Master's Thesis Frederik Stute
CFD-Simulation af a novel Fan-Attenuator-CombinationCopyright: EBC
In this paper, the losses at the outlet region of a centrifugal fan are investigated via measurements and CFD. A cuboid-shaped body is mounted downstream to the fan, serving as a ’pressure regain unit’ (PRU) and the performance is evaluated. Preliminary experiments are conducted with several PRU geometry-variations. An increase in static pressure as well as efficiency is observed. Subsequently, a numerical analysis is performed with parametrization and optimization, to determine design recommendations for the PRU. An optimized geometry is derived, leading to higher pressure rise at all operating points. The flow characteristics inside the duct are analyzed. A recirculation
area downstream to the fan in the empty duct can be identified as the main difference to the flow with installed PRU. A higher turbulence induces pressure losses, which can be reduced by the PRU. Both experimental and numerical data show an energy-saving potential in optimizing the fan-outlet area.