Tunable acoustic absorber with micro deep hole array

Yoda, Mitsuhiro; Saito, Susumu; Akishita, Sadao; Konishi, Satoshi

doi:10.1109/mhs.1998.745778

Cited by 3 publications

(5 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…22,25 A screw adjustment 25 of the cavity volume provides a simple mechanical means to tune the resonant frequency of a Helmholtz resonator. Similarly, a stepper motor 26,27 was previously used to change the back cavity volume of the MPP absorber, moving the back cavity plate from 6 mm to 12 mm. These cavity tuning methods are however impractical and costly for large-area MPP.…”

mentioning

confidence: 99%

“…Such a membrane tuning method does not require discrete mechanical parts as for the reported cavity tuning method. [25][26][27] This MPDEA has a circular dielectric elastomer (DE) membrane which is radially pre-stretched and has its outer edge fixed to a rigid cylindrical tube of radius R 0 . The membrane was laser drilled with an orthogonal array of holes at a Author to whom correspondence should be addressed.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Electrically tunable and broader-band sound absorption by using micro-perforated dielectric elastomer actuator

Lu¹,

Shrestha²,

Lau³

2017

Applied Physics Letters

View full text Add to dashboard Cite

Most membrane-type acoustic absorbers for low-frequency sound attenuation are applicable only at a fixed resonant frequency for a narrow bandwidth. Tuning of the acoustic absorption spectrum is desired to match the varying noises. This letter presents a micro-perforated dielectric elastomer actuator (MPDEA) to make a broader-band acoustic absorber electrically tunable. Voltage activation of the MPDEA reduces the membrane tension and hole size and thus enables the active shifting of the acoustic absorption spectrum. Such a membrane tuning method does not require discrete mechanical parts as for the cavity tuning method. Also presented are the analytical models to predict the voltage-induced hole size change and acoustic characteristics of MPDEA.

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

Electrically tunable and broader-band sound absorption by using micro-perforated dielectric elastomer actuator

Lu¹,

Shrestha²,

Lau³

2017

Applied Physics Letters

View full text Add to dashboard Cite

show abstract

“…Its resonant frequency depends on the hole sizes (i.e., diameter and depth) and the back-cavity volume 31,35,36 . Studies have used screw adjustment 35 or a stepper motor 37,38 to change the back-cavity volume of the MPP absorber. These cavity tuning methods are however impractical and costly for large-area MPP.…”

mentioning

confidence: 99%

A tunable acoustic absorber using reconfigurable dielectric elastomer actuated petals

Shrestha,

Lau,

Chin

et al. 2024

Commun Eng

View full text Add to dashboard Cite

Dielectric elastomer actuator (DEA)-based unimorphs that actively bend in one direction, can mimic the blooming motion of flower petals. Here we explore an application of such reconfigurable DEA to create tunable acoustic absorber capable of adapting to fluctuations in dominant noise frequency. The DEA-unimorphs consist of alternate layers of dielectric elastomers and compliant electrodes bonded to a Mylar sheet and were micro-slotted to form triangular petal-like structures that bend upon voltage activation. When arranged in an array, the micro-slotted dielectric elastomer bending actuators (MSDEBA) can open like flower petals, actively reconfiguring their open-ratio. Integrated with a base resonator comprising a micro-slotted panel (MSP) and a parallelly arranged varying-depth (VD) back-cavity, the MSDEBA forms a tunable acoustic absorber effective in the low-mid acoustic frequency range at inactive state. Meanwhile, upon voltage activation, it increased the absorber’s open-ratio and tuned the absorber to target a higher frequency. A 5 kV activation reconfigured the MSDEBA to shift its transmission loss peak by 72.74% (i.e., from 697 Hz to 1204 Hz). This acoustic spectrum tuning capability doubled the 15 dB absorption bandwidth of these absorbers from a bandwidth of ~435 Hz to 820 Hz. Such absorbers have the potential to tune the absorption spectrum to match the noise frequency in real-time to ensure optimal acoustic attenuation.

show abstract

“…Similarly, a stepper motor [175,221] was previously used to change the back-cavity volume of the MPP absorber, moving the back-cavity plate from 6mm to 12mm. These cavity tuning methods are however impractical and costly for large-area MPP.…”

Section: Introductionmentioning

confidence: 99%

“…This is achieved by voltage activation that reduces the membrane tension and thus hole size. Such a membrane tuning method does not require discrete mechanical parts as for the reported cavity tuning method [158,175,221].…”

Section: Introductionmentioning

confidence: 99%

Smart window for tuning transparency and noise absorption

Shrestha¹

View full text Add to dashboard Cite

Tunable acoustic absorber with micro deep hole array

Cited by 3 publications

References 3 publications

Electrically tunable and broader-band sound absorption by using micro-perforated dielectric elastomer actuator

Electrically tunable and broader-band sound absorption by using micro-perforated dielectric elastomer actuator

A tunable acoustic absorber using reconfigurable dielectric elastomer actuated petals

Smart window for tuning transparency and noise absorption

Contact Info

Product

Resources

About