Fan Stage: Axial Flow

Fan Stage (Axial Flow) Aerodynamic Performance — ANSYS Fluent CFD Simulation

Description

This project presents a CFD simulation of an axial flow fan stage — a rotor–stator assembly that produces steady airflow for industrial applications such as cooling freshly painted body parts. The rotor's spinning blades accelerate the incoming air and induce swirl, and the stationary stator blades then straighten the flow so it exits roughly normal to the outlet. This is a classic, approachable introduction to turbomachinery CFD, and in this project you'll model both the rotating and stationary zones and evaluate the fan stage's aerodynamic performance. As the opening project of the Fan: Beginner CFD Training Package, it introduces the fan itself — its aerodynamics and the MRF rotating-zone method — establishing the foundation the fan-driven HVAC and ventilation cases build on.

Methodology

The 3D rotor–stator geometry is designed in Design Modeler with separate rotating and stationary zones defined, then meshed in ANSYS Meshing with roughly 244,675 cells. A periodic boundary condition is used to model only a slice of the fan rather than the full annulus, dramatically reducing computational cost. The MRF (Moving Reference Frame) method is set up to simulate the rotor's rotation at 1800 rpm while keeping the stator fixed — a steady-state approach that avoids the expense of a fully transient moving mesh — and the standard k-ε turbulence model is applied to the rotating flow field.

Analysis

Post-processing produces 2D and 3D pressure, velocity, streamline, and velocity-vector results, clearly visualizing the swirl induced by the rotor and its correction by the stator. From these you calculate the key turbomachinery performance metrics: a rotor tip linear velocity of about 31 m/s, a Tip Speed Ratio (TSR) of 4, and an outlet airflow rate of 16.14 lit/s. Fans, compressors, pumps, and turbines all rely on rotor–stator interaction, and the MRF + periodic-boundary workflow learned here is the standard, cost-efficient approach to turbomachinery analysis — directly transferable to blowers, axial compressors, and ventilation fans. By the end of this project, you'll be able to build a rotor–stator geometry with distinct motion zones, apply periodic boundaries to model a representative slice, set up the MRF method for a rotating fan, and post-process the flow to compute the performance metrics that define fan behavior.