Small VTOL platforms envisioned for Urban Air Mobility (UAM) require compact and high–disk-loading propulsion systems, for which coaxial propellers are a suitable option. While counter-rotating coaxial propellers have been widely studied due to their torque-cancellation advantages, combined experimental and CFD-based research on coaxial co-rotating systems remains limited. This study investigates the aerodynamic performance of such a system using RANS-based CFD simulations, complemented by parallel experiments for validation. A pair of 18-inch, two-bladed propellers was arranged in a stacked layout, with mounting angle and inter-rotor spacing treated as key design variables. Results indicate that rotor–rotor interference leads to a maximum Figure of Merit (FoM) of 0.51 when the upper rotor leads at H/D = 0.07 and index angle of +15°. Increasing axial spacing generally improves the performance of both the upper and lower rotors, with the maximum thrust of 17.5N obtained at H/D = 0.07 and +45°. These performance trends were confirmed experimentally, and differences between CFD predictions and measurements remained within 5% for thrust and 6% for torque, demonstrating strong agreement. This study identifies influential design parameters for coaxial co-rotating propeller systems and provides a validated numerical methodology, offering a useful foundation for future high-efficiency Electric Distributed Propulsion System (EDPS) development.

Abstract
1. 서 론
2. 연구방법
    2.1 형상 및 모델링
    2.2 실험장치 구성 및 데이터 측정
    2.3 유동해석 기법
    2.4 격자 형성 기법
    2.5 격자 민감도
3. 연구결과 및 분석
    3.1 단일 프로펠러의 공력 성능
    3.2 동축 동회전 프로펠러의 공력 성능
4. 결 론
후 기
References

• 전수원(Mechanical Engineering, Graduate school of Wonkwang University) | Su Won Jeon
• 박현우(Mechanical Engineering, Under-graduate School of Wonkwang University) | Hyeon U Bak
• 이상욱(Professor, Dept. of Mechanical Engineering, Wonkwang University) | Sang Wook Lee Corresponding author