Dennis Román | Project Portfolio

CFD Lab

CFD Lab: Vertical Axis Wind Turbine (MRF Study)

Steady-state Moving Reference Frame CFD study of a 3-blade Darrieus VAWT, focused on mesh-interface setup, rotating-zone modeling, and wake behavior.

ANSYS FluentMRFMesh InterfacesPost-Processing
VAWT problem setup schematic

Problem setup: 3-blade Darrieus VAWT in uniform inflow.

Snapshot

  • Source basis: Cornell SimCafe VAWT Part 1 + AE 4801 lecture material
  • Modeling style: Steady-state MRF approximation (rotor spun at fixed RPM)
  • Turbine type: Lift-based Darrieus VAWT
  • Primary objective: Build a stable rotating-frame setup and interpret wake behavior

Problem specification

ParameterValue
Inflow velocity10 m/s
Angular velocity40 RPM
Rotor diameter12 cm
Blade count3 equally spaced blades
Chord length2 cm
Blade center radius0.04 m from hub center

Modeling approach

  • Used a Moving Reference Frame (MRF) formulation to simplify transient rotor motion into a steady approximation.
  • Defined rotating inner zone and stationary far-field zone with explicit angular velocity assignment.
  • Used non-conformal mesh interfaces across zone boundaries and set Fluent interfaces for information transfer.
  • Kept blade positions and hub-centered geometry consistent with lecture setup definitions.

Results and interpretation

  • Velocity contours show clear rotor interaction and an organized downstream wake.
  • Wake non-uniformity across azimuthal blade position appears in post-processed flow fields.
  • Turbulent kinetic energy contours show increased eddy activity in wake-dominated regions.
  • Outputs are consistent with expected behavior for a simplified steady MRF VAWT study.

Validation and reproducibility notes

  • Validation focus was trend-level consistency (wake shape, velocity deficit, TKE distribution) under fixed setup.
  • Setup assumptions are explicit: fixed RPM and frozen-flowframe approximation.
  • Mesh-interface naming and zone definitions are documented to support repeat runs and peer review.

Validation

  • Wake structure captured downstream of rotating blades

    pass

  • MRF setup uses fixed rotating-zone angular velocity

    pass

Reproducibility

  • Parameter-first problem definition

    Geometry and operating values documented before setup (V, RPM, D, chord, blade radius).

  • Interface and zone checklist

    Non-conformal interfaces and rotating/stationary zones explicitly defined.

  • Standard result package

    Velocity, wake, and turbulence fields captured in a repeatable post workflow.