The work objective is to evaluate how the geometric transfor-mations of the trailing edge of some airfoils affect the aerody-namic characteristics. Such transformations as the trailing edge thickening and rounding are considered. The performance of Wortmann FX 63-137, NACA 23024 и Clark Y is calculated. The effect of the trailing edge changes on their aerodynamic performance at Reynolds numbers from 200,000 to 1,000,000 is assessed. It is shown that the thickening of the trailing edge in-creases the drag coefficient up to some Reynolds number de-pendent on the airfoil, and thereafter it reduces. At that the in-crease of the lift coefficient is observed. The rounding of the trailing edge reduces both the lift and drag forces, and it can lead to the improvement of the airfoil lift-to-drag ratio for certain angles of attack. The data obtained can be used in the manufac-ture of blades with the profiles discussed.
airfoil, trailing edge transformations, aerodynamic parameters, lift coefficient, head drag coefficient.
В настоящее время для расчета аэродинамических характеристик лопастей используются элемент-но-импульсная теория и метод несущей линии. Такой подход требует знания безразмерного коэффициента подъемной силы и безразмерного коэффициента лобового сопротивления крыльевых профилей, используемых в сечениях лопасти. Данные коэффициенты зависят от угла атаки атаки и числа Рейнольдса набегающего на лопасть потока.
При производстве лопастей для достижения идеально острой задней кромки ее толщина зачастую уменьшает-ся путем шлифовки, что представляет собой дорогой и трудоемкий процесс. Это предопределяет важность получения данных для оценки целесообразности проведения процесса заострения задней кромки лопасти
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