CFD Analysis of Discrete Phase Trap (TRAPPER) Particle Capture System

This study presents a computational fluid dynamics simulation of a particle trapping mechanism known as the discrete phase trap (TRAPPER), analyzing its efficiency and flow characteristics using ANSYS Fluent software.

Background and Significance

Discrete phase flows are increasingly prevalent across mechanical and engineering applications. As a subset of multiphase flow systems, dispersed multiphase flows—including bubble, droplet, and particle flows—require thorough understanding for optimal system design. In these systems, a carrier phase transports dispersed elements (particles, bubbles, or droplets) throughout the domain. CFD simulation provides critical insights for optimizing such systems.

Model Development

The computational model was developed using ANSYS design modeler and meshed with ANSYS meshing software. Key specifications included:

• Unstructured mesh configuration
• 420,485 elements for computational accuracy
• Inlet flow velocity of 5 m/s containing both continuous and dispersed phases

Simulation Methodology

The discrete phase model (DPM) was employed to capture particle behavior with several key physical phenomena incorporated:

• Saffman lift force to account for shear-induced lateral movement
• Pressure gradient forces affecting particle trajectories
• Gravitational effects, which play a central role in the trapping mechanism

Results and Analysis

The simulation produced comprehensive visualization outputs including:

• Pressure distribution contours
• Velocity fields
• Particle tracking pathlines

Analysis of the results demonstrated that the TRAPPER mechanism successfully captured 45.26% of the particles entering the system. The simulation also revealed significant interaction between the fluid and particle phases, with notable velocity increases observed in regions of higher particle concentration, confirming the importance of two-way coupling in accurately modeling such systems.

This analysis provides valuable design insights for improving particle separation efficiency in industrial applications utilizing gravity-based trapping mechanisms.