## 4 Conclusions  
In this research, a specific configuration of multiple unmanned aerial vehicles (UAVs) in a swarm was investigated and evaluated. The arrangement of four UAVs, with two positioned above and two below along the same propeller axis, was extensively studied. The analysis focused on the aerodynamics profile generated by UAV propellers rotating at 10,000 revolutions per minute. Particularly, interactions occurring in close flights were observed at 75 cm between adjacent axes. The effects of UAVs positioned above on UAVs positioned below were meticulously examined and their impact on swarm behavior was investigated. Moreover, investigations into pressure, velocity, and turbulent kinetic energy profiles based on these distances between UAVs revealed the presence of turbulence among them. This study differentiates itself by being the first to model and examine the specific configuration of multiple unmanned aerial vehicles within a swarm using Computational Fluid Dynamics. It focused on the aerodynamic behavior of a square-shaped swarm formation,  
Figure 16: Turbulent kinetic energy on vertical lines. which adds a unique dimension to the analysis. Additionally, advanced CFD techniques, including Multiple Reference Frame (MRF), the k-\(\varepsilon\) turbulence model, parametric placement, and analyses were employed to simulate the swarm configuration. The methodology employed in this research for analyzing swarm formations can serve as a valuable tool for future research and development in UAV swarm technology. It lays the groundwork for further advancements in swarm coordination, navigation, and mission planning. This research marks a significant milestone in understanding the aerodynamic behavior of UAVs in a square-shaped swarm formation flight and optimizing their aerodynamic performance. Additionally, the \"near-UAV phenomenon\" observed during formation/swarm flights was first defined in this research. Defining proximity zones between UAVs should be considered for ensuring the safety of flight operations in UAV swarms. In future studies, proximity distances between drones in swarm formations should be considered for safety. Conceptualization, A.T.I. and B.C. ; methodology, B.C. ; software, B.C. ; validation, B.C. ; formal analysis, B.C. ; investigation, B.C. ; resources, B.C. ; data curation, B.C. ; writing--original draft preparation, A.T.I. and B.C. ; writing--review and editing, A.T.I. ; visualization, B.C. ; supervision, A.T.I. ; project administration, A.T.I. ; funding acquisition, B.C. All authors have read and agreed to the published version of the manuscript. This research was supported by The Scientific and Technological Research Council of Turky (TUBITAK), 2211-C National PhD Scholarship Program in the Priority Fields in Science and Technology 2022/2 (1649B0320209721) as well as by The Council of Higher Education (CoHE) of the Republic of Turkyive, YOK 100/2000 PhD Scholarship Program. Not applicable. The raw data supporting the conclusions of this article will be made available by the authors on request. This study is based on the Ph.D. thesis titled \"Computational Fluid Dynamics Analysis of Rotary-Wing Unmanned Aerial Vehicles Moving as a Swarm\", authored by [PERSON] under the supervision of [PERSON] at Marmara University, Institute of Science and Technology, Department of Mechanical Engineering in Istanbul, Turkey. The author, [PERSON], extends his sincere thanks to his supervisor, [PERSON], for his invaluable guidance and support throughout the research process. The author also wishes to acknowledge The Scientific and Technological Research Council of Turky (TUBITAK) and The Council of Higher Education (CoHE) of the Republic of Turkyive (YOK) for their support. Additionally, the author expresses his deep gratitude to [PERSON], [PERSON], and [PERSON] for their unwavering support and understanding throughout this academic journey. The authors declare no conflicts of interest.