Uncertainty estimation in multi-port measurements
2015 (English)Conference paper (Refereed)
The generation and scattering behaviour of fluid machines in connected duct or pipe systems isof great interest to minimize disturbing and harmful sound emission, for instance of air condition systems. Within the framework of the European project ’IdealVent’ the acoustic behaviour of airconditioner systems in aircraft is investigated in detail in order to develop strategies to abate sound emission and hence augmenting safety and comfort within the airplane and at the aircraft ramp. One approach to handle such systems is to apply a linear multi-port model that includes direction-depending transmission and reflection coefficients for the propagating wave modes. Those parameters may be ascertained either numerically or experimentally. Once this characteristic data are determined for all elements of interest, the sound scattering and emission behaviour of every considerable com-bination of those elements can be calculated. In order to terminate the system scattering, a numberof external sound fields dominating the existing sound field are applied. This operation consists ofmatrix inversions and wave-number assumptions, which amplify uncertainties induced by the mea-surement procedure. The paper in hand shows a method to estimate the uncertainties for a multi-port of the order 6 by applying a condition number approach and a Monte-Carlo simulation.
Place, publisher, year, edition, pages
Research subject Vehicle and Maritime Engineering
IdentifiersURN: urn:nbn:se:kth:diva-160883OAI: oai:DiVA.org:kth-160883DiVA: diva2:791819
EuroNoise2015, the 10th European Congress and Exposition on Noise Control Engineering,Maastricht, Holland, May 31 - June 3
QP 201503032015-03-022015-03-022015-03-03Bibliographically approved