Nearfield acoustic holography (NAH) in a moving medium can be used to localize and quantify sound sources situated in a fluid flow. In most NAH applications the sound pressure is used as the input to the NAH method. However, locating microphones in the flow will cause additional noise sources due to their interaction with the flow. This will clearly affect the reconstruction results. An alternative acoustic input for performing NAH is the acoustic particle velocity which can be measured using optical methods, such as LDV. The main advantage of particle velocity measurements is that they are non-intrusive. This paper presents an alternative method that combines the equivalent source method and particle velocity measurements. One advantage of the equivalent source method is that it can be used for sources distributed over arbitrary geometries, such as cylinders and spheres. Furthermore, the method can be implemented in the space domain, and thus avoids the singular problem in the wave number domain, as discussed by, for example, Dupuis et al. In this paper numerical simulations are presented to examine the performance of the proposed method. It is shown that the method is accurate and robust over a wide range of flow velocities.
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