted solution. The analysis focuses on how this aerodynamic design, intended to reduce turbulence generated by fan blades, reshapes the airflow velocity profile along the blade span, shifting the aerodynamic force inward toward the hub. This improves torque balance and energy performance, without requiring changes to the mechanical configuration of the cooling system. The paper presents three field case studies in different industrial applications, providing direct evidence of the relationship between flow uniformity and fan efficiency. The results confirm the practical value of aerodynamic design in both retrofit and new-build scenarios.