Sea Robot Motion Immersed in Water (Dynamic Mesh) — ANSYS Fluent CFD SimulationDescriptionThis project presents a CFD simulation of a sea robot moving through water using the Dynamic Mesh technique — the essential method for problems where a body physically moves through the fluid domain and the computational cells must change shape and position over time. In this project, the robot (modeled as a cube) starts on one side of the domain and travels toward the inlet against an oncoming water stream, letting you study the pressure buildup ahead of it and the wake region trailing behind. As the opening project of the Dynamic Mesh: Beginner CFD Training Package, it introduces the dynamic-mesh method in its most fundamental form — a body in prescribed translation through a fluid — establishing the workflow the later valve, piston, and turbine cases build on.MethodologyThe 2D moving-body domain is designed in Design Modeler and meshed in ANSYS Meshing with roughly 30,010 elements. Because the location and shape of the computational cells change as the body moves, a Dynamic Mesh is mandatory, and a transient solver is required. Smoothing and remeshing work together to maintain high-quality elements as the body advances, preventing the mesh degradation that causes solver errors, with the mesh regenerated at a remeshing interval of every 50 iterations. A prescribed velocity profile is imposed on the moving body — 3 m/s in the X-direction over 0–3 seconds — while the surrounding flow is set up with an inlet water velocity of 1.5 m/s using the standard k-ε turbulence model.AnalysisPost-processing produces velocity, pressure, and turbulent-viscosity contours along with streamlines, revealing the elevated stagnation pressure ahead of the robot and the wake region trailing behind it. From these results you can study how the moving body loads the surrounding water and how its wake develops over time. Dynamic Mesh is the gateway to simulating real motion — submarines, AUVs, valves, pistons, projectiles, and store separation — and mastering smoothing and remeshing here equips you for an entire class of moving-body CFD problems. By the end of this project, you'll be able to set up a transient dynamic-mesh simulation, configure smoothing and remeshing to preserve mesh quality, prescribe the motion of a body through a fluid, and interpret the pressure and wake fields it produces.

Movement of Golf Ball, Impact (Dynamic Mesh) — ANSYS Fluent CFD SimulationDescriptionThis 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 is dynamic mesh modeling: 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. Within the Dynamic Mesh: Beginner CFD Training Package, this project builds on the basic prescribed-motion case by letting the body's trajectory be computed from the forces acting on it, introducing free flight through a fluid.MethodologyThe 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 governs 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.AnalysisAfter 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. By the end of this project, you'll be able to set up a dynamic-mesh simulation with 6-DOF motion, configure smoothing and remeshing to preserve mesh quality as a body moves, apply the SST k-ω model for external aerodynamics, and interpret the time-dependent pressure and velocity fields that shape a body's free flight through a fluid.

Bullet (HPBT) Movement (Dynamic Mesh) — ANSYS Fluent CFD SimulationDescriptionThis project simulates the movement of a Hollow Point Boat Tail (HPBT) bullet using dynamic mesh in ANSYS Fluent, exploring high-speed projectile dynamics. As the bullet travels at supersonic speed, it forms shock waves that govern its aerodynamic performance, and capturing this means letting the bullet move freely through the domain while the mesh deforms and regenerates to follow it. Because the flow is supersonic and compressible, the case also brings in the density-based solver and the shock physics that define high-speed aerodynamics. Within the Dynamic Mesh: Beginner CFD Training Package, this project combines moving-body dynamic mesh with compressible supersonic flow, adding shock-wave physics to the moving-body cases before it.MethodologyThe optimized 2D HPBT bullet geometry is created in ANSYS Design Modeler and meshed in ANSYS Meshing with an unstructured grid of 13,040 elements suited to dynamic remeshing. A density-based solver is set up for the compressible, transient flow, and the dynamic mesh model is configured for the bullet's movement at Mach 2.531, with ideal-gas properties assigned to the air to model the compressibility effects. As the bullet moves, the dynamic mesh deforms and regenerates to follow it, keeping the solution valid throughout the motion.AnalysisPost-processing extracts pressure, temperature, and velocity contours, revealing the supersonic flow around the moving bullet and the formation and propagation of the shock waves behind it. The mesh deformation and regeneration are evaluated to confirm the dynamic-mesh approach captures the transient flow correctly, and the compressibility effects are assessed to show why a density-based solver is essential at supersonic speed. From these results you can understand how the shock structure shapes the bullet's aerodynamic performance. By the end of this project, you'll be able to set up a dynamic-mesh simulation coupled with a density-based compressible solver, model a projectile moving at supersonic speed, and interpret the shock waves and pressure fields that govern high-speed projectile aerodynamics.

