PROPID 코드 활용 풍력발전기 블레이드 설계 및 CFD 기반 공력특성 비교분석

최서윤,정준희,육래형,하광태,정재호 한국풍력에너지학회 2022 풍력에너지저널 Vol.13 No.3

A methodology of wind turbine blade design has been established with PROPID code, which is an aerodynamic blade design tool developed by UIUC. PROPID code can design and analyze a wind turbine blade in a steady state flow. The methodology of wind turbine blade design includes an initial blade concept design, airfoil selection, basic design, and detailed design steps. Inverse design and performance analysis of the 2.3 MW U113 wind turbine blade was performed to verify the wind turbine blade design methodology. The differences in calculated power between PROPID code and GH Bladed code are under 1.0% in all wind conditions. Both blade shape design and performance analysis results using PROPID code are accurate. The aerodynamic characteristics of a U113 blade were investigated by computational fluid dynamics. Separation flow was captured by a Reynolds-averaged Navier-Stokes steady flow simulation using ANSYS CFX code. The numerical aerodynamic analysis methodology was verified by comparing the analysis results through CFD with BEMT-based program GH Bladed code results. Therefore, the blade design methodology will be applied to develop a super-capacity 20 MW wind turbine blade in the future.

생체 영감을 활용한 블레이드 디자인 제언: 수직축 풍력발전 블레이드 디자인 중심으로

임준빈 한국인더스트리얼디자인학회 2024 산업디자인학연구 Vol.18 No.1

연구 배경: 현재 소형 풍력발전은 전력 생산성이 떨어져 보편화되지 못하였지만, 소형 풍력발전을 고속도로, 지하철 터널 등에 병렬로 다수 설치한다면, 상업용에 가까운 에너지를 얻을 수 있을 거라는 단순한 생각에서 연구가 시작되었다. 따라서 이를 위한 ‘고효율 블레이드 디자인’이 필요하여 연구되었다. 연구 방법: 본 연구는 실제 블레이드를 제작하여 실증적 연구하였으며 다수의 사례를 통해 귀납적 추론으로 진행되었다. paddle 형 항력 블레이드와 NACA 0011 프로파일을 활용한 블레이드, 이를 어류의 몸동작 형태로부터 영감을 받아 프로파일을 휜 블레이드(Bent NACA 0011) 등 3종을 제작하여 비교 실험하였다. 연구 결과: 항력 블레이드의 회전 속도는 고속으로 상승하는 장점에 비해 풍속을 초과하지 않았다. NACA 0011은 이론적으로 풍속을 초과한다고 하였지만 풍속에 근접한 수준으로 미미하였다. Bend NACA 0011은 회전 시작 2분 40초경 풍속을 초과하여 고속으로 회전하였다. 결론: 생체영감으로 설계된 Bent NACA 0011 블레이드의 결과를 통해 회전 방향으로 휘어진 형태인 블레이드가 수직축 풍력발전 블레이드로 효율적임을 확인하였다. 항력 블레이드는 효율이 낮다고 알려졌음에도 저속의 풍속에서도 기동하고 빠르게 상승하는 것을 통해 많이 활용되는 이유를 파악하였다. Background: Currently, small wind power generation is not common due to low power productivity, but the study began with the simple idea that close to commercial energy could be obtained if a large number of small wind power generation was installed in parallel on highways and subway tunnels. Therefore, a 'high-efficiency blade design' was needed for this study. method: Research method: This study was conducted empirically by manufacturing actual blades and conducted by inductive reasoning through several cases. Three types were manufactured and compared: a paddle-type drag blade, a blade using the NACA 0011 profile, and a Bent NACA 0011 blade that was inspired by the shape of the fish's body movements. Results: The rotational speed of the drag blade did not exceed the wind speed compared to the advantage of rising at a high speed. NACA 0011 was theoretically said to exceed the wind speed, but it was insignificant at a level close to the wind speed. Bent NACA 0011 exceeded the wind speed and rotated at high speed around 2 minutes and 40 seconds after the start of the rotation. Conclusion: Through the results of the Bent NACA 0011 blade designed as bioinspiration, it was confirmed that it was efficient to bend the blade rotating around the vertical axis in the rotation direction. The reason why drag blades are widely used by maneuvering even at low wind speeds was identified.

