동축반전로터 정상비행상태 전산유체해석을 위한 깃요소기반 트림해석기법 = TRIM ANALYSIS METHOD USING BLADE ELEMENT THEORY FOR CFD ANALYSIS OF STEADY FLIGHT COAXIAL ROTORS

다국어 초록 (Multilingual Abstract)

In this manuscript, an efficient trim analysis technique is presented for CFD analysis in level flight of coaxial rotors. Trim analysis of coaxial rotors requires a lot of computational resources to obtain gradients of control variables. Blade Element Theory as an efficient alternative method is applied to the computation of control variable gradients. The inflow ratios of upper and lower rotors are obtained from CFD results. These values include aerodynamic interference between upper and lower rotors. Using the inflow ratio from CFD results, Blade Element Theory can take the accurate direction to the trim state. The presented method is validated through the experiments of Dingeldein, and it is confirmed that the trim analysis results are consistent with experimental results and other analysis results.

참고문헌 (Reference)

1 Dingeldein, R.C., "Wind-tunnel studies of the performance of multirotor configurations" NACA 1954

2 Johnson, W., "Rotorcraft Aeromechanics" Cambridge Press 2013

3 Leishman, J.G., "Principles of Helicopter Aerodynamics" Cambridge Press 2006

4 Yoon, S., "Computations of Torque-Balanced Coaxial Rotor Flows" ARC 2017

5 Barbely, N., "Coaxial Rotor Flow Phenomena in Forward Flight" SAE 2016

6 Ruddell, A.J., "Advancing Blade Concept(ABCTM)Development" 13-23, 1976