Romax designer DT 2023.1 cracked release

This article contains some overview information about the new features in Romax DT.

An on-demand webinar is available below, where Dr. Michael Platten, Senior Product Manager – Romax, explains some of the highlights from the 2023.1 release of the Romax software suite.

Key Highlights of Romax DT 2023.1 include:

Modeling and Usability

• 2D Worksheet – support for bearings with 1D ring flexibility

The 2D Worksheet now shows which bearings have 1D raceway connections.

This allows users to quickly check all the bearings in a model to see which are configured to have 1D raceway flexibility and which do not.

(Note, a similar visual check if bearings have 3D (FE) raceway flexibility is enabled.)

• 2D Worksheet – planetary shaft modeling

The modeling of planetary gear sets has been overhauled in Romax 2023.1.

It is now exceedingly quick and simple to model epicyclic (planetary) gear trains in Romax, including multi-stage and compound sets.

This has been achieved with new features in the drag-and-drop 2D Worksheet and the Romax planetary components

The following components are now editable in the 2D Worksheet:

• Planetary shafts
• Planetary shaft carriers (a.k.a. carrier discs)
• Planetary gears

• Planetary shaft assemblies are proxied by default.
• Planetary shafts now support loading gears – enabling rough sizing of non-standard planetary arrangements
• Gear geometry is re-calculated automatically upon changing planetary shaft positions/geometry
• FE Planetary shafts are supported in the 2D Worksheet.

• 2D Worksheet – support for all load components

The Dynamic Unbalance Load, the Belt Load, and the Wheel Load can now be seen and edited in the 2D Worksheet. With this, all types of loading components can be modeled in the 2D Worksheet.

   

• 2D Worksheet – ‘Merge Shafts’ tool highlights the selected shaft section

The Merge Shafts/Sections tool now highlights the shaft section the user has selected for merging instead of highlighting the whole shaft.

2022.1

2023.1

• 2D Worksheet – improvements to display of FE shafts and housings

Modeling with FE shafts and FE housings in the 2D Worksheet has been improved in a number of ways:

1. FE housings are no longer displayed while the Define Aligned Section tool is activated.
   • This removes FE cross-section loading times while defining a custom user-defined section view for large models.
2. FE components now have a border around their outline for improved 2D visualization.
   • This makes it clearer to see FE components, especially if the FE has a custom color defined.
3. Mounting of components on locked FE components with free mounting nodes is now supported.
   • This makes it easier to add a new component onto an FE shaft when its node connections are locked (to avoid re-condensation).

 

2022.1

2023.1

• Creation and management of proxy assemblies

Users can now create ‘synchronized copies’ of an assembly that will inherit the same components and loading parameters.

Any changes to the original assembly will automatically be applied to these ‘proxy’ assemblies.
This makes modeling less repetitive, less error-prone, and much faster for Romax models that have multiple instances of the same assembly. Examples include planetary gearboxes, bolts, mounts, and more.

• Planetary carrier connection usability improvements

The detailed planetary shaft carrier interface, used to position and manage planetary shafts, has been vastly improved.

Detailed planetaries use a non-physical object called a planetary shaft carrier (or a carrier disc) to manage the connections between planetary shafts and non-planetary (carrier) shafts.

The new interface brings a series of new features:

• A grid-based positioning tool for planetary shafts
  • Values can be copy-and-pasted for easy data entry
  • Grid data can be copied in and out of Romax (e.g. to or from Excel)
• Multiple planetary shafts can be connected at one time
• 3D view has checkboxes to toggle various components on/off
• Planetary shafts connected to multiple carrier discs can switch which carrier they are positioned from
• A visual aid has been added to help with positioning planetary components

Additionally, converting a planetary gear set from a concept carrier to a detailed carrier has been improved to embed planetary modeling best practices.

