Centrifugal Pump

Description

This project models and analyzes a centrifugal pump in ANSYS Fluent to study its aerodynamic performance. The impeller and volute geometry were created in SpaceClaim/Design Modeler and simulated under steady-state conditions at 1500 RPM with an inlet velocity of 140 m/s. The aim was to evaluate the velocity distribution and pressure rise across the pump as the rotating impeller transfers energy to the working fluid.

Geometry & Mesh

The 3D centrifugal pump, including the impeller blades and volute casing, was meshed in ANSYS Meshing using about 2 million tetrahedral cells. The mesh was refined around the blade passages and the volute to accurately capture the turbulence and pressure gradients in these critical regions.

Methodology

The simulation used a pressure-based, steady-state solver with the k-ω SST turbulence model, which is well suited to rotating machinery. The impeller rotation is represented using the Multiple Reference Frame (MRF) approach, in which the impeller zone is assigned a rotating frame while the volute casing remains stationary — an efficient way to capture steady turbomachinery rotation without physically moving the mesh. The boundary conditions were a velocity inlet of 140 m/s and a pressure outlet, and the Coupled algorithm was used to ensure stable pressure-velocity convergence.

Conclusion

The results show strong acceleration of the flow through the impeller, with outlet velocities reaching about 300 m/s. The pressure field exhibits a clear rise from inlet to outlet, with high pressure on the pressure side of the blades and low pressure on the suction side. The flow pattern within the volute confirms efficient energy transfer from the impeller rotation to the fluid, validating both the design and the CFD setup.

Overall, the simulation reproduces the expected behavior of a centrifugal pump — converting mechanical rotational energy into increased fluid velocity and pressure — and demonstrates the effectiveness of the MRF approach for analyzing the steady rotating-impeller performance of turbomachinery.