Electronic Journal Technical Acoustics ISSN 1819-2408

J. A. Kim

Calculated and experimental method for determination of acoustical impedances of pipe systems elastic elements

language: Russian

received 24.01.2006, published 11.02.2006

Download article (PDF, 160 kb, ZIP), use browser command "Save Target As..."
To read this document you need Adobe Acrobat © Reader software, which is simple to use and available at no cost. Use version 4.0 or higher. You can download software from Adobe site (http://www.adobe.com/).

ABSTRACT

In engineering practice the means of noise control for liquid path of hydraulic and air pipelines (flexible insertions, hoses, bellows and etc.) are characterized by acoustic impedance. By definition it is the relation of sound pressure at the input and output of the element to the velocity at the input when velocity at the output is equal to 0. These parameters are sufficient for the description of transfer properties of an actual elastic element and are necessary for calculation. It is impossible as a rule to calculate these parameters. For the most part they are determined experimentally.
Calculated and experimental method, which allows to simplify procedure of acoustic impedance determination and to use experimental results in analysis, is considered. The elastic element is represented as a cascade connection of quadrupoles, which are equivalent to elastic and rigid parts of elastic element. The elastic part parameters (sound speed and loss factor) are determined from extremum of the absolute value of relation of sound pressure to velocity at the measuring chamber input. The other parameters are calculated.

5 pages, 3 figures

Сitation: J. A. Kim. Calculated and experimental method for determination of acoustical impedances of pipe systems elastic elements. Electronic Journal “Technical Acoustics”, http://www.ejta.org, 2001, 2.

REFERENCES

1. R. Singh, M. Schary. Acoustic impedance measurement using sine sweep excitation and known volume velocity technique. J. Acoustic Soc. Am. 64 (4). 995-1003. 1978.
2. Попков В. И., Попков С. В. Метод измерения акустических сопротивлений элементов систем трубопроводов. Техническая акустика. Т. V. Вып. 1-2. 1999.
3. Горин С. В., Ким Я. А., Лесняк А. Н., Селезский А. И. О способе экспериментального определения параметров передачи колебаний по жидкостному тракту элементов гидравлических систем. Акустический журнал. Т. XXXII. Вып. 4. 1986.
4. Ким Я. А. Об экспериментальном определении параметров передачи элементов и обору-дования гидро- и пневмосистем при протекании через них рабочей среды. Труды ЦАГИ им. Н. Е. Жуковского: Структурная акустика. Вып. 2479. 1990.
5. Справочник по технической акустике: Пер. с нем. Под ред. М. Хекла и Х. А. Мюллера.- Л.: Судостроение, 1980. 440 с.

JAKOV A. KIM principal researcher at Krylov Shipbuilding Research Institute (St. Petersburg, Russia), PhD. Expert in vibroacoustics of hydraulic systems