Hybrid Multizonal gPROMS-CFD

High-precision multizonal gPROMS models with automated CFD coupling

PSE's Hybrid Multizonal gPROMS-CFD (Hybrid Multizonal) software is a unique and powerful tool that enables multizonal models in gPROMS to make use of computational fluid dynamics (CFD) models for the prediction of the network connectivity and the inter-zonal flowrates.

Multizonal (or multicompartment) models provide an accurate way of modelling the effects of non-ideal mixing in industrial-scale process equipment, by representing them as networks of well-mixed zones.

However, in the past, the wide application of such models has been limited by the difficulty of establishing the zone connectivity and calculating inter-zonal flowrates.

Hybrid Multizonal

combines multizonal (multi-compartment) models in gPROMS with CFD
offers unprecedented modelling accuracy for optimisation of design and operations
addresses traditionally "difficult" processes, including crystallisation, polymerisation, and fluidised-bed reactions
allows solution of both steady-state and dynamic simulation problems within reasonable computational time
delivers new value from both CFD and process modelling investment via model re-use.

In the past, creating such links has been a time-consuming and error-prone process.

With Hybrid Multizonal, all the user has to do is provide a single gPROMS model (of any level of complexity) of a well-mixed zone, and specify the number of zones to be considered and the approximate (x,y,z) co-ordinates of their centres in the CFD model. Hybrid Multizonal does the rest automatically.

How the gPROMS Hybrid Multizonal CFD tool works

Hybrid Multizonal uses the specified (x,y,z) co-ordinates to group the cells in the CFD model into a number of zones of irregular geometry.

This information is used to automatically create a multizonal model in gPROMS, by connecting multiple instances of a gPROMS model for a single well-mixed zone.

On execution, gPROMS reads initial inter-zone mass flowrates from the CFD model, performs the internal gPROMS calculations for each zone, and returns the zonal viscosities and densities to the CFD model, which then re-computes the mass flowrates.

Iteration between the two models (typically only 1 -3 cycles) proceeds until the returned values are within tolerance.

If necessary, the CFD model can also return zone volume-averaged hydrodynamic quantities (e.g. turbulent energy dissipation rate), which may affect some of the physical phenomena represented within the gPROMS zone model (e.g. the rate of nucleation in crystallisation models).

PSE provides the Advanced Model Library for Solution Crystallisation (AML:SC) for sophisticated zone models of crystallisation process. Similar models for reaction and polymerisation can be supplied under the ModelCare programme

PSE provides the Advanced Model Library for Solution Crystallisation (AML:SC) for sophisticated zone models of crystallisation processes. Similar reaction and polymerisation models can be supplied under PSE's ModelCare programme.

Using the Hybrid Multizonal gPROMS-CFD software - a simple step-by-step guide

The typical workflow for hybrid multizonal gPROMS-CFD modelling involves the following steps:

A. Prepare the CFD zone information

Step 1: Prepare a CFD model of the equipment of interest, incorporating total mass and momentum balances only

Hybrid image

Step 2 : Perform a preliminary CFD calculation using nominal values of viscosity and density

Step 3: Inspect the solution and identify approximately well-mixed zones

Identify well-mixed zones

Step 4:Specify the number of zones and the (x,y,z) co-ordinates of the centre of each zone in a simple text file

Step 5: Run a utility that identifies the cells belonging to each zone, the volume of each zone, and the zone connectivity

Prepare the well-mixed zone model

B. Prepare the gPROMS models

Step 6: Making use of the gPROMS ModelBuilder, prepare a gPROMS model of a single well-mixed zone

C. Execute the combined simulation

Step 7: Execute a gPROMS simulation of the Multizonal model. gPROMS automatically creates the zone flowsheet

Step 8: View the results of the calculation using gPROMS' standard facilities

Licensing, supported platforms and pre-requisites

Pre-requisites are:

gPROMS ModelBuilder for Linux
Fluent® version 6.1.22 for Linux or later

The Hybrid Multizonal gPROMS-CFD software is licensed as an option under the gPROMS ModelBuilder. The licence includes the utility for the automatic construction of the zone network, a Foreign Object for gPROMS-CFD communication during execution, and a self-configuring gPROMS multizonal network model.

See supported platforms for the latest details on supported platforms.

Available