More than Plots and Graphs – Experience NVH First-Hand

Altair Partner Alliance (APA) member, Brüel & Kjær (B&K), is taking NVH testing and evaluation to the next level with their industry leading NVH Simulator. Dave Bogema, Product Manager – NVH Refinement at B&K, presented “The Benefits of Experiencing NVH & CAE Data from Pre-concept to Production” to a captivated audience at the Americas ATC East in Detroit, MI in October 2017. Conference attendees also got to experience the NVH Simulator first hand and take it for a test drive.

There are many factors driving change in Automotive NVH; increased fuel economy, lightweight designs, electric vehicles, autonomous vehicles, shorter lead times and more. In order to meet consumers’ expectations, NVH engineers are turning to simulation and eliminating the need for several physical prototypes.

Many types of CAE results and data can be understood visually, by observing them on a computer monitor. Decisions can be made instantly upon viewing and understanding the results. NVH data, especially sound and vibration that will be experienced by the user, is not like this. Generally, NVH data is in the form of plots, graphs, and numbers, which cannot be easily understood to the fullest extent by looking at them on a screen; they must be experienced as sound and vibration to fully understand them. Dave explains, “If we can accurately simulate the vibration and the sound of those vehicles and then turn that into something that we can experience as people in an experiential way, feel the vibration, hear the sound as we would in the real car; then we can design that vehicle to be exactly what we want long before we actually start making parts.”

In his presentation, Dave proposed that these challenges are best addressed by leveraging the latest generation of CAE and Test tools in a collaborative manner. Using a workflow that combines full vehicle NVH CAE simulation including Altair’s NVH Director with experiencing data from Test and CAE using the B&K NVH Simulator and follow up with benchmarking and validation. B&K has several products, including Insight+, which can take data that is generated from either test data, CAE data, or both and put it together to listen to it and understand what it’s actually going to sound like. By taking it further and putting that data into a virtual vehicle and adding vibration, users gain an understanding of how the vehicle will feel as well as sound when accelerating, braking, and changing gears. Dave explained the power of adding vibration, “a lot of the challenges in the NVH area right now are lower frequency in nature so when you get into that lower frequency type phenomena you really have to understand both vibration and sound together because as humans, we experience both at the same time and we interpret both at the same time and if you only have one or the other then you don’t really fully understand the implication of that.”

Experiencing NVH helps engineers gain a deeper understanding of their work and makes it easier for them to communicate with management and other teams working on a vehicle to make judgements on which powertrain to use or exhaust system or whether a vehicle needs more sound deadening. “Looking at a plot or a graph it’s very hard to justify one way or the other but if you can actually sit down and listen to the difference that makes it so much easier to make that decision… it reduced time to market in many different ways because that decision process is kind of short-circuited because you don’t have the unkown-ness of Is that the right decision?, Is it not?, let’s do some more testing.”

Learn more about Altair’s NVH software 
APA enabled HyperWorks users can download Insight+ by B&K

Check out our interview with Dave below:

 

Anyone Up for Badminton?

Is it possible to study and optimize the performance of a badminton racquet through simulation? Is it art or science to design a racquet?

 

Would it be possible to reuse knowledge from other simulation disciplines and apply them on sports equipment? Tools at hand were HyperWorks, a caliper, and my newly bought badminton racquet! The racquet was modeled using HyperMesh®, solved in RADIOSS®, and rendered in Evolve®.

See more of Magnus Lindvall’s fun simulations on the blog:

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