Three fans designed with forward, backward and unswept blades are analysed in the present work. The simulations are performed using Reynolds-Averaged Navier Stokes equations using k − ω SST turbulence closure model. The y + ∼1 is maintained on blade surfaces and computational domain is discretized using hybrid mesh. The predicted overall performances agree reasonably well with experiments and reproduce the observed hysteresis. The mean flow field before and after the fans also agree well with laser Doppler anemometry measurements.The farfield noise is predicted using Amiet's model for leading edge and trailing edge noise sources separately. The former is found dominant and the latter negligible. Secondary flow such as tip vortices are significantly contributing to the noise spectrum confirming that tip noise is a dominant noise source in such machines.
