Acoustic Properties of Porous Coatings for Hypersonic Boundary-Layer Control
نویسندگان
چکیده
AR = cavity aspect ratio a = speed of sound b = cavity half-width ~ C = dynamic compressibility c = phase speed cp = specific heat at constant pressure f = frequency H = cavity depth k = wave number m = propagation constant P = pressure Pr = Prandtl number R = reflection coefficient p = acoustic pressure pi = initial pulse amplitude Re = acoustic Reynolds number s = cavity spacing T = temperature t = time x = tangential direction y = normal direction Zc = characteristic impedance = absorption coefficient = specific heat ratio ent = entropy-layer thickness S = Stokes-layer thickness = angle of incidence of acoustic wave = wavelength of acoustic wave = viscosity = density ~ = dynamic density = pulse width = porosity ! = angular frequency
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