Question

QUESTION 2: The distribution of surface velocity V over a thin, symmetric airfoil at a small angle of attack was obtained by the potential theory and is shown below, where U is the freestream velocity. Here, c is the chord length of the airfoil and x is the distance measured from the leading edge along the chord. X/C 0.0 0.1 0.2 0.3 0.4 0.6 0.8 1.0 1.29 V/U. (suction side) V/U. (pressure side) 0.00 0.00 1.28 1.05 1.29 1.13 1.16 1.24 1.16 1.14 1.08 0.99 0.95 0.82 0.82 a) Determine the minimum and maximum pressure coefficients (Cp) observed on the surface of the airfoil (suction side refers to top surface and pressure side refers to bottom surface) (2 points) b) Determine the lift coefficient (C) for the airfoil and its angle of attack. (3 points)

Answer 1

Answer Minimum pressure cocffecient Coming Como - Imox Ula Comin 1 - 1:29 c) max = 0 1:29 Comin 11 -0.429 Cpmin= -0.29 maximum pressure Coefficient Cpmax Cpmax = 1 Ucc mis Cpman - 1 Cpmore 1

o Ca e. į Cerrone - Cpupper 2 de 1 of 4 Cp. 4x ĆE Upper Upper, Uhower d. axi Va * [ (1:28-1:05) *0.1 + (1.29 - 1113)oxo a (1.29-1-16)x0.3 +(1.24-116) X0-4 +(1.14 - 1.08 ) x 0.6 t (0.99 -0.95) xo 8 t (0.82 -0.82) x 1 ] Cu = 0.194