Inlet Gap Influence on Low-Frequency Flow Unsteadiness in a Centrifugal Fan

In this study, unsteady low-frequency characteristics in a voluteless low-speed centrifugal fan operating at high mass flow rate are studied with improved delayed detached eddy simulation (IDDES). This study is motivated by recent finding that the non-uniformly distributed pressure inside type of could be alleviated improving gap geometry. The present results show velocity magnitudes have distinct low and regions. Intensive turbulent structures developed low-velocity regions swept downstream along intersection between blade shroud, on side blade. Eventually, turbulence gives rise to high-pressure region near blade’s trailing edge. behavior revolves around rotation axis. Additionally, its period 5% speed, based analysis time history evolution region. same frequency was also found previous experimental measurements. To authors’ knowledge, first trigger turbulence, i.e., local velocity, has been determined.