Jet noise predictions by time marching of single-snapshot tomographic PIV fields

Autor: Daniele Ragni, Daniele Fiscaletti, Woutijn J. Baars
Rok vydání: 2022
Předmět:
Zdroj: Experiments in Fluids: experimental methods and their applications to fluid flow, 63(5)
ISSN: 1432-1114
0723-4864
Popis: Abstract This work combines the latest advancements in time marching of 3D vector fields from tomographic particle image velocimetry, with an adapted version of Lighthill’s formulation, for the prediction of far-field jet noise. Three-dimensional velocity vector fields of the jet flow are first reconstructed from a tomographic volume of 4$$\times$$ × 3$$\times$$ × 9.5 $$D_{j}^3$$ D j 3 , with $$D_{j}$$ D j = 5 cm being the jet-exit diameter. (The jet-exit Mach number $$M_{j}$$ M j ranges from 0.10 to 0.20.) The obtained vector fields are then used as input to a recently developed procedure for the time marching of the vorticity field, which relies upon the vortex-in-cell methodology. This yields time series of each three-dimensional velocity field, from which the far-field pressure is computed via Lilley’s acoustic analogy (through evaluation of the Lighthill’s stress tensor). It is shown that the estimate of the far-field noise spectrum compares well with the spectrum measured directly from a far-field microphone in the anechoic A-tunnel facility of TU Delft, in the Strouhal number range from approximately 1 to 12. Graphical Abstract
Databáze: OpenAIRE
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