Dynamic Mesh: Movement of a Golf Ball due to an Impact

This project simulates the motion of a golf ball driven by an impact force of 200 N applied at an angle of 30°, determining the ball's flight path with ANSYS Fluent. The central theme of the study is dynamic mesh modelling: rather than holding the ball fixed in a steady stream, the simulation lets the ball move freely through the domain in response to the aerodynamic and impact forces acting on it, and the computational mesh deforms and regenerates to follow that motion. The model is three-dimensional, with the golf ball placed inside a surrounding flow domain created in Design Modeler.

Meshing was carried out in ICEM, producing a grid of more than 945,765 cells. Because the ball moves and its trajectory evolves in time, a transient solver is used so that the displacement of the ball can be tracked as a function of time.

Dynamic mesh is what makes the free motion possible, and it is the core of the methodology. As the ball travels, the cells around it stretch and distort, so their quality degrades over time. To keep the solution stable and accurate, the smoothing and remeshing sub-models are enabled: smoothing adjusts node positions to relieve distortion, while remeshing rebuilds cells locally whenever their quality falls below acceptable limits. The six-degrees-of-freedom (6-DOF) solver is used to govern the ball's movement, allowing all possible translational and rotational motions to be computed from the forces acting on it — here initiated by the 200 N impact. For the turbulence field, the SST k-ω model is applied, chosen for its strong performance both near the ball's surface and in the surrounding free stream.

After solving, the simulation yields two- and three-dimensional contours of pressure and velocity at successive flow times, capturing how the flow field evolves as the ball moves. The pressure contours show a region of elevated pressure at the front of the ball — the stagnation point where the flow is brought to rest against the surface — and a region of reduced pressure at the rear, marking the wake where the flow separates from the ball. As a study in dynamic mesh modelling, the project demonstrates how a moving-mesh approach combined with 6-DOF motion, smoothing and remeshing can capture the genuinely free flight of a body through a fluid and resolve the time-dependent aerodynamic forces that shape its trajectory.