This project investigates the pigging process in pipeline transportation using ANSYS Fluent. Pigging refers to the use of inspection devices, commonly known as pigs or scrapers, to perform maintenance and cleaning operations inside large-diameter pipes. In this simulation, the pig begins moving while the outlet valve remains closed, with the domain initially filled with air. The analysis focuses on the pressure distribution on the pig's surface and along the central plane of the pipe, with particular attention to the junction where two pipe sections meet, since this region is critical from a pressure standpoint.The geometry was created in SpaceClaim, and the mesh was generated in ANSYS Meshing using tetrahedral elements, chosen for their compatibility with the deformation and remeshing required by the pig's motion. The final mesh contains 659,988 volume cells and meets the quality requirements for the simulation.MethodologyThe motion of the pig through the pipeline is captured using the Dynamic Mesh method, with the Remeshing and Smoothing sub-models handling the deformation and regeneration of mesh elements as the device advances.ResultsThe simulation provides the static pressure distribution on the pig's surface, with clear variations visible from different viewpoints along the pipeline. An animation was also generated, illustrating the pig's continuous movement from the start of the simulation until it approaches the outlet.For pipelines containing fluids such as water or oil rather than air, the model can be adapted to represent these conditions, allowing the cleaning process to be evaluated under more realistic operating scenarios.

Cylinder Piston Motion (Dynamic Mesh) — ANSYS Fluent CFD SimulationDescriptionThis project simulates the motion of a four-stroke engine's cylinder-piston system using ANSYS Fluent's Dynamic Mesh capabilities. Inside an internal combustion engine, the piston moves up and down through four stages — intake, compression, power, and exhaust — while the valves open and close in sequence, and the mesh must continuously deform and regenerate to follow that reciprocating motion. This project captures the complete cycle: the piston descending and the valve opening on the intake stroke, the flow compressing as the piston ascends, the piston reaching top dead center at the power stroke, and the exhaust valve opening as the piston descends again. Within the Dynamic Mesh: Beginner CFD Training Package, this project introduces classic reciprocating in-cylinder motion — the workhorse dynamic-mesh application at the heart of engine simulation.MethodologyThe geometry is created in Design Modeler and meshed in ANSYS Meshing. The Dynamic Mesh model is applied through the In-Cylinder option for the piston motion, defining the key parameters — crank radius, connecting-rod length, and piston stroke cutoff — with the full-piston function driving the boundary movement. Rigid body motion is set up for the piston surface and valves, profiles are used to describe the valve-lift changes, and deforming mesh zones and stationary options are assigned appropriately. The reciprocating motions are defined with time-dependent flow behavior, and a transient solver with suitable settings resolves the evolving in-cylinder flow.AnalysisPost-processing focuses on the pressure and velocity contours through the engine cycle, along with animations of the mesh changes and flow behavior that verify the correct operation of the cylinder-piston system. From these results you can follow how the flow is drawn in, compressed, and expelled across the four strokes, and confirm the dynamic mesh handles the piston and valve motion correctly. By the end of this project, you'll be able to set up a Dynamic Mesh simulation using the In-Cylinder option, define reciprocating piston and valve motion through crank parameters and lift profiles, apply deforming and rigid-body mesh zones, and interpret the time-dependent pressure and velocity fields of a four-stroke engine cycle.

