Computational Investigation of Radial Impeller Design for Electric Pneumatic Propulsion

In the current study, simulations were made using Ansys Fluent to extend upon a previous study conducted by Luke Sadowksi in 2024 where he experimentally analyzed the performance of three radial impeller variants in an electrically driven compressor-nozzle pneumatic propulsion system (ED-CNPPS). The impeller variants each had a differing blade shape: Impeller 1 having uncurved circular blades, Impeller 2 having forward curved circular blades, and Impeller 3 having circular blades with edges normal to the tangent line of the impeller perimeter (BENTL). Using CAD models from the original experiment, simulations were run for all three variants at different angular velocities for the impeller. The performance of each variant was evaluated by taking the computed average exhaust velocity and mass flux at the nozzle to calculate the thrust produced by the system. To replicate the static conditions in Sadowski’s original experiment, a pressure inlet boundary condition was applied with 0 Pa as the gauge pressure. Additionally, simulations were run using a velocity inlet boundary condition to compare the performance of the three radial impellers under uniform initial air velocity conditions. The findings of this study differ significantly from original experimental results with Impeller 3 performing the worst and Impeller 2 performing the best under the 0 Pa boundary condition. The opposite was the case in the experimental investigation. However, under the uniform initial air velocity conditions, the results follow a trend more in line with the experimental results as Impeller 1 and Impeller 3 produced higher thrusts than Impeller 2.