| Zugriffsnummer | 35930 |
| Dokumenttyp | Konferenzartikel |
| Sprache | Deutsch |
| Titel | A new scanning apparatus for the dissemination of the unit Watt in airborne sound. |
| Autor(in); Institution |
Brezas, Spyros; 1.7, Akustik und Dynamik, PTB-Braunschweig
Bethke, Christian; 1.7, Akustik und Dynamik, PTB-Braunschweig
Wittstock, Volker; 1.7, Akustik und Dynamik, PTB-Braunschweig
|
| Quelle/Jahr | Fortschritte der Akustik : DAGA 2016, Aachen, 42. Jahrestagung für Akustik:(2016), 1270 - 1273 |
| Availability | [DVD-ROM] ; file name: 000137.pdf |
| Herausgeber(in) |
Vorländer, Michael
|
| ISBN | 978-3-939296-10-2 |
| Verlag | Berlin: Deutsche Gesellschaft für Akustik, DEGA |
| Konferenzangaben | 42. Deutsche Jahrestagung für Akustik, Aachen, 14-17, März, 2016, Deutschland |
| Freie Schlagworte | Sound power ; scanning apparatus ; directivity ; arc |
| Zusammenfassung | The sound power emitted by a sound source can be determined in a hemifree field by averaging the sound pressure over an enveloping surface. At PTB, such measurements are usually performed by applying the spiral path method. The disadvantage of this method is that the sound source is rotated during measurements and that the microphone path physically covers only one quarter-circle. Within the EMRP-project "SoundPWR", a new scanning apparatus has been developed, set up and tested at PTB. lt will be used to disseminate the unit from the primary sound power standard to the transfer standards. The scanning apparatus consists of a hemi-circular arc that can be tilted over a hemispherical surface. Twenty four microphones can be mounted across the arc in a way that allows measurements over surfaces of different radii. An additional advantage of the new device is that the directivity of the sound source under measurement can be directly calculated. Major performance criteria like background noise and uniformity of the movement were optimised. This new device has been used to determine sound powers of aerodynamic reference sound sources. The results are compared to those derived by using a spiral microphone path. |
