Impact of the Ceiling Effect on Thrust in Quadcopters: Analysis of Ceiling Distance and Rotor Separation in Baseline and Commercial UAVs

The use of unmanned aerial vehicles (UAVs) has experienced significant growth in recent years. The versatility and adaptability of multicopter drones make them ideal for operating in challenging environments, which often feature physical obstacles that induce complex aerodynamic interactions. Among these interactions, the effect of proximity to ceiling walls has not been extensively studied using experimental techniques or numerical simulations, despite being a relevant factor for operation in confined spaces. To advance the understanding of the ceiling effect in quadcopter drones, a comprehensive campaign based on computational fluid dynamics (CFD) simulations was conducted using both simplified and commercial drone models, and key parameters, such as the speed of the rotors, the drone-ceiling separation, and the spacing between rotors, were explored. The ceiling effect on thrust magnitude in quadcopters was quantified under various conditions, and the results show that as the distance to the ceiling decreases, thrust increases by up to 10%. Conversely, greater spacing between rotors resulted in a diminished ceiling effect, whereas rotor speed was found to have a minimal impact. These findings underscore the existence of a potentially hazardous ceiling suction effect that might compromise the stability of the quadcopter. However, this effect also presents opportunities for energy-saving strategies by leveraging the increased thrust in specific operational scenarios. This study sheds light on the complexities of aerodynamic interactions near ceilings and provides valuable insights into drone design and performance optimization, which is particularly relevant for confined environments such as warehouses and urban areas.