• Two planetary shaft carriers are added on either side of the gear set
• Default tree structure of a detailed planetary assembly has been enhanced to simplify model management

Gears

• Cylindrical Gears – advanced LTCA (General Availability Release)

The Advanced tooth bending stiffness model for loaded tooth contact analysis (LTCA) was first released in the 2022.1 version and labeled as Beta. In this release, the model has transitioned from its Beta phase to General Availability, resulting in the removal of the Beta label and related warnings. This is the criteria we set and met in order to justify this:

• Completed ‘basic model’ internal tests, which serve as sanity checks for physical phenomena in gear contact which the Advanced model should be able to capture
• Collected feedback from users and where possible further validate the model. We have customer permission to share 2 of the validation studies we received – one against a physical test and one against a customer’s internal FEA-based code – and we have made various enhancements as a result of user feedback
• Made improvements and addressed important issues raised from Beta testing.

• Cylindrical Gears – lead slope error compensation in Dontyne form grinding

Due to manufacturing constraints, typically there are differences between the designed and manufactured tooth profile. The cylindrical gear grinding simulation functionality (powered by software from Dontyne Systems embedded in Romax software) allows designers to simulate the gear finishing process and therefore analyze the manufactured tooth profile. This gives increased confidence in achieving the intended design.

When the finishing process is profile/form grinding, the lead slope modifications are typically achieved through different movements of the tool, such as radial plunging of the grinding wheel towards and away from the workpiece. However, this radial movement results in unwanted micro-geometry modifications because the tool profile is shifted up and down with respect to the gear. This changes the involute slope or pressure angle slightly at different positions along the gear face width. This is sometimes observed as bias or twist of the flank profile.

It is possible to consider lead slope modifications as small changes to the gear helix angle. If the directions of the lead slope modifications of both flanks are such that they allow this, it is possible to apply the lead slope by adjusting the grinding tool path and profile such that it effectively cuts a gear with a slightly different helix angle. This eliminates some of the radial movement, and in turn, reduces the amount of unwanted micro-geometry modifications.

It is now possible to account for this approach when using the cylindrical gear grinding simulation in Romax Enduro, Romax Spectrum, and Romax Energy to form ground gears.

Bearings

• Journal Bearings – User-defined operating temperature

The operating temperature of the journal bearing lubricant film can now be directly specified. In previous versions, the journal bearing operating temperature was determined as the mean temperature of its shaft and housing. This can now be overridden with a custom value, for example, obtained outside of Romax software, and this temperature will affect the lubricant viscosity used in the journal bearing component calculations.

• Rolling Element Bearings – Multi-lobe ovalization and custom bearing ring distortion

Rolling bearings may be radially deformed by design from a circular shape to a bi-lobe, tri-lobe, or other geometry in order to limit skidding. Previously it was already possible to define ovalization (i.e. bi-lobe shape) in Romax software. Now, this has been extended to allow multiple lobes and custom shapes, primarily to enable the modeling of tri-lobe raceways, but more lobes or an entirely custom shape are also enabled. This allows parametric investigation of the applied raceway distortion and its impact on load and stress distribution and ring deformation.

Note: This feature was also released in 2022.1 Update 230106. There is no difference in the functionality compared to that Update

No lobes	Tri-lobe

 

 

• Rolling Element Bearings – 6 Degree-of-freedom cage dynamics

The previous Bearing Dynamics capability in Romax Spin has a simplified representation of cages. The cages are considered rigid and they were only allowed to rotate about their own axis. This development addresses one of these limitations by adding lateral and tilt degrees of freedom to the cages, in addition to the rotation about their own axis. This would allow engineers to analyze the lateral motion of a cage and its stability by looking at the whirl orbits under various operating conditions.

 

• Rolling Element Bearings – addition of NTN catalog

A new bearing catalog from NTN has been added to Romax software. It is available alongside existing bearing catalogs and offers matching functionality. The catalog data is based on the General Rolling Bearing Catalog issued separately by NTN. As with other bearing supplier catalogs, limited data has been provided by NTN and the rest of the bearing internal and advanced data has been estimated by Romax.

Electric Machines

• User-defined axial forces for static analysis

The axial force per stator node has been added as an input in the electric machine Force and Excitation Data dialog. This allows a static axial force to be applied to all stator nodes in a model, for example when simulating an electric machine with a skewed rotor.

