Pressure velocity coupling in a subsonic round jet

An experimental investigation involving simultaneous measurements of the ra dial distribution of velocity within the shear layer of a jet and the longi tudinal distribution of pressure surrounding a jet is performed. The use of two statistical approaches (proper orthogonal decomposition, POD and linea r stochastic estimation, LSE) permits the analysis, in terms of vortical st ructures, of the pressure fluctuations surrounding the jet. These structure s are found to be responsible for the far-held noise emission. This method thus seems promising for providing a "structural model" of the turbulent fl ow field. (C) 2000 Elsevier Science Inc. All rights reserved.