PRESSURE DEPENDENCE OF TURBULENT JET NOISE
湍流喷注噪声的压力关系

Ever since the fifties, profound theoretical and experimental investigations were spent on the noise production of subsonic and supersonic jets, but little has been done on the turbulent noise of a choked jet. In a previous paper the authors derived the pressure dependence of the latter. In this paper it is shown that a slight modifica-tion of the formula in the above-mentioned paper will make it applicable to subsonic jets too, and an interpretation is obtained for turbulent jet noise in general. From this it is inferred that turbulent jet noise has its origin in the quadrapole radiation of turbulent eddies, the only difference in that, for a choked jet, the turbulence velocity further increases with the stagnation pressure, although the mean jet velocity does not. From this point of view, the rule of increase of the turbulent velocity with increasing stagnation pressure is predicted. This interpretation seems plausible and the noise relations thus derived agree with experiment.