At DOCAN, we are committed to helping clients make better engineering decisions by combining expertise with powerful tools. One of the most valuable parts of our partnership with SoftInWay is access to AxSTREAM’s rotor dynamics capabilities. These allow us to understand how rotating equipment behaves under real conditions, and to design systems that are both efficient and reliable. 

Rotor dynamics is often treated as a specialist area, but in practice it plays a central role in the performance of turbines, compressors, pumps and motors. Vibration, resonance and bearing issues can have major consequences if not properly addressed. By building rotor dynamics into our workflow from the start, we help clients avoid problems, reduce costs and extend equipment life. 

Why Rotor Dynamics Matters 

When equipment rotates at high speeds, the forces acting on the shaft and bearings become complex. Small changes in geometry, material properties or support conditions can lead to large differences in behaviour. Without careful analysis, this can result in excessive vibration, unstable operation, premature wear or even catastrophic failure. 

SoftInWay’s Series on Rotordynamics highlights the importance of this discipline. Rotor dynamics is not just about calculating critical speeds; it is about ensuring that the entire system – from shaft to bearings to supports – operates safely and predictably across all conditions.  

At DOCAN, we see this as a vital part of delivering robust designs. 

DOCAN’s Use of SoftInWay Tools 

Through our partnership with SoftInWay, DOCAN uses AxSTREAM to carry out detailed rotor dynamics analysis. This software integrates seamlessly with the wider suite of CFD and system simulation tools, allowing us to capture the interactions between fluid forces, structural response and dynamic behaviour. 

We typically apply the rotor dynamics module in several stages: 

• Concept design: At the earliest stage, we run screening analyses to identify potential issues and avoid layouts that could lead to resonance or instability. 

• Bearing and support modelling: We model stiffness, damping and compliance in bearings and supports, since these strongly influence rotor behaviour. 

• Lateral and torsional analysis: We examine both bending and twisting modes, ensuring that critical speeds are separated from operating ranges. 

• Transient simulation: We simulate start-up, shut-down and load changes to check how the rotor passes through critical regions. 

• Design iteration: If issues are found, we explore modifications such as adjusting shaft dimensions, changing support positions or adding damping. 

• Integration with other models: We link rotor dynamics with CFD and thermodynamic models, ensuring consistency across the full system. 

This structured approach enables us to combine speed with accuracy. We can quickly identify risks, but also drill down into detailed effects when needed. 

Benefits for Our Clients 

Reduced risk of failure 

By identifying potential vibration or resonance issues at an early stage, rotor dynamics analysis helps prevent costly downtime and damage to critical machinery. This proactive approach protects investments and ensures that equipment continues to operate safely. 

Improved reliability 

Machines designed with rotor dynamics in mind are less prone to wear and more consistent in their performance. This means smoother operation, fewer unexpected shutdowns and a longer service life. 

Lower development costs 

Carrying out analysis early in the design process reduces the need for redesigns, physical prototypes or trial-and-error fixes later. Clients benefit from shorter development cycles and greater cost efficiency. 

Confidence in performance 

When dynamic behaviour has been validated in advance, clients can proceed with procurement and operation knowing that potential risks have already been addressed. This assurance supports both technical and commercial decision-making. 

Transferable knowledge 

DOCAN can hand over models for in-house use, giving client teams the ability to continue assessments or extend the analysis in future projects. This turns rotor dynamics into not just a service, but a foundation for long-term capability. 

Taken together, these benefits mean that investments in machinery are better protected, projects move forward with greater certainty, and equipment continues to deliver value throughout its lifecycle. 

Real-World Applications 

Rotor dynamics is not simply a theoretical exercise; it has a direct impact on real projects across industries. In high-speed turbomachinery such as turbines and compressors, operating speeds can approach critical values. Our analyses ensure safe separation margins and stable operation, helping clients to achieve efficiency without compromising reliability. 

When equipment is being retrofitted or upgraded, rotor dynamics checks play an equally important role. We confirm whether the existing system can cope with the new conditions or whether modifications are required. This avoids unforeseen problems and supports smooth project execution. 

In drive train systems, where shafts, couplings, motors and gearboxes interact, both lateral and torsional dynamics must be assessed. By modelling these effects, we ensure the system remains stable and avoids harmful interactions between components. 

For machinery operating under variable regimes – such as frequent start-ups, shutdowns or load swings – we simulate transient behaviour. This allows us to understand how rotors pass through critical ranges and to define safe operating procedures. 

Finally, rotor dynamics is a valuable tool in troubleshooting and diagnostics. When vibration issues arise in the field, analysis helps to identify the root cause and guide corrective action, saving both time and resources. 

These applications show that rotor dynamics is far from a niche analysis. It is a practical and versatile tool that helps to solve real engineering challenges, delivering tangible value for our clients. 

Strengths and Considerations 

Working with SoftInWay’s rotor dynamics tools has given us a clear view of both their strengths and the factors to keep in mind. 

Strengths: 

• Integrated with turbomachinery and system modelling in one platform. 

• Fast iteration for design changes and optimisation. 

• Flexibility for non-standard configurations through custom modelling. 

• Extensive libraries of materials, bearings and templates. 

• Strong technical support through the DOCAN X SoftInWay partnership. 

Considerations: 

• Input data must be accurate – geometry, material properties and support stiffness all matter. 

• More detailed modelling can increase complexity and run times. 

• Results must be interpreted by experienced engineers to ensure correct conclusions. 

• Fluid-structure interaction effects may require careful coupling with CFD or FEA. 

• By being aware of these factors, DOCAN ensures that analyses are both accurate and meaningful. 

Looking Ahead: Driving Innovation with Rotor Dynamics 

Rotor dynamics continues to evolve as machinery becomes more advanced. At DOCAN, we see opportunities to integrate these analyses even more deeply into digital workflows. This includes linking rotor dynamics with optimisation routines, using digital twins for real-time monitoring, and expanding into coupled multiphysics simulations.  

By staying at the forefront of these developments and working closely with SoftInWay, we aim to provide our clients with even greater insight and assurance, helping them design machines that are safer, more reliable and more efficient. 

If you’re looking to improve the performance and reliability of your rotating equipment, DOCAN can help. Get in touch today to explore how our rotor dynamics expertise and SoftInWay partnership can support your next project.