Improved Powertrain Simulation Communications Within OptiStruct

Data input between OptiStruct and AVL EXCITE reduced by 50%.

OptiStruct and EXCITE users will be happy to see improved integration between the two CAE software tools. This close connection between the software tools will help to limit errors, improve analysis and reduce workflow.

EXCITE is a simulation environment used to study the acoustics and dynamics of powertrain systems. It can study rigid and flexible multi-body dynamics. In fact, EXCITE includes a lubricated contact for slide bearings and pistons. These features will help users to assess vibrations, strength, acoustics, wear, friction and dynamics of engines, powertrains, drivelines, and transmissions.

OptiStruct, on the other hand, is an FEA solver within the HyperWorks suite. Its analysis specializations include structural, NVH (Noise, Vibration and Harshness) and flexible body engine dynamics.

Currently, OptiStruct is able to produce EXCITE input data files (.exb) without using any intermediate files. This helps limit an error prone workflow that can zap productivity. In fact, the improvement has been seen to reduce data input times by as much as 50%. The model import will include stress and structural information streamlining simulation.

The EXCITE calculations of stresses from frequency and transient response analysis are faster and easier with OptiStruct. Over 3 GB of data can be generated in less than a minute thanks to EXCITE’s generation of modal participation coefficients. This data can also be saved to .op2 and .h3d for use in Hyperworks and third party software.

“Previously, engineers had to run the FEA and then manually convert the results data to be used in AVL EXCITE for the analysis and simulation of the complete transmission … The Altair OptiStruct-AVL EXCITE interface demonstrates the strength of the open architecture of the Altair HyperWorks suite, which can be customized to interact with other software tools to meet customer requirements for task automation. This flexibility enables a more integrated approach to the product design process, translating into significant time and cost savings for the customer,” said Harold Thomas, Development Director at Altair.

Altair reports that the automated export/import interface is becoming popular with OEM customers. However, the tool will also be useful to sectors like automotive, aerospace, off-road, rail and motorsports.

Mikhail Ejakov, Global Technical Specialist at Ford Motor Company said, “The use of Altair OptiStruct allows us to directly create the AVL EXCITE .exb input data file … This new capability eliminates the need to create and translate large intermediate files which can be very time consuming with large models, leading to significant improvements in turnaround time and robustness of the engine dynamics analyses with AVL EXCITE.”

Other improvements include:

  • Result subset outputs
  • Tied contact for dissimilar meshes

Source Altair. Image from AVL.

Written by

Shawn Wasserman

For over 10 years, Shawn Wasserman has informed, inspired and engaged the engineering community through online content. As a senior writer at WTWH media, he produces branded content to help engineers streamline their operations via new tools, technologies and software. While a senior editor at, Shawn wrote stories about CAE, simulation, PLM, CAD, IoT, AI and more. During his time as the blog manager at Ansys, Shawn produced content featuring stories, tips, tricks and interesting use cases for CAE technologies. Shawn holds a master’s degree in Bioengineering from the University of Guelph and an undergraduate degree in Chemical Engineering from the University of Waterloo.