Digital Tools for Textile Production

Textile Industry: Simulation of the Spinning Process

News / September 26, 2025

Mechanical engineering is a cornerstone of the German economy and plays a crucial role in promoting innovation and technological development in many sectors. The textile industry in particular faces the challenge of continuously adapting to the demands of globalization, sustainability and the rapid progress of digitalization. Digital simulations are indispensable tools for optimizing production processes, testing design alternatives and increasing efficiency. With two software solutions developed at Fraunhofer ITWM, our researchers are creating added value for the clothing industry.

A central aim of VISPI (virtual spinning) is to increase the flexibility of textile production. The ability to react quickly to market changes is also crucial for this industry. Virtual spinning enables companies to test the impact of different process settings without having to create physical prototypes. »We want to help manufacturers speed up their product development and reduce costs at the same time,« explains Dr. Walter Arne, who is co-developing the software.

Tests Without Physical Prototypes

»VISPI« uses state-of-the-art digital technologies to virtually simulate the spinning process. This allows the properties of fibers to be digitally modeled and analyzed as early as the planning phase. The simulation of the spinning process also makes it possible to investigate the influence of various process parameters on the quality of the fibers. »Virtual simulation allows us to optimize the spinning process even before actual production begins,« says Arne. This approach can significantly shorten the time to market for new textile products and at the same time significantly improve the quality of existing spinning processes.

Software Tool »Cashocs« Enables Optimization of Spinnerets

In the manufacturing process of synthetic fibers, the polymer melt is pressed through fine nozzles, spun into fibers and then solidified by cold air flow. »VISPI« simulates from the spinneret to the first godet and also takes into account the supply of airflow to cool the fibers.

»At Fraunhofer ITWM, we do not only simulate various spinning processes, but were also recently able to integrate a new tool for optimizing the design of nozzles into our investigations,« reports Arne. This refers to the software cashocs, which was developed as part of his colleague Dr. Sebastian Blauth’s doctoral thesis. With »cashocs«, the nozzle itself, from which the fibers emerge, is optimized. To do this, the air flow around the fibers is simulated in detail and their arrangement is improved using mathematical optimization methods. »Uniform cooling of the fibers is important for product quality so that all filaments have the most uniform properties possible,« explains Blauth

Optimization with »cashocs« creates lanes in the fiber arrangement, for example, through which the cooling air can also reach the rear filaments, which are often poorly cooled. The optimization changes the arrangement of the filaments so that they all receive the most effective cooling in the right place – the nozzles just have to be drilled in other positions for this. »Optimization with cashocs provides clear recommendations for action that are very easy to implement and have a major impact on the quality of the spinning process.«

Figure 1: Optimized Arrangement of Hole Positions — © Fraunhofer ITWM
An arrangement of hole positions before optimization.

Figure 2: Optimized Arrangement of Hole Positions — © Fraunhofer ITWM
An optimized arrangement of the hole positions improves the flow and thus significantly improves the cooling of the filaments.

News

Digital Tools for Textile Production

Textile Industry: Simulation of the Spinning Process

Tests Without Physical Prototypes

Software Tool »Cashocs« Enables Optimization of Spinnerets

More Information

Contact Press / Media

M.A. Eva Fröhlich

Contact Press / Media

Dr. Walter Arne

Contact Press / Media

Dr. Sebastian Blauth