Chemical: Bubble Trap

A bubble trap is a deceptively simple device that solves an important problem in chemical and process engineering: removing unwanted gas bubbles from a liquid stream. It works purely on buoyancy — when bubble-laden fluid enters the trap, the chamber slows the flow down, and the gas, being far less dense than the liquid, rises and separates out so that clean liquid can leave from below. In this project, you'll use ANSYS Fluent to simulate that separation process and watch the trap do its job in real time.

The model is built in two dimensions in SpaceClaim, with a mixture of water and bubbles entering through a side wall and a lower outlet that allows purified water to exit. The geometry is meshed in ANSYS Meshing with a total of roughly 32,000 cells. Because the device relies on the density difference between the two phases, the Volume of Fluid (VOF) multiphase model is used to track the air–water interface, and gravity is applied in the Y direction to drive the buoyant separation. A laminar model is used, and the simulation is run as unsteady so that the entire process of bubbles entering and being trapped can be observed as it develops.

From the results, you'll follow the full sequence: the trap begins filled with water, the incoming mixture introduces bubbles, and the lighter gas phase rises to the surface where it escapes through the top outlet, while clean water leaves through the bottom — exactly the behavior a bubble trap is designed to produce. A transient animation captures this separation as it unfolds.

By the end of this project, you'll be able to set up an unsteady two-phase VOF simulation in ANSYS Fluent, model buoyancy-driven phase separation, and interpret transient results to evaluate how effectively a gas–liquid separation device performs.