In-wheel Helmholtz chambers

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roon
roon
412
Joined: Sat Dec 17, 2016 6:04 pm

In-wheel Helmholtz chambers

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http://world.honda.com/tech/auto/noise-reducing-wheel/

10dB reduction for driver at 220Hz.

bill shoe
bill shoe
151
Joined: Wed Nov 19, 2008 7:18 am
Location: Dallas, Texas, USA

Re: In-wheel Helmholtz chambers

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Nice! Cavity resonance is an air-borne noise within the tire that's so strong (jackhammer level) it drives structure-borne vibration into the rest of the car! This cavity resonance can be greatly reduced by determining wheel/tire sizes up front (which pretty much locks in the resonance frequency) and then designing wheel/suspension/subframe/body responses to be very quiet at those frequencies. The most important single thing is to not let the wheel rim have a mode at the cavity resonance frequency! But this sometimes occurs, or at least it used to. In practice it can be very difficult to predict all the wheel/tire combos that will ever be used over the life of a platform, so an add-on resonator would be a very nice tuning tool to have. In theory, they could be sold aftermarket in addition to thru an OE manufacturer.

Cold Fussion
Cold Fussion
93
Joined: Sun Dec 19, 2010 3:51 am

Re: In-wheel Helmholtz chambers

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Can the resonator be retrofitted to wheels or does it need to be considered at the wheel design stage?

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Holm86
232
Joined: Wed Feb 10, 2010 2:37 am
Location: Copenhagen, Denmark

Re: In-wheel Helmholtz chambers

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Michelin is using foam on the tire itself, to soak up the vibrations creating the noise

https://www.michelinman.com/US/en/why-m ... ology.html