Automotive Engineering - June 2023 - 20

ENGINEERING AT THE
NEW NVH
FRONTIER
NVH testing at FEV's Auburn
Hills, Michigan, tech center
using HEAD Acoustics
instruments. With two parallel
analog-to-digital converters
the HEAD units cover the full
audible dynamic range.
Electrification brings new benchmarks, tools, and challenges to the ongoing
battle with noise, vibration and harshness.
by Lindsay Brooke
T
he complex science of analyzing and abating noise, vibration,
and harshness has entered a " new frontier " as the industry
transitions to electrified vehicles, experts in the NVH field tell
SAE Media. New design and engineering challenges at the
component, system, and full-vehicle levels continue to emerge as EV
offerings expand beyond the initial wave of predominantly premiumspec
products. Engineers note that benchmarking activity and the
introduction of new analysis and testing tools related to NVH mitigation
are at " crazy " levels.
" Our interest in acoustically improved vehicles always is going to
accelerate and the NVH technology must always meet customer
expectations, " observed Pranab Saha, whose company Kolana &
Saha Engineers in Waterford, Mich., specializes in acoustics, noise
and vibration analysis and testing. He noted that some of the latest
EV designs show progress in attacking both NVH sources and their
propagation paths. There is less reliance on " patch " materials -
urethane foams deployed in body cavities and mastics baked into
underbody areas that add mass, cost and complexity. But Saha and
other experts do not believe those so-called " Band-Aid " sound
dampers will be eliminated entirely.
" Occupants should not hear anything going on underneath them
20 June 2023
in the battery pack and electric drive system, while
outside the vehicle noise remains, " Saha asserted. " At
some point, those noises are going to become a quality
issue. "
Customer expectations of refinement in EVs versus
the incumbent IC-engine vehicles are still evolving. In
ICE vehicles, about 50% of NVH issues are related to
the powertrain. The other half are generated mainly by
road and wind noise. In EVs, the noise sources are
more balanced; the electric drive unit (EDU) noise is
important but road noise at low- to mid- speeds and
wind noise at high speeds " tend to dominate, " explained
Kiran Govindswamy, senior VP - Drivetrain,
e-Mobility and Vehicle, at FEV.
" One way to look at this is, noise coming from the
traction motor or geartrain is only important if the
customer hears it in the vehicle, " he said. " Sufficient
road and wind noise can, to an extent, mask the noise
coming from the EDU. This might be beneficial, but
you don't want it [road and wind noise] to be so bad
that the customer feels it's not a refined vehicle at all. "
AUTOMOTIVE ENGINEERING
FEV

Automotive Engineering - June 2023

Table of Contents for the Digital Edition of Automotive Engineering - June 2023

Automotive Engineering - June 2023 - INTRO1
Automotive Engineering - June 2023 - SPONSOR1
Automotive Engineering - June 2023 - CVRA
Automotive Engineering - June 2023 - CVRB
Automotive Engineering - June 2023 - CVR1
Automotive Engineering - June 2023 - CVR2
Automotive Engineering - June 2023 - 1
Automotive Engineering - June 2023 - 2
Automotive Engineering - June 2023 - 3
Automotive Engineering - June 2023 - 4
Automotive Engineering - June 2023 - 5
Automotive Engineering - June 2023 - 6
Automotive Engineering - June 2023 - 7
Automotive Engineering - June 2023 - 8
Automotive Engineering - June 2023 - 9
Automotive Engineering - June 2023 - 10
Automotive Engineering - June 2023 - 11
Automotive Engineering - June 2023 - 12
Automotive Engineering - June 2023 - 13
Automotive Engineering - June 2023 - 14
Automotive Engineering - June 2023 - 15
Automotive Engineering - June 2023 - 16
Automotive Engineering - June 2023 - 17
Automotive Engineering - June 2023 - 18
Automotive Engineering - June 2023 - 19
Automotive Engineering - June 2023 - 20
Automotive Engineering - June 2023 - 21
Automotive Engineering - June 2023 - 22
Automotive Engineering - June 2023 - 23
Automotive Engineering - June 2023 - 24
Automotive Engineering - June 2023 - 25
Automotive Engineering - June 2023 - 26
Automotive Engineering - June 2023 - 27
Automotive Engineering - June 2023 - 28
Automotive Engineering - June 2023 - 29
Automotive Engineering - June 2023 - 30
Automotive Engineering - June 2023 - 31
Automotive Engineering - June 2023 - 32
Automotive Engineering - June 2023 - 33
Automotive Engineering - June 2023 - 34
Automotive Engineering - June 2023 - CVR3
Automotive Engineering - June 2023 - CVR4
https://www.nxtbook.com/smg/sae/24AE09B
https://www.nxtbook.com/smg/sae/24AE09
https://www.nxtbook.com/smg/sae/24AE08
https://www.nxtbook.com/smg/sae/24AE06
https://www.nxtbook.com/smg/sae/24AE05
https://www.nxtbook.com/smg/sae/24AE04
https://www.nxtbook.com/smg/sae/24AE03
https://www.nxtbook.com/smg/sae/24AE02
https://www.nxtbook.com/smg/sae/23AE12
https://www.nxtbook.com/smg/sae/23AAVE11
https://www.nxtbook.com/smg/sae/23AE10
https://www.nxtbook.com/smg/sae/23AE09
https://www.nxtbook.com/smg/sae/23AE08
https://www.nxtbook.com/smg/sae/23AAVE07
https://www.nxtbook.com/smg/sae/23AE06
https://www.nxtbook.com/smg/sae/23AE05
https://www.nxtbook.com/smg/sae/23AAVE04
https://www.nxtbook.com/smg/sae/23AE04
https://www.nxtbook.com/smg/sae/23AE03
https://www.nxtbook.com/smg/sae/23AE02
https://www.nxtbook.com/smg/sae/23AAVE01
https://www.nxtbook.com/smg/sae/22AE12
https://www.nxtbook.com/smg/sae/22AVE11
https://www.nxtbook.com/smg/sae/22AE10
https://www.nxtbook.com/smg/sae/22AE09
https://www.nxtbook.com/smg/sae/22AE08
https://www.nxtbook.com/smg/sae/22AVE07
https://www.nxtbook.com/smg/sae/22AE06
https://www.nxtbook.com/smg/sae/22AE05
https://www.nxtbook.com/smg/sae/22AVE04
https://www.nxtbook.com/smg/sae/22AE04
https://www.nxtbook.com/smg/sae/22AE03
https://www.nxtbook.com/smg/sae/22AE02
https://www.nxtbook.com/smg/sae/22AVE01
https://www.nxtbook.com/smg/sae/21AE12
https://www.nxtbook.com/smg/sae/21AVE11
https://www.nxtbook.com/smg/sae/21AE10
https://www.nxtbook.com/smg/sae/21AVE09
https://www.nxtbook.com/smg/sae/21AE09
https://www.nxtbook.com/smg/sae/21AE08
https://www.nxtbook.com/smg/sae/21AVE07
https://www.nxtbook.com/smg/sae/21AE06
https://www.nxtbook.com/smg/sae/21AE05
https://www.nxtbook.com/smg/sae/21AVE05
https://www.nxtbook.com/smg/sae/21AE04
https://www.nxtbook.com/smg/sae/21AE03
https://www.nxtbook.com/smg/sae/21AVE03
https://www.nxtbook.com/smg/sae/21AE02
https://www.nxtbookmedia.com