Check Valve (Dynamic Mesh) — ANSYS Fluent CFD SimulationDescriptionThis project simulates the flow behavior of a check valve using the Dynamic Mesh capabilities of ANSYS Fluent. A check valve allows flow in one direction only, opening and closing in response to the fluid itself — a coupled interaction where the flow drives the valve's motion and the valve's position in turn shapes the flow. Capturing this means letting the valve move under the forces acting on it while the mesh deforms to follow. Within the Dynamic Mesh: Beginner CFD Training Package, this project introduces flow-driven valve motion, where the moving part responds to the flow rather than following a prescribed path, and adds multiphase flow to the dynamic-mesh toolkit.MethodologyThe geometry — a pipe fitted with a check valve — is created in Design Modeler and meshed in ANSYS Meshing. The dynamic mesh implementation applies the Six Degrees of Freedom (6-DOF) solver to compute the valve's rotational motion from the fluid forces, with deforming mesh zones that adapt as the valve moves and rigid body motion defined for the valve itself. The simulation is enriched with several advanced techniques: a multiphase Volume of Fluid (VOF) model for water and air, time-dependent flow behavior through a transient solver, and Execute Commands to control the inflow conditions. Together these capture the coupled fluid–valve interaction that governs unidirectional flow through the valve.AnalysisPost-processing focuses on the water mass-fraction contours, along with animations of the valve movement and flow behavior that verify the check valve operates correctly — opening to allow forward flow and closing to prevent reverse flow. From these results you can study how the flow drives the valve's motion, how the valve regulates the flow direction, and how the two phases move through the system. By the end of this project, you'll be able to set up a dynamic-mesh simulation with the 6-DOF solver for flow-driven valve motion, couple it with a VOF multiphase model, use Execute Commands to control inflow, and interpret the results that confirm correct check-valve operation.

DescriptionThis project simulates a non-return (check) valve, a device that allows flow in one direction while blocking reverse flow, using ANSYS Fluent. Such valves are needed wherever downstream pressure can rise above inlet pressure, since without them the flow would push backward through the system and potentially damage it. The valve motion is captured through dynamic mesh with one-degree-of-freedom rotation, letting the valve flap swing open and closed in response to the flow rather than following a prescribed motion. The inlet velocity is driven by a UDF that ramps up to 1 m/s over the first 0.4 seconds, then drops to a near-zero value of 0.000001 m/s afterward, simulating an abrupt loss of driving flow. The geometry is a 26 cm × 5 cm two-dimensional domain built in SpaceClaim and meshed in ANSYS Meshing with an unstructured grid of 61,580 elements.MethodologyThe valve dynamics are handled through the Six DOF solver with only one rotational degree of freedom enabled, and a spring stiffness of 1 N·m/rad is added to help drive the valve closed once the flow subsides. Turbulence is modeled with SST k-omega, and the solution uses a transient, pressure-based solver with gravity neglected. The inlet is a velocity-inlet driven by the UDF profile, the outlet is a pressure-outlet at 0 Pa gauge, and all other walls are stationary. Pressure-velocity coupling uses SIMPLE, with second-order discretization for pressure and momentum, and first-order upwind for turbulent kinetic energy and dissipation rate; initialization is standard.AnalysisThe results show the valve opening for the first 0.4 seconds while the high-velocity, high-kinetic-energy inflow pushes it open, then beginning to close as soon as the flow velocity drops toward zero. The spring force reinforces this closing motion, accelerating valve closure and ensuring the flow cannot slip back through the inlet once the driving pressure is gone. The reported UDF velocity-versus-time profile and the force-on-valve-versus-time plot together show this open/close cycle directly, tying the valve's mechanical response to the imposed flow transient.

CG-Motion Macro, UDF, Reciprocating Motion — ANSYS Fluent CFD SimulationDescriptionThis project simulates a cubic object undergoing reciprocating motion within a fluid domain using the CG-MOTION macro and the dynamic mesh capabilities of ANSYS Fluent. Where earlier dynamic-mesh cases prescribe motion through built-in options, this project shows how to define the motion yourself through a User-Defined Function (UDF) — the programmable, fully flexible way to drive a moving boundary. It demonstrates the power of UDFs for capturing complex object movements and their effect on the surrounding fluid. Within the Dynamic Mesh: Beginner CFD Training Package, this project introduces UDF-driven motion, giving you direct control over how a body moves rather than relying on a preset motion option.MethodologyThe work brings together three main components: 3D geometry modeling in Design Modeler, an unstructured mesh of 143,423 cells generated in ANSYS Meshing, and a CFD simulation in ANSYS Fluent driven by a custom UDF that prescribes the object's motion. The methodology relies on the Dynamic Mesh model to simulate the movement of a rigid body within the fluid domain: as the object reciprocates, the dynamic mesh deforms to accommodate its motion — the essential mechanism that allows a moving boundary to be represented. The moving object is defined as a rigid body, and its translational motion is imposed through a custom implementation of the DEFINE_CG_MOTION macro. The module guides you through the full UDF process — writing a custom velocity function for the reciprocating motion, implementing it within the DEFINE_CG_MOTION macro, compiling and loading the UDF into ANSYS Fluent, and configuring the Dynamic Mesh model to use this custom motion function.AnalysisOnce the simulation has run, you analyze how effectively the custom UDF captures the prescribed motion — examining time-dependent snapshots of the geometry, the path traced by the moving object, and the variation of its velocity and position over time. From these results you can confirm the UDF drives the motion correctly and see how the reciprocating body affects the surrounding fluid. Custom motion modeling of this kind brings greater flexibility in simulating a wide range of motion patterns, improved accuracy in fluid-structure interaction, and the ability to represent complex mechanical systems in CFD — with applications from piston engines to industrial mixing. By the end of this project, you'll be able to write and compile a DEFINE_CG_MOTION UDF, drive a rigid body's reciprocating motion through custom code, configure the Dynamic Mesh model to use it, and interpret the resulting motion and flow — a foundation for advanced work such as coupled FSI and multi-body motion.

