DPM: Color Spraying on the Wall with Conical Injection

Color Spraying on a Wall with Conical Injection — ANSYS Fluent CFD Simulation

Description

This project simulates color (paint) spraying onto a wall using a conical injection in ANSYS Fluent. The discrete phase is modeled with a one-way coupled DPM approach, in which the continuous phase influences the particles but the particles do not feed back on the flow. The injection is of the cone type, with a particle velocity of 10 m/s and a cone angle of 30 degrees.

Geometry & Mesh

The 3D geometry was created in SpaceClaim. The computational domain is 3 m long, 3 m wide, and 4 m high. The mesh was generated in ANSYS Meshing using an unstructured grid, with a total of 254,934 cells.

Several assumptions underpin the simulation: the solver is pressure-based, the simulation is unsteady (time-dependent), and the effect of gravity is neglected.

Methodology

The problem setup is summarized below:

Viscous model — laminar

Discrete phase — enabled, with unsteady particle tracking; the injected material is the color spray, the particle type is inert, and the injection type is a cone

Boundary conditions — the side wall and back wall are stationary, with the discrete phase condition set to escape; the top wall is stationary, with the discrete phase condition set to trap

Solution methods — SIMPLE pressure-velocity coupling; second-order discretization for pressure, second-order upwind for momentum, and first-order upwind for the modified turbulent viscosity

Initialization — standard method

Conclusion

In this simulation, the spray paint deposited on the wall is modeled using an injector that introduces the particles in a conical pattern. The cone angle governs the spread and range of motion of the particles, determining how they disperse from the nozzle and where they ultimately strike the wall — with the trap condition capturing the particles that reach the target surface and the escape condition allowing them to exit elsewhere in the domain.