Microfluidics Module Updates

For users of the Microfluidics Module, COMSOL Multiphysics® version 6.0 brings a new feature for porous slip wall treatment for the Brinkman Equations interface and a new tutorial model that uses topology optimization. Learn more about these updates below.

Porous Slip for the Brinkman Equations Interface

The boundary layer in flow in porous media may be very thin and impractical to resolve in a Brinkman equations model. The new Porous slip wall treatment feature allows you to account for walls without resolving the full flow profile in the boundary layer. Instead, a stress condition is applied at the surfaces, yielding decent accuracy in bulk flow by utilizing an asymptotic solution of the boundary layer velocity profile. The functionality is activated in the Brinkman Equations interface Settings window and is then used for the default wall condition. You can use this new feature in most problems involving subsurface flow described by the Brinkman equations and where the model domain is large.

A porous reactor model showing the flow and concentration in the Rainbow color table.
The flow and concentration field of a porous reactor model.

Two-Phase Flow in Porous Media

A new multiphysics interface combines the Brinkman Equations and the Level Set interfaces, and automatically adds a Two-Phase Flow, Level Set coupling node. It solves the conservation of momentum and a continuity of mass with the Brinkman equations. The interface between two immiscible fluids in porous media is tracked with the level-set function.

Resin showed in the Aurora Australis color table, injecting into an empty mold model.
Resin injection into an empty mold. The new interface is used to track the injection front. The mold contains one inlet and three outlets, and a porous block in the center, and it is initially filled with air.

Greatly Improved Handling of Porous Materials

Porous materials are now defined in the Phase-Specific Properties table in the Porous Material node. In addition, subnodes may be added for the solid and fluid features where several subnodes may be defined for each phase. This allows for the use of one and the same porous material for fluid flow, chemical species transport, and heat transfer without having to duplicate material properties and settings.

New Tutorial Model

COMSOL Multiphysics® version 6.0 brings one new tutorial model to the Microfluidics Module.

Optimization of a Tesla Microvalve with Transient Flow

A 2D plot of a Tesla microvalve model showing the flow in the Rainbow color table."
Results using topology optimization of a Tesla microvalve for an oscillating pressure drop. A Tesla microvalve inhibits backward flow using friction forces rather than moving parts. Therefore, the objective is to maximize the average flow rate.

Application Library Title:
Download from the Application Gallery