DescriptionThis project uses ANSYS Fluent to simulate a Darrieus vertical axis wind turbine (VAWT) with the Dynamic Mesh 6DOF method, a core application of the dynamic mesh module for modeling rotation driven by fluid forces rather than a prescribed motion. The turbine's curved blades keep them in tension at high rotational speeds, and a helical blade arrangement helps distribute torque evenly across the revolution, reducing pulsation. In this case, a 6-blade Darrieus turbine is exposed to wind at 23 m/s, with turbine rotation resolved based on the moment generated by the flow itself.MethodologyThe 3D domain is built in DesignModeler, consisting of a flow domain and a body-of-influence region around the turbine, with a velocity inlet, pressure outlet, and ground wall boundary. The domain is meshed in ANSYS Meshing using an unstructured grid of 2,966,928 elements and 720,300 nodes. Turbine rotation is captured using the Dynamic Mesh 6DOF method, allowing the blades to rotate in response to the aerodynamic moment acting on them, rather than a fixed prescribed rotational speed.ConclusionResults show clear turbine rotation driven by the flow, with velocity contours revealing vortices — including Von Kármán vortex shedding — generated by the interaction between the flow and the rotating blades. Pressure contours show the highest pressure gradient at the blade leading edge, consistent with the flow velocity dropping to zero at that point. Streamline vectors resolve the wake region flow quality, a key challenge in this type of aerodynamic simulation, while the turbulence contour accurately captures the resulting turbulent structures.

DescriptionThis project uses ANSYS Fluent to simulate a Darrieus-type vertical axis water turbine (VAWT) submerged in flowing water, applying the Dynamic Mesh method to capture rotation driven by the surrounding flow — a relevant application in marine renewable energy and hydrokinetic power generation. Unlike wind-based VAWTs, this turbine extracts kinetic energy directly from water flow, with its rotational axis perpendicular to the flow direction. The three-bladed turbine rotates freely in response to the fluid forces acting on it, allowing its performance under water flow conditions to be evaluated.MethodologyThe 3D geometry is built in DesignModeler, consisting of a large computational domain containing a three-bladed Darrieus turbine (0.5 m blade height), with the turbine center positioned 3 m from the inlet, 10 m from the outlet, and 0.75 m from the top and bottom domain surfaces. The domain is meshed in ANSYS Meshing using a hybrid grid — unstructured around the turbine body and structured elsewhere — totaling 7,422,668 elements.Water enters the domain at 1 m/s along the horizontal axis, with a pressure outlet at atmospheric conditions and symmetry conditions applied to the top and lateral surfaces. The turbine's rotation is captured using the Dynamic Mesh model, with a cylindrical sub-region isolating the turbine blades as rigid bodies. Rotational motion is defined with one degree of freedom (1-DOF), using a blade mass of 1 kg and moment of inertia of 3.09 kg·m². The simulation is run transient, over 50 seconds with a 0.05 second time step, consistent with the dynamic mesh approach.ConclusionResults include 2D contours of velocity, pressure, and turbulent kinetic energy, along with pathlines and velocity vectors on a plane through the turbine center. Turbine torque and other performance characteristics are also analyzed, providing insight into the turbine's power extraction behavior — relevant to marine hydrokinetic energy system design and evaluation.