• Excitation interface license change

All electric machine interfaces, previously licensed on PI-24, have been moved to base products.
Any user of a base product (Enduro, Spectrum, Spin, Energy) will be able to import electric machine geometry from Motor-CAD, Opera, and JMAG-Express, as well as being able to launch the JMAG-Express Online client.

Also, all users of eNVH analysis in Spectrum (ND-12) will be able to import electric machine excitations via the excitation interfaces (.json files from Motor-CAD, Opera, Ansys Maxwell, Manatee, or .csv files from JMAG).

Solvers

• Upgrade of FE solvers

The Finite Element (FE) tool suite within Romax has been updated to the latest available version.
Some key capabilities of the FE tool suite within Romax are:

• 3rd party FE file access (Nastran, OptiStruct, Ansys, Abaqus)
• Mesh generations
• Static and dynamic condensations
• Mode shape calculations
• Static analysis solutions and visualisations (deflections/stress/strain)

Romax Enduro 

• Cylindrical Gears -plastic gear strength rating according to VDI 2736

The standard VDI 2736-2:2014 has been implemented in Romax Enduro enabling the specification and analysis of thermoplastic gears. This development allows the user to:

• Define and store in a database plastic materials with properties that vary depending on temperature, moisture, and lubrication
• Run a gear rating analysis for the plastic gears and obtain results such as flank and root safety factors, stresses, intermediate factors, and average wear
• Run micro-geometry analysis and obtain 2 new plots – specific sliding and local linear wear
• Use a number of new targets and results in Parametric Study and Batch Running relevant to the VDI 2736 rating

This makes it possible to use Romax Enduro to help engineers to design, analyze and optimize plastic gears.

 

• Rolling Element Bearings – inclusion of EP additives in the ISO 281 and ISO/TS 16281 results report

The EP Additives setting is now reported alongside the lubricant name and level of contamination in the reports ISO 281 and ISO/TS 16281 Results to give the user more context when reviewing bearing life results. This feature minimizes the effort required to check the status of EP additives on individual bearings.

The report appears from the Reports tab toolbar: ‘Bearing Results’; Bearings > ‘ISO 281 and ISO/TS 16281 Results…’.

 

• Parametric study and batch running enhancements

Several enhancements to Parametric Study and Batch Running are included in the 2023.1 release.
These enhancements give more flexibility to what can be achieved in an automated way using Parametric Study and Batch Running.

• Support for legacy scuffing rating standard ISO/TR 13989

We have introduced options to use the now withdrawn standard ISO/TR 13989 for the calculation of scuffing load capacity of cylindrical gears. The main reason is that the GL and IEC guidelines for certification of wind turbines still quote this standard, so the ability to use the legacy standard enables compliance with the guidelines.

The following options are available in Analysis Settings > Ratings > Gears

• ISO/TS 6336-20:2017
• ISO/TR 13989-1:2000 (2021.1)
• ISO/TR 13989-1:2000

 

Romax Spectrum 

• Electric Machines – NVH excitation fixes and enhancements

We have fixed a few issues regarding how Romax applies Electric Machine excitations in NVH analysis.

Due to an error in how excitations were transformed between local and global coordinate systems, rotor excitations (torque ripple, and the reaction on the rotor to radial and axial stator excitations) were always applied to the electric machine rotor node relative to the global z-axis. This meant that the predicted vibration response was incorrect when the local z-axis of the electric machine was not aligned with the global z-axis.

A related issue also caused stator excitations to not be updated when rotating the electric machine component about any axis (for example by applying the Transform Gearbox tool). In general, these issues led to an overprediction of vibration amplitude at lower frequencies in affected models.

Fixes have been applied to ensure that any new excitation datasets are automatically created in the correct orientation and to ensure that coordinate transforms are appropriately applied. In addition, when loading a model that contains electric machine excitations, the user has the option to automatically check and correct excitation data.

Note: These fixes were also released in 2022.1 Update 230330 and 2022 Update 230411. There is no difference in the functionality compared to these Updates.

