Session: 10-01 Experimental Aerodynamics of Fans

Submission Number: 178175

Wall Effects on Airflow Performance of HVLS and Ceiling Fans 

High Volume Low Speed (HVLS) fans are increasingly implemented in industrial and commercial environments due to their ability to deliver large airflow volumes at low rotational speeds. This study presents a comparative evaluation of HVLS and conventional ceiling fans, employing computational fluid dynamics (CFD) simulations validated by air testing to quantify airflow performance. The analysis examines the influence of ceiling height, floor distance, and sidewall proximity on air movement behavior. Results indicate that, with similar efficacy, HVLS fans produce approximately 45 times greater volumetric flow rate (CFM) and achieve nearly seven times the spatial spread and throw relative to ceiling fans. Both fan types generate a low-velocity region, or “dead zone,” directly beneath the fan where the impinging jet meets the floor; however, the extent and intensity of this zone vary significantly with ceiling height, floor distance, and sidewall presence. Sidewalls were shown to redirect radial outflows into recirculating currents, enhancing localized floor-level velocities while reducing uniformity of coverage. Overall, HVLS fans demonstrated superior capability for sustaining large-scale air circulation in high-ceiling or wide-span spaces, whereas conventional ceiling fans were more effective in smaller, confined settings requiring localized airflow. These results provide a framework for integrating CFD analysis into fan system selection and for optimizing fan placement to improve energy efficiency and occupant comfort.

Presenting Author: Juhi Chowdhury Greenheck Group

Presenting Author Biography: Juhi Chowdhury is a Senior CFD Engineer at Greenheck Group, where she applies computational and analytical modeling to advance fan aerodynamics and performance optimization. Juhi earned her Ph.D. in Aerospace Engineering from the University at Buffalo, where her research focused on experimental and analytical modeling in aerodynamics.

Authors:

Juhi Chowdhury Greenheck Group
Vijaya Kollipara Greenheck group
Tyson Sargent Greenheck Group
Duncan Sparks Greenheck Group