Undirectional JMC actuators in the active attenuation of noise in ducts

Seppo Uosukainen, Vesa Välimäki

Research output: Contribution to journalArticleScientificpeer-review

Abstract

In feedforward active noise control systems in ducts, a natural solution to avoid the acoustic feedback from the cancelling actuator to the reference detector is to use a underectional actuato. New realizable ideal undirectional three- and two-element source configurations, based on the JMC method, are introducted. In the two-element actuator the elements act as a dipole with the monopole effect included in the same elements. The inter-channel delay in the control structure of the two-element actuator is optimized with three different ways. In one of them the delay element is omitted altogether. The output volume velocities of all the three variations of two-element Ideal Source are mutually identical and independent of the inter-channel delay opitmization, and also identical with those of Swinbanks' two-element actuator, although the procedure of attaining them is quite different. It turns ou to be advantageous in the practical implementation of digital control systems that the new three- and two-element solutions can be realized with no interchannel delays. Thus, it is possible to achieve simplified control algorithms and reduce the computing time or improve the performance.
Original languageEnglish
Pages (from-to)63-77
Number of pages15
JournalActa Acustica United with Acustica
Volume85
Publication statusPublished - 1999
MoE publication typeA1 Journal article-refereed

Fingerprint

ducts
actuators
attenuation
monopoles
dipoles
acoustics
Attenuation
output
detectors
configurations

Cite this

Uosukainen, Seppo ; Välimäki, Vesa. / Undirectional JMC actuators in the active attenuation of noise in ducts. In: Acta Acustica United with Acustica. 1999 ; Vol. 85. pp. 63-77.
@article{b57b1028309a45159398bc1484a606e9,
title = "Undirectional JMC actuators in the active attenuation of noise in ducts",
abstract = "In feedforward active noise control systems in ducts, a natural solution to avoid the acoustic feedback from the cancelling actuator to the reference detector is to use a underectional actuato. New realizable ideal undirectional three- and two-element source configurations, based on the JMC method, are introducted. In the two-element actuator the elements act as a dipole with the monopole effect included in the same elements. The inter-channel delay in the control structure of the two-element actuator is optimized with three different ways. In one of them the delay element is omitted altogether. The output volume velocities of all the three variations of two-element Ideal Source are mutually identical and independent of the inter-channel delay opitmization, and also identical with those of Swinbanks' two-element actuator, although the procedure of attaining them is quite different. It turns ou to be advantageous in the practical implementation of digital control systems that the new three- and two-element solutions can be realized with no interchannel delays. Thus, it is possible to achieve simplified control algorithms and reduce the computing time or improve the performance.",
author = "Seppo Uosukainen and Vesa V{\"a}lim{\"a}ki",
year = "1999",
language = "English",
volume = "85",
pages = "63--77",
journal = "Acustica United with Acta Acustica",
issn = "1610-1928",
publisher = "S. Hirzel Verlag",

}

Undirectional JMC actuators in the active attenuation of noise in ducts. / Uosukainen, Seppo; Välimäki, Vesa.

In: Acta Acustica United with Acustica, Vol. 85, 1999, p. 63-77.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Undirectional JMC actuators in the active attenuation of noise in ducts

AU - Uosukainen, Seppo

AU - Välimäki, Vesa

PY - 1999

Y1 - 1999

N2 - In feedforward active noise control systems in ducts, a natural solution to avoid the acoustic feedback from the cancelling actuator to the reference detector is to use a underectional actuato. New realizable ideal undirectional three- and two-element source configurations, based on the JMC method, are introducted. In the two-element actuator the elements act as a dipole with the monopole effect included in the same elements. The inter-channel delay in the control structure of the two-element actuator is optimized with three different ways. In one of them the delay element is omitted altogether. The output volume velocities of all the three variations of two-element Ideal Source are mutually identical and independent of the inter-channel delay opitmization, and also identical with those of Swinbanks' two-element actuator, although the procedure of attaining them is quite different. It turns ou to be advantageous in the practical implementation of digital control systems that the new three- and two-element solutions can be realized with no interchannel delays. Thus, it is possible to achieve simplified control algorithms and reduce the computing time or improve the performance.

AB - In feedforward active noise control systems in ducts, a natural solution to avoid the acoustic feedback from the cancelling actuator to the reference detector is to use a underectional actuato. New realizable ideal undirectional three- and two-element source configurations, based on the JMC method, are introducted. In the two-element actuator the elements act as a dipole with the monopole effect included in the same elements. The inter-channel delay in the control structure of the two-element actuator is optimized with three different ways. In one of them the delay element is omitted altogether. The output volume velocities of all the three variations of two-element Ideal Source are mutually identical and independent of the inter-channel delay opitmization, and also identical with those of Swinbanks' two-element actuator, although the procedure of attaining them is quite different. It turns ou to be advantageous in the practical implementation of digital control systems that the new three- and two-element solutions can be realized with no interchannel delays. Thus, it is possible to achieve simplified control algorithms and reduce the computing time or improve the performance.

M3 - Article

VL - 85

SP - 63

EP - 77

JO - Acustica United with Acta Acustica

JF - Acustica United with Acta Acustica

SN - 1610-1928

ER -