Romax 2026.1: A New Foundation for Drivetrain Simulation

Every great leap forward starts with a stronger foundation. Romax 2026.1 is that foundation, a release built to carry drivetrain simulation into its next era. It's headlined by a preview of the reimagined Static Analysis (2nd Generation) engine, backed by smarter electric machine NVH workflows, major speed gains in condensation, and a host of usability improvements that make everyday work faster and more intuitive. Together, these updates set the stage for how you'll design, analyze, and innovate in the years ahead. Let's dive into what Romax 2026.1 brings.

1. Static Analysis (2nd Generation) – Preview

For more than 30 years, the Romax (1st Generation) Static Analysis solver has delivered the fast, reliable simulation capabilities trusted by drivetrain engineers worldwide. However, both simulation requirements and computing technology have evolved significantly over that time. Modern drivetrains are more complex, models are larger, and today's hardware offers far greater parallel processing and memory capacity than was available when the original architecture was developed.

To address these challenges, the Romax team has developed Static Analysis (2nd Generation), or simply "2nd Gen." Built from the ground up using decades of drivetrain simulation expertise, it introduces a modern solver architecture designed to support larger and more complex models, take advantage of modern computing hardware, and provide a foundation for future innovation across the Romax portfolio.

Static Analysis (2nd Generation) uses broadly similar ideas to 1st Gen and, to a user, appears to work similarly, yielding results that are almost identical or similar, aside from some deliberate changes. However, 2nd Gen incorporates some key innovations that bring several key benefits:

• Scalability and usability for large models and large numbers of load cases
• Improved runtimes for large duty cycles on multicore machines
• Improved convergence of models with many degrees of freedom
• Accelerated innovation and future-proof software

2. Frequency-Domain Import of Electric Machine Excitations

In many eDrive applications, electric machines are driven by inverters using pulse width modulation (PWM), which introduces additional harmonics into the winding currents and may appear in NVH test data as characteristic 'V-shaped' sidebands. Although PWM switching frequencies are often sufficiently high to push these outside the range of human hearing, high switching frequencies typically lead to higher inverter losses; therefore, it may be desirable to use a reduced switching frequency to improve system efficiency.

To help users evaluate the effect of PWM as part of their drivetrain NVH process, we have added an option for the user to directly import electric machine excitations in the frequency domain using a *.json file format. This import bypasses the built-in pre-processor, allowing greater customization of workflows.

3. Automated Ansys Maxwell Interface for eNVH Optimization

The Ansys Maxwell force automator allows Romax users to obtain NVH excitations directly from an Ansys Maxwell electromagnetic model file, without having to open and run the Ansys Maxwell software themselves. Model parameters in the Ansys Maxwell model can also be tweaked for design optimization and sensitivity studies.

4. Accelerated External Dynamic Condensation Using MSC Nastran

In Romax Spectrum, users can opt to use an external third-party solver to perform dynamic condensation of FE parts rather than using the built-in condensation solver. This is particularly useful for components with many elements and large numbers of condensation nodes - such as housings - where users may have access to solvers on HPC systems. This feature accelerates the end-to-end condensation process when users perform external condensation using MSC Nastran.

As an example, the time for an average-sized housing condensed over an average-sized frequency range saw a reduction in end-to-end processing time from 5,778 seconds to 1,498 seconds, or a 74% reduction.

5. Improvements to the Analysis Settings Dialog

The usability of the analysis settings dialog has been improved by renaming and rearranging tabs and settings. The dialog should be more intuitive, and settings should be easier to find, especially the important ones.

6. Definition of Load Case Dependent Temperatures for Summary Result Duty Cycles

Load case-dependent component temperature support has been added for load cases inside a summary result duty cycle (SRDC). When using a model with SRDCs and selecting an SRDC to investigate, you can now define component temperatures using the existing temperature spreadsheet.

7. Roller Bearing Contact Stress Export in Parametric Study and Batch Running

The action 'output raceway stress results' available in parametric study and batch running now outputs the raw data in text files in addition to the contact stress plots previously output as images.

8. HTML Report Generation in Parametric Study and Batch Running

There is a new action in parametric study and batch running called 'generate reports' available for each duty cycle, including both full results and summary results duty cycles.
This action can be used to generate some of the most commonly used standard reports available from the reports tab. The specific report and the output directory can be specified in arguments for actions.

9. Reporting of Highest Loaded Ball/Roller Results in Parametric Study and Batch Running

The values of load and angle of the ball or roller with the highest raceway load have been added as targets/results in parametric study and batch running. For double-row bearings, these are available for each row individually. This makes it possible to include these parameters as targets in studies and as results in automated workflows using batch running.

10. Gear Scuffing Temperature Enhancements and Availability in Parametric Study and Batch Running

The parameter previously called operating temperature, found in gear rating analysis settings and used for scuffing calculations, has been modified and is now available as a variable in parametric study and batch running.

11. Improved Checks for Multiple Materials When Importing FE

An additional check has been added during FE component import to detect multiple materials. If multiple materials are detected, a warning will be displayed prompting the user to check that the material assigned to bearing connections is correct after import. Bearings will default to the first material ID, which may be incorrect.

This check reduces potential user modeling errors in bearings caused by an incorrect material definition for the FE component to which they are connected.

12. Support for Lead Mismatch in Customized Reporting

The result lead mismatch, which is a type of gear mesh misalignment, has been added to customized reporting and to two templates - gear mesh misalignment summary and gear mesh misalignment detailed. This makes the gear mesh misalignment results in customized reporting more complete and consistent with the same available in standard reports.

This is just the beginning. Romax 2026.1 lays a foundation built for the future, one that grows stronger with every model you run on it. Don't forget to share your feedback with us.

For more details, refer to this SimCompanion article, or contact us for more information on the Romax 2026.1 software suite.