4. Flow models

To better understand how micro-compounders work, and to help users optimize their operating conditions, it is useful to develop numerical flow models. This can be done at several levels, from highly simplified analytical approaches to 3D finite element calculations. In the following, we'll confine ourselves to simplified approaches, which are easier to use in practice. Once again, we illustrate the case of the ThermoFisher MiniLab, but the calculations are of course directly transposable to other geometries. The flow in the recirculation channel is common to both co- and counter-rotating configurations, but the flow in the screws differs depending on the configuration.