The joint project „Computer Aided Simulation of tightly inter-meshing, co-rotating twin screw extruders“ has been in existence since 1992. Today, SIGMA allows the user to evaluate processes of co-rotating twin screw extruders before they are performed in the lab. Hence, the use of SIGMA results in saving both money and time and with that in shorter development and optimization times.

The reference manual at hand tends to impart theoretical basics that are the basis for SIGMA. However, this manual is only in the position to impart basics; a comprehensive list of references is given for more detailed information. The manual at hand should impart the knowledge, which is required for both the correct use of the software and the critical evaluation of processes. More detailed information regarding to the programming are not included in the reference manual, due to that the programming details are described in the user manual.

We appreciate the support of all our project partners! Without their support SIGMA could not exist.

The Software-Engineering Team SIGMA

Paderborn, March 2026

• Material Parameters
• Geometry of Tightly Intermeshing, Co-rotating Twin Screw Extruders
• Melting Calculation
• Melt Conveying
• Melt Temperature
• Torque and Power Consumption
• Residence Time Distribution
• Mixing in Co-rotating Twin Screw Extruders
• Degree of Dispersion
• Scale-up
• Fiber Fracture Calculation
• Die
• Barrel Heat Flows
• Calculation of the degassing surface
• Cost Calculation
• Strand Cooling
• Nomenclature
• References