Helicopter

Description

This project simulates rotating helicopter rotor blades using the Mesh Motion technique in a transient formulation. A helicopter stays aloft by forcing a large mass of air downward through its rotating blades, generating an equal and opposite upward force — by aerodynamically shaping the blades and spinning them, the rotor raises the air pressure beneath the wing and creates lift. This project models that rotating rotor to quantify the net upward force, blade tip speed, and Tip Speed Ratio.

Methodology

The 3-D rotor and surrounding domain are designed in Design Modeler and meshed in ANSYS Meshing with roughly 937,677 elements. The Mesh Motion method is used to simulate continuous blade rotation at 1250 rpm about the Y-axis, requiring a transient solver to capture the rotating motion over time. The RNG k-ε turbulence model is applied to resolve the rotating flow field generated by the spinning blades.

Analysis

Post-processing includes velocity, pressure, and turbulent viscosity contours along with streamlines, revealing the swirling air motion induced by the rotating blades. Key performance metrics extracted from the simulation include a pressure difference across the rotor of 5 Pa, a maximum domain air velocity of 2 m/s, and a blade tip velocity of 1.96 m/s. These results illustrate how the rotor generates the pressure difference responsible for lift, and establish Mesh Motion as a core technique applicable to any continuously rotating machinery analyzed in transient mode — helicopter rotors, propellers, wind turbines, and mixers alike.