사이드펄링을 활용한 과풍속제어장치에 대한 풍동시험 연구

조태환,김양원,장일영,박철완,김정환 한국풍력에너지학회 2017 풍력에너지저널 Vol.8 No.2

A wind tunnel test for the side-furling device that was used for a horizontal type small wind turbine to reducethe output power in a high wind speed condition was conducted in a 5 m × 3.75 m open-jet test section. Asimple experimental wind turbine model with a “MEXICO blade” and electric motor was used to simulate thesmall wind turbine system. The furling force of the tail was measured by a force sensor installed on the furlingarm and the yawing moment of the turbine was measured by a moment sensor installed on the turbine strut. The turbine power was calculated by using the torque of the rotating axis and the rotational speed of the blade. Force characteristics of the tail system were studied by changing the arm length, wind speed and flow direction. Moment characteristics of the nacelle and blade system were studied by changing the offset distance, wind speedand RPM. Moment equilibrium conditions for the typical wind speed were estimated from those test results andconfirmed by a fixed-tail-angle test. A free-tail-angle test was also conducted to verify the effect of theside-furling device in high wind speed conditions.

운전정지 조건에서 5 MW 수평축 풍력터빈 로터의 풍하중 해석

유기완,서윤호 한국풍공학회 2018 한국풍공학회지 Vol.22 No.4

본 연구에서는 운전 정지 상태로 회전하지 않는 수평축 해상 풍력터빈 로터에서 발생하는 풍하중을 풍속, 요 각도, 방위각, 피치 각도를 달리하면서 대기경계층 내에서 작동하는 조건으로 평가하였다. 하중 예측 결과의 검증을 위해 단순화 한 블레이드 형상에대한 블레이드 요소이론과 단순 계산치를 이용하여 얻어낸 공력 하중을 상호 비교하였으며, 코드와 비틀림 각도가 블레이드 스팬 방향에 따라 변하는 NREL 5 MW급 대형풍력터빈 로터에 대해서는 NREL에서 개발한 FAST 해석 결과와 본 연구의 해석 결과를 비교함으로써 해석 결과의 정확도를 검증하였다. 로터의 하중은 허브 중심을 원점으로 하는 고정된 3축 좌표계에 대해서 힘과 모멘트로 표현되는 6분력 하중으로 나타내었다. 따라서 이 결과는 풍력터빈 시스템의 동적 거동 해석과 로터에서 발생되는 전도 모멘트를 견디기위해 필요한 지지 구조물의 기초하중 자료로 적용할 수 있다. In this study, wind loads exerted on the offshore wind turbine rotor in parked condition were predicted with variations of wind speeds, yaw angles, azimuth angle, pitch angles, and power of the atmospheric boundary layer profile. The calculated wind loads using blade element theorem were compared with those of estimated aerodynamic loads for the simplified blade shape. Wind loads for an NREL’s 5 MW scaled offshore wind turbine rotor were also compared with those of NREL’s FAST results for more verification. All of the 6-component wind loads including forces and moments along the three axis were represented on a non-rotating coordinate system fixed at the apex of rotor hub. The calculated wind loads are applicable for the dynamic analysis of the wind turbine system, or obtaining the over-turning moment at the foundation of support structure for wind turbine system.

풍력 발전기 블레이드의 구조 개선에 대한 연구

은원종,심지수,박철우,신상준 한국풍력에너지학회 2016 풍력에너지저널 Vol.7 No.1

The wind power energy has been suggested as alternative energy source because it is economically more feasible than other alternative energy technologies. The size of commercial wind turbines has dramatically increased to improve their energy conversion efficiency. The wind turbine blade loads become more important as the wind turbines increase in their size. The modern large-size wind turbine blades generally use sandwich structures and thick laminates to withstand the aerodynamic loads. And the biplane blade design was proposed to use a biplane inboard region to improve overall performance of large blades. The individual pitch control (IPC) facilitates structural load reduction without blade shape alteration. Active flow control methods, such as trailing-edge flap, adaptive compliant wing, micro-tab, have been proposed as viable and effective devices for active load control applications. In order to alleviate the wind turbine blade loads, various researches are under going.

CFD를 활용한 MW급 풍력발전기 블레이드 와류 발생기 형상 최적화 및 공력 특성 분석

문현기,박선호,하광태,정재호 한국풍력에너지학회 2021 풍력에너지저널 Vol.12 No.2

The aerodynamic characteristics of a vortex generator (VG) on a multi-MW wind turbine blade was investigated by computational fluid dynamics (CFD). VGs are essentially small fins that are installed toward the root of the wind turbine blade to reduce airflow separation. Separation flow on the wind turbine blade suction surface was captured by a Reynolds-averaged Navier-Stokes (RANS) steady flow simulation using a general-purpose code, ANSYS CFX. The numerical analysis methodology was verified by comparing the blade aerodynamic analysis results through CFD with blade element momentum theory (BEMT)-based program GH-Bladed results. An aerodynamic sensitivity study of the VG according to the design parameters of the VG was performed. Optimization was carried out by targeting parameters with low eddy current dissipation rates. According to the simulation, the VG reduces separation in the wind turbine blade root region. Furthermore, it was found that the aerodynamic coefficient of the wind turbine with VG installation increases up to 2.80% at the rated power.

