The authors investigate the far-field noise emissions of a datum fan blade fitted with tip end-plate geometries, originally designed to\r\ncontrol the leakage vortex swirl level. The end-plate geometries influence the tip-leakage flow, vortex formation, and swirl level. In\r\ndoing so, the end-plate geometries influence the sound-power levels. After an evaluation of fan rotors� aerodynamic performance,\r\nthe study compares the rotors� far-field noise signature characterised in terms of sound-power and pressure-level spectra to enable\r\nand assess the end-plate acoustic pay-off. The investigation attempts to establish a cause-and-effect relationship between the tipflow\r\ndynamics and the radiated sound fields, exploring the diverse directivity patterns. The authors found a tonal reduction,\r\ndue to the enhanced blade-tip end-plates and clarified the relevance of the tip features influencing the radial distribution of the\r\nnoise sources using coherence analysis. The modified multiple-vortex breakdown end-plate design was effective in reducing the\r\nbroadband noise, giving an improvement in the frequency range of the turbulent noise.
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