생체모방기술을 적용한 소음 저감 프로펠러 모델링 및 유동 해석 시뮬레이션 = Noise Reduction Propeller Modeling and Fluid Analysis Simulation Utilizing Biomimetic Technology

국문 초록 (Abstract)

본 연구는 생체모방기술을 적용하여 드론 프로펠러에서 발생하는 소음을 저감하는데 목적을 두고 있다. 군사용 드론의 소음 발생은 잠입 및 전투 운용 시 적군에게 피탐 가능성이 증가하여 쉽게 파괴될 수 있는 문제가 있다. 이에 우리는 소음 저감을 위해 비행 중 소음이 거의 발생하지 않는 올빼미과(Strigidae) 조류의 깃털에서 관찰되는 Leading Edge Serration (LES) 구조를 모방하였다. 3D Computer-Aided Design (CAD) 모델링을 통해 Normal Propeller (NP)와 Serrations Attached Propeller (SAP)을 제작하고, 이를 Computational Fluid Dynamics (CFD) 유동 해석 시뮬레이션을 통해 소음 수준을 비교 분석하였다. 소음 분석 이외에도, 프로펠러 구조 변형에 따라 비행 효율 성능 감소를 우려하여 공기역학적 계수 분석을 진행하였다. 그 결과, SAP 모델들은 NP와 비교하였을 때 항력계수의 감소, 양력계수의 증가, 양항비 증가에 따른 비행 효율성이 증가하였고, 드론 실 운용 rpm 범위에서 소음 저감이 관찰됐다. 이는 Serrations에 의해 공기흐름을 작은 난류로 분산되어 양력이 증가하고, 와류가 작게 형성됨에 따라 항력과 소음이 감소하기 때문이다. 본 연구를 통해 군사용 드론에 생체모방기술 적용 가능성을 확인하였다. Serrations 이외에 Fringes와 같은 구조를 추가로 적용하여 소음 저감 효과를 높일 수 있으며, 군 운용 목적에 따른 다양한 생체모방기술 연구에 적용이 가능하다.

다국어 초록 (Multilingual Abstract)

This study aims to reduce noise generated from drone propellers by applying biomimetic technology. The noise generation of drones increases the possibility of being detected by enemy forces during infiltration and combat operations, and there is a problem that they can be easily destroyed. Therefore, in order to reduce noise, the Leading Edge Serrations (LES) observed in the feathers of owls (Strigidae), where noise during flight is minimal, was mimicked. Normal Propeller (NP) and Serrations Attached Propeller (SAP) were fabricated through 3D Computer-Aided Design (CAD) modeling, and the noise level was compared through Computational Fluid Dynamics (CFD) flow analysis simulation. In addition to noise analysis, aerodynamic coefficient analysis was conducted due to concerns about a decrease in flight efficiency performance due to propeller structure deformation. As a result, SAP models exhibited a decrease in drag coefficient, an in- crease in lift coefficient, and lift-to-drag ratio compared to NP, leading to enhanced flight efficiency, and noise reduction was observed within the drone’s actual operating RPM range. This is due to serrations dis- persing the air flow into small turbulence, increasing lift, and reducing drag and noise by forming small eddy. This study confirmed the potential for applying biomimetic technology to the development of military drones. In addition to serrations, structures such as fringes can be applied to enhance noise reduction effects, and can be utilized to various biomimetic technology studies for military operational purposes.

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