BEM 방법을 적용한 2MW 육상용 풍력터빈의 윈드 쉬어 추력 변동 고찰

임채욱 한국풍력에너지학회 2018 풍력에너지저널 Vol.9 No.2

Multi-MW wind turbines have very long and large blades. There are some factors that exert asymmetric dynamic thrusts on a blade. Wind shear is one of the main factors that produce asymmetric dynamic loads on a blade of a multi-MW wind turbine. In this paper, a 2 MW on-shore wind turbine that has three blades with a rotor radius of 40 m and hub height of 60 m is considered and thrust variations on a blade under wind shear are calculated according to the wind speed. The commercial software GH Bladed is used for calculating thrust variations based on the blade element momentum (BEM) method. And the amplitudes of the thrust variations by wind shear with varying wind speed are investigated by introducing a "wind shear coefficient of thrust variation" based on the steady-state value of thrust without wind shear.

PSO를 이용한 풍력발전 블레이드의 공기역학적 최적설계

리껀,박명성,김영철,백태현 한국기계기술학회 2017 한국기계기술학회 학술대회논문집 Vol.2017 No.04

The object of research in Based on 1.5MW wind turbine blade. This paper has carried out the aerodynamic shape optimization design of wind turbine blade. Based on the aerodynamic basic theory of wind turbine blade design and combined with particle swarm optimization algorithm, the design optimization model of the aerodynamic shape of blade is established. The calculation programs are written by use of MATLAB and calculate chord length and torsion angle of the blade. Then the shape of wind turbine blade is obtained. As research we can know that the chord length is decreased after optimization design of wind turbine blade, The optimized blade not only meets the actual manufacturing requirement, but also has the largest wind energy utilization coefficient.

고유익형 KA2가 적용된 풍력 블레이드의 회전토크와 추력에 익형의 항력이 미치는 영향 분석

강상균,박성수,이상일,이장호 한국풍력에너지학회 2021 풍력에너지저널 Vol.12 No.1

Many studies have been conducted on the design of wind turbine blades and the several forces necessary for the operation of a wind turbine and its integrated load analysis such as thrust and torque generated at the design point. However, studies on the effect on such several forces by the drag force of a horizontal axis wind turbine blade have not been sufficient. The analysis of the drag effect of an airfoil on the rotational torque and thrust of wind turbine blades requires more precise design performance and drive performance of wind turbines. Therefore, it is necessary to review the degree of effect of airfoil drag force on rotational torque and thrust during the development of wind turbine blades. In this study, a wind turbine blade with the original airfoil KA2 was developed and manufactured for a performance test and the drag effect of an airfoil on the rotational torque and thrust of the horizontal axis wind turbine blade was analyzed. It was confirmed that the drag effect on torque is larger than that of thrust and that the effect of the drag force to the lift force is larger from the root to the tip.

MG-set 기반의 풍력터빈 동적 시뮬레이터 개발

원병철,전태수,백인수 한국풍력에너지학회 2021 풍력에너지저널 Vol.12 No.4

In this paper, a dynamic simulator based on an MG set was implemented for a scaled wind turbine model with a rated power of 40 W with an operating mechanism similar to that of a MW-class large wind turbine. A test bench constituting the simulator hardware was initially designed and manufactured by Carlo L. Bottasso's research team at the Technical University of Munich. In this study, part of the test bench was modified and redesigned, and a simulator capable of dynamic simulation was developed by applying a GUI for operation and monitoring, and a dynamic driving algorithm and turbine control algorithm. A DC motor is connected to the main shaft to emulate the rotor rotation. Also, in order to simulate the change in the rotor rotation speed according to the change in wind speed, motor speed control was performed using a numerical model of the wind turbine based on MATLAB Simulink. The generator part was directly applied to the MG set together with the nacelle part of the target wind turbine scale model. To verify the performance of the MG set-based dynamic simulator, it was compared with the existing MATLAB Simulink dynamic simulation model. The main performance data between the experimental results and the MATLAB Simulink-based dynamic simulation were compared, and an error within 1 % was confirmed. Using the MG set-based dynamic simulator built in this study, it was confirmed that it was possible to verify the performance of the wind turbine controller for dynamic wind in the laboratory before a wind tunnel test.