Velocity data-based determination of airfoil characteristics with circulation and fluid momentum change methods, including a control surface size independence test

Abstract An experimental method for determination of aerodynamic loads is presented. It based on velocity vector field results obtained with Particle Image Velocimetry (PIV). As PIV an optical measurement technique, the developed load can be defined as noninvasive. shown that only information needed to estimate lift and drag forces exerted a body placed in flow distribution measured around investigated object. Therefore, provide sufficient input data used. Fundamental fluid mechanics theories were employed develop algorithms estimation. Determination force circulation calculations. by integrating along closed-loop encircling body. essential achievement made development procedure finding optimal size integration curve used In case estimation, analysis momentum changes has been The deficit, within given control volume containing analysed aerofoil, determined related reaction Additionally, pressure reconstruction data, which enabled application small surfaces kept estimation error at satisfactorily low level, was introduced. tested verified reference computational dynamics simulation applied further wind tunnel data. A standard NACA0012 aerofoil two regimes (Re= $$0.7\times 10^5$$ 0.7 × 10 5 Re= $$1.4\times 1.4 ). Lift coefficient characteristics function angle attack obtained. exceptional agreement between numerical attained (relative differences no larger than 5%). acceptable level similarity observed (max. discrepancies below 20%). Graphic abstract