Abstract
Today, much of the current e ort in combustion noise is the development of e cient numerical tools to calculate the noise radiated by ames. Although unsteady CFD methods such as LES or DNS can directly provide the acoustic eld radiated by noise sources, this evaluation is limited to small domains due to high computational costs. Hybrid methods have been developed to overcome this limitation. In these schemes, the noise sources are decoupled from the radiated sound. The sources are still calculated by DNS or LES codes whereas the radiated sound is evaluated by acoustic codes using an acoustic analogy. In the present paper the assessment of combustion noise is conducted by both direct (LES) and hybrid computations in a premixed swirled combustor. Some comparisons of the sound pressure levels resulting from both approaches are shown, and the main di erences between the two methods are explained.