 

• Dynamic Substructure Export – MSC Nastran format

Dynamic substructure export can be used for exporting a Romax powertrain model for further analysis, visualization, optimization, and implementation within end-product assemblies (such as full vehicle structures). In 2023.1, we have added the option to export a Romax model in a format compatible for solving with MSC Nastran. The functionality of the MSC Nastran dialog is identical to the existing OptiStruct substructure export feature.

 

• Acoustic analysis update and Improvements

Acoustic Analysis has been improved to support better performance of large models at high frequencies. A number of changes have been made that together make significant differences by better balancing simulation time, memory requirements, and accuracy. The demand for higher frequency analysis – particularly for electric powertrains – leads to a higher density of elements in the acoustic volume mesh. In addition, there has also been an increase in the physical size of the models being analyzed which leads to an increase in the size of the acoustic volume mesh. In both cases this leads to an significant increase in degrees of freedom which needs more memory and more processing time to solve.

Tests on a selection of models (including some very large models) show that these changes typically reduce simulation time and memory usage by at least 50% and sometimes up to 90%. Additionally, accuracy of results improved when using the new default settings compared to the previous default settings.

 

Example model

• 827x506x371mm
• 730k (structural elements)
• 455k (structural nodes)
• 10~5000Hz
• Quadratic acoustic volume mesh

• Injection lubrication for calculation of mesh losses (General Availability Release)

Injection lubrication (also known as jet lubrication) is commonly used in gearboxes as an alternative to splash lubrication. E.g. in high-speed transmissions where churning losses from splash lubrication may be high, or in wind turbine gearboxes where speeds can be too slow to ensure adequate lubrication using only splash lubrication.

Equations to calculate the mesh loss due to injection lubrication have been implemented based on modified versions of equations presented in ISO 14179-2 (DE). These losses can be included within the Gear Rattle Analysis tool in Romax Spectrum.

• Parametric study and batch running enhancements

Several enhancements to Parametric Study and Batch Running are included in the 2023.1 release. In addition, one of the micro-geometry plots has been renamed to make it clearer. These enhancements give more flexibility to what can be achieved in an automated way using Parametric Study and Batch Running.

Romax Energy 

• Injection lubrication for calculation of mesh losses (General Availability Release)

Injection lubrication (also known as jet lubrication) is commonly used in gearboxes as an alternative to splash lubrication. E.g. in high-speed transmissions where churning losses from splash lubrication may be high, or in wind turbine gearboxes where speeds can be too slow to ensure adequate lubrication using only splash lubrication.

Equations to calculate the mesh loss due to injection lubrication have been implemented based on modified versions of equations presented in ISO 14179-2 (DE). The implementation incudes;

• Calculations for gear mesh loss due to injection lubrication for helical, bevel or hypoid gears that are mounted to shafts within a gearbox.
• Modifications to known errors in the ISO based on Romax experience. These modifications give results that are a closer match to literature results than using the standard equations.
• Calculations for determining the injection direction influenced by the mesh rotation sense.
• A visual representation of the injection direction in the 3D gearbox view.

These capabilities were released in Romax Energy 2022, and were originally available on a restricted module (RS-12). All functionality has now been moved to Romax Energy (ET-01) and Gear Rattle Analysis (ND-16), therefore all users of these modules will have access to this feature.

• No changes have been made to the calculations for 2023.1, however small workflow changes have been made.

 

Romax Spin 

 

• Rolling Element Bearings – inclusion of EP additives in the ISO 281 and ISO/TS 16281 results report

 

The EP Additives setting is now reported alongside the lubricant name and level of contamination in the reports ISO 281 and ISO/TS 16281 Results and Bearing Certification Report (ISO 281 and ISO/TS 16281) to give the user more context when reviewing bearing life results. This feature minimizes the effort required to check the status of EP additives on individual bearings.

The reporting appears from the Reports tab toolbar: ‘Bearing Results’; Bearings > ‘ISO 281 and ISO/TS 16281 Results…’; and Bearings > ‘Bearing Certification Report (ISO 281 and ISO/TS 16281)’.