Aurobay uses Simcenter 3D to reduce simulation time by 88 percent and streamline NVH performance analysis
Aurobay, which was part of Volvo Cars and Geely, develops and produces powertrain solutions for the global market. Aurobay is a pioneering supplier of propulsion technology, development services and contract manufacturing with operations in Europe and Asia. It produces premium hybrid engines that already power millions of vehicles.
It is clear electric motors are the future of road transportation but it’s not a case of simply stopping the production of internal combustion engines (ICEs) and immediately switching everything to electric. It’s a gradual transition that must be carefully managed by manufacturers. They need to satisfy the demand for ICEs while continuing to ramp up the production of electric motors to meet that market’s growing demand. And they need to remain competitive throughout.
Aurobay, formerly part of Volvo Cars Powertrain Engineering, specializes in the development of both internal combustion and hybrid engines. However, specializing in both presents significant financial and engineering challenges.
To counter this, Aurobay looks for software tools that can be used for both disciplines. This means purchases don’t need to be made twice, and engineers can switch between hybrid and internal combustion engine projects without having to learn how to use new tools. Using the same tools for both also allows Aurobay to invest in the best software that will enable the highest levels of optimization.
Following an extensive product review, Simcenter™ 3D software, part of the Siemens Xcelerator business platform of software, hardware and services, was identified as the solution that could perform at the same high level when handling ordered or speed data, making it an excellent choice for Aurobay.
One fundamental difference between predicting vibrations in ICEs and electric motors is the former requires more extensive analysis of speed data (also known as Waterfall of Frequency Spectra Analysis) whereas the latter requires a greater focus on analysis of ordered data, while both are used equally with hybrid engines. When evaluating solutions, Aurobay found that most specialized in one or the other. When they found Simcenter 3D could be used to do both equally well and switch between the two without further analysis, that cinched the deal.
Technical leader Hans Johannesson explains the ease of integration was also a significant factor in the decision: “Some solutions have a completely closed ecosystem,” he says. “So we’d have to switch everything over, which would take considerable time and investment. But we’re able to use Simcenter 3D alongside our other tools, which makes it much easier to use, faster to integrate into the full toolchain and more affordable to implement.”
To measure this, Aurobay engineers first calculate the structural dynamics vibrations caused by the engine. Excitation loads are then added, and acoustic radiation is predicted. Using their previous acoustic tool, 21 full finite element (FE) runs were needed for each scenario to get enough data to make accurate predictions. However, by using Simcenter 3D, only one FE-based reduced order model (ROM) needs to be created for each scenario. It captures the acoustic sensitivity of the vibrations and can be quickly and easily re-used for different operating conditions. “Using Simcenter 3D reduces the overall simulation time from over 2 hours to just 15 minutes, a significant time saving when applied over multiple scenarios,” says Johannesson.
By using Simcenter 3D for development, Aurobay benefits from a significant reduction in simulation time. Although more work is initially required to set the ROM using a full finite element analysis (FEA), unlike other solutions, with Simcenter 3D this only needs to be done once.
The ROM can then be handed over to less experienced engineers who can conduct extensive analysis by adjusting the parameters of the loading conditions and running various analyses using a linear solver.
This generates vast amounts of results data that would be impossible to use when performing manual analysis. However, the Simcenter 3D postprocessing tools make it easy to search and find the relevant information that aids development. In fact, at Aurobay this step is often performed by an analyst who prepares the data and shares it across all the teams within the organization. This means not only do all people receive crucial information faster, but engineers are also freed up to work on the next stage of the project or on another project entirely.
Having proven the success of incorporating Simcenter 3D, Johannesson is planning to add more Simcenter solutions to Aurobay’s processes in the future: “We focus on designing and building powertrains, but these are used in complete vehicles so it’s important to understand how they behave when installed. Therefore, we’re planning to make use of Siemens Digital Industries Software’s facilities and products that allow us to combine our simulations with
physical testing.”
Combining the two will allow Aurobay to conduct a more extensive evaluation of noise, vibration and harshness (NVH) performance, such as the noise inside the vehicle cabin to optimize end products for even greater comfort.
“We intend to use the Simcenter STAR-CCM+ CFD tool for input to Simcenter 3D Acoustics,” Johannesson continues. “This will enable us to analyze flow acoustics as well as vibration acoustics. Simcenter STAR-CCM+ can give us data on things such as pressure on a duct and then we can use Simcenter 3D to predict